Aluminium alloy
Encyclopedia
Aluminium alloys are alloys in which aluminium
(Al) is the predominant metal. The typical alloying elements are copper
, magnesium
, manganese
, silicon
and zinc
. There are two principal classifications, namely casting
alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable
and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost effective products due to the low melting point, although they generally have lower tensile strength
s than wrought alloys. The most important cast aluminium alloy system is Al-Si, where the high levels of silicon (4.0% to 13%) contribute to give good casting characteristics. Aluminium alloys are widely used in engineering structures and components where light weight or corrosion resistance is required.
Alloys composed mostly of the two lightweight metals aluminium and magnesium have been very important in aerospace manufacturing since somewhat before 1940. Aluminium-magnesium alloys are both lighter than other aluminium alloys and much less flammable than alloys that contain a very high percentage of magnesium.
Aluminium alloy surfaces will keep their apparent shine in a dry environment due to the formation of a clear, protective layer of aluminium oxide
. In a wet environment, galvanic corrosion can occur when an aluminium alloy is placed in electrical contact with other metals with more negative corrosion potentials than aluminium.
Aluminium alloy compositions are registered with The Aluminum Association
. Many organizations publish more specific standards for the manufacture of aluminium alloy, including the Society of Automotive Engineers standards organization, specifically its aerospace standards subgroups, and ASTM International
.
) or by names indicating their main alloying constituents (DIN
and ISO). Selecting the right alloy for a given application entails considerations of its tensile strength
, density
, ductility
, formability, workability, weldability
, and corrosion
resistance, to name a few. A brief historical overview of alloys and manufacturing technologies is given in Ref. Aluminium alloys are used extensively in aircraft due to their high strength-to-weight ratio. On the other hand, pure aluminium metal is much too soft for such uses, and it does not have the high tensile strength that is needed for airplanes and helicopter
s.
of about 70 GPa
, which is about one-third of the elastic modulus of most kinds of steel
and steel alloys. Therefore, for a given load, a component or unit made of an aluminium alloy will experience a greater elastic deformation than a steel part of the identical size and shape. Though there are aluminium alloys with somewhat-higher tensile strengths than the commonly used kinds of steel, simply replacing a steel part with an aluminium alloy might lead to problems.
With completely new metal products, the design choices are often governed by the choice of manufacturing technology. Extrusions are particularly important in this regard, owing to the ease with which aluminium alloys, particularly the Al-Mg-Si series, can be extruded to form complex profiles.
In general, stiffer and lighter designs can be achieved with aluminium alloys than is feasible with steels. For instance, consider the bending of a thin-walled tube: the second moment of area
is inversely related to the stress in the tube wall, i.e. stresses are lower for larger values. The second moment of area is proportional to the cube of the radius times the wall thickness, thus increasing the radius (and weight) by 26% will lead to a halving of the wall stress. For this reason, bicycle frames made of aluminium alloys make use of larger tube diameters than steel or titanium in order to yield the desired stiffness and strength. In automotive engineering, cars made of aluminium alloys employ space frame
s made of extruded profiles to ensure rigidity. This represents a radical change from the common approach for current steel car design, which depend on the body shells for stiffness, that is a unibody design.
Aluminium alloys are widely used in automotive engines, particularly in cylinder block
s and crankcase
s due to the weight savings that are possible. Since aluminium alloys are susceptible to warping at elevated temperatures, the cooling system of such engines is critical. Manufacturing techniques and metallurgical advancements have also been instrumental for the successful application in automotive engines. In the 1960s, the aluminium cylinder head
s and crankcase of the Corvair
earned a reputation for failure and stripping of thread
s, which is not seen in current aluminium cylinder heads.
An important structural limitation of aluminium alloys is their lower fatigue
strength compared to steel. In controlled laboratory conditions, steels display a fatigue limit
, which is the stress amplitude below which no failures occur - the metal does not continue to weaken with extended stress cycles. Aluminum alloys do not have this lower fatigue limit and will continue to weaken with continued stress cycles. Aluminium alloys are therefore sparsely used in parts that require high fatigue strength in the high cycle regime (more than 107 stress cycles).
is used therefore require some expertise, because no visual signs reveal how close the material is to melting.
Aluminium also is subject to internal stresses and strains when it is overheated; the tendency of the metal to creep
under these stresses tends to result in delayed distortions. For example, the warping or cracking of overheated aluminium automobile cylinder heads is commonly observed, sometimes years later, as is the tendency of welded aluminium bicycle frames to gradually twist out of alignment from the stresses of the welding process. Thus, the aerospace industry avoids heat altogether by joining parts with adhesive
s or mechanical fasteners. Adhesive bonding was used in some bicycle frames in the 1970s, with unfortunate results when the aluminium tubing corroded slightly, loosening the adhesive and collapsing the frame.
Stresses in overheated aluminium can be relieved by heat-treating the parts in an oven and gradually cooling it—in effect annealing
the stresses. Yet these parts may still become distorted, so that heat-treating of welded bicycle frames, for instance, can result in a significant fraction becoming misaligned. If the misalignment is not too severe, the cooled parts may be bent into alignment. Of course, if the frame is properly designed for rigidity (see above), that bending will require enormous force.
Aluminium's intolerance to high temperatures has not precluded its use in rocketry; even for use in constructing combustion chambers where gases can reach 3500 K. The Agena
upper stage engine used a regeneratively cooled aluminium design for some parts of the nozzle, including the thermally critical throat region; in fact the extremely high thermal conductivity of aluminium prevented the throat from reaching the melting point even under massive heat flux, resulting in a reliable lightweight component.
in the 1960s, aluminium was introduced at that time for household electrical wiring in North America, even though many fixtures had not been designed to accept aluminium wire. But the new use brought some problems:
All of this resulted in overheated and loose connections, and this in turn resulted in some fires. Builders then became wary of using the wire, and many jurisdictions outlawed its use in very small sizes, in new construction. Yet newer fixtures eventually were introduced with connections designed to avoid loosening and overheating. At first they were marked "Al/Cu", but they now bear a "CO/ALR" coding.
Another way to forestall the heating problem is to crimp the aluminium wire to a short "pigtail
" of copper wire. A properly done high-pressure crimp by the proper tool is tight enough to reduce any thermal expansion of the aluminium. Today, new alloys, designs, and methods are used for aluminium wiring in combination with aluminium terminations.
Cast aluminium alloys use a four to five digit number with a decimal point. The digit in the hundreds place indicates the alloying elements, while the digit after the decimal point indicates the form (cast shape or ingot).
-F : As fabricated
-H : Strain hardened (cold worked) with or without thermal treatment
-O : Full soft (annealed)
-T : Heat treated to produce stable tempers
-W : Solution heat treated only.
Note: -W is a relatively soft intermediary designation that applies after heat treat and before aging is completed. The -W condition can be extended at extremely low temperatures but not indefinitely and depending on the material will typically last no longer than 15 minutes at ambient temperatures.
Aluminium alloy 5005 is used in decorative and architectural applications that require an anodized finish.
Aluminium alloys 5052, 5251, 5754 are very similar grades, only differing in the amount of magnesium. 5052 has 2.5% magnesium and is commonly used in the U.S.; 5251 has 2% magnesium and is commonly used in the UK; and 5754 has 3% magnesium and is commonly used in Europe. Due to their formability, corrosion resistance and weldability these grades are commonly used in pressure vessels, tanks, fitting, boat hulls, and van bodies. Their salt water corrosion resistance is better than the 1200 grade and their strength is better than the 3003 grade.
is an aluminium alloy suitable for cryogenic
applications down to design temperatures of −165 C, since alloys of this type do not show the ductile-brittle transition phenomenon.
The addition of scandium
to aluminium creates nanoscale Al3Sc precipitates which limit the excessive grain growth that occurs in the heat-affected zone of welded aluminium components. This has two beneficial effects: the precipitated Al3Sc forms smaller crystals than are formed in other aluminium alloys and the width of precipitate-free zones that normally exist at the grain boundaries of age-hardenenable aluminium alloys is reduced. Scandium is also a potent grain refiner in cast aluminium alloys, and atom for atom, the most potent strengthener in aluminium, both as a result of grain refinement and precipitation strengthening. However, titanium alloy
s, which are stronger but heavier, are cheaper and much more widely used.
The main application of metallic scandium by weight is in aluminium-scandium alloys for minor aerospace industry components. These alloys contain between 0.1% and 0.5% (by weight) of scandium. They were used in the Russian military aircraft Mig 21 and Mig 29.
Some items of sports equipment, which rely on high performance materials, have been made with scandium-aluminium alloys, including baseball bat
s
,
lacrosse
sticks, as well as bicycle
frames and components, and tent poles.
U.S. gunmaker Smith & Wesson
produces revolvers with frames composed of scandium alloy and cylinders of titanium.
and other aerospace
structures:
Note that the term aircraft aluminium or aerospace aluminium usually refers to 7075.
The following list of aluminium alloys are currently produced, but less widely used:
6082 ,5183,4043 also use in marine
Automobile frames often use 5182 aluminum or 5754 aluminum formed sheets, 6061 or 6063 extrusions.
Wheels have been cast from A365.0 aluminum or formed 5xxx sheet.
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
(Al) is the predominant metal. The typical alloying elements are copper
Copper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
, magnesium
Magnesium
Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...
, manganese
Manganese
Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...
, silicon
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
and zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...
. There are two principal classifications, namely casting
Casting
In metalworking, casting involves pouring liquid metal into a mold, which contains a hollow cavity of the desired shape, and then allowing it to cool and solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process...
alloys and wrought alloys, both of which are further subdivided into the categories heat-treatable
Heat treatment
Heat treating is a group of industrial and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are also used in the manufacture of many other materials, such as glass...
and non-heat-treatable. About 85% of aluminium is used for wrought products, for example rolled plate, foils and extrusions. Cast aluminium alloys yield cost effective products due to the low melting point, although they generally have lower tensile strength
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...
s than wrought alloys. The most important cast aluminium alloy system is Al-Si, where the high levels of silicon (4.0% to 13%) contribute to give good casting characteristics. Aluminium alloys are widely used in engineering structures and components where light weight or corrosion resistance is required.
Alloys composed mostly of the two lightweight metals aluminium and magnesium have been very important in aerospace manufacturing since somewhat before 1940. Aluminium-magnesium alloys are both lighter than other aluminium alloys and much less flammable than alloys that contain a very high percentage of magnesium.
Aluminium alloy surfaces will keep their apparent shine in a dry environment due to the formation of a clear, protective layer of aluminium oxide
Aluminium oxide
Aluminium oxide is an amphoteric oxide with the chemical formula 23. It is commonly referred to as alumina, or corundum in its crystalline form, as well as many other names, reflecting its widespread occurrence in nature and industry...
. In a wet environment, galvanic corrosion can occur when an aluminium alloy is placed in electrical contact with other metals with more negative corrosion potentials than aluminium.
Aluminium alloy compositions are registered with The Aluminum Association
The Aluminum Association
The Aluminum Association is a trade association for the aluminum production, fabrication and recycling industries, and their suppliers. The Association is a 501 non-profit organization based in Arlington, Virginia, United States. The Aluminum Association is a trade association for the aluminum...
. Many organizations publish more specific standards for the manufacture of aluminium alloy, including the Society of Automotive Engineers standards organization, specifically its aerospace standards subgroups, and ASTM International
ASTM International
ASTM International, known until 2001 as the American Society for Testing and Materials , is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services...
.
Overview
Aluminium alloys with a wide range of properties are used in engineering structures. Alloy systems are classified by a number system (ANSIAnsi
Ansi is a village in Kaarma Parish, Saare County, on the island of Saaremaa, Estonia....
) or by names indicating their main alloying constituents (DIN
Din
DIN or Din or din can have several meanings:* A din is a loud noise.* Dīn, an Arabic term meaning "religion" or "way of life".* Din is one of the ten aspects of the Ein Sof in Kabbalah ....
and ISO). Selecting the right alloy for a given application entails considerations of its tensile strength
Tensile strength
Ultimate tensile strength , often shortened to tensile strength or ultimate strength, is the maximum stress that a material can withstand while being stretched or pulled before necking, which is when the specimen's cross-section starts to significantly contract...
, density
Density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...
, ductility
Ductility
In materials science, ductility is a solid material's ability to deform under tensile stress; this is often characterized by the material's ability to be stretched into a wire. Malleability, a similar property, is a material's ability to deform under compressive stress; this is often characterized...
, formability, workability, weldability
Weldability
The weldability, also known as joinability, of a material refers to its ability to be welded. Many metals and thermoplastics can be welded, but some are easier to weld than others...
, and corrosion
Corrosion
Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen...
resistance, to name a few. A brief historical overview of alloys and manufacturing technologies is given in Ref. Aluminium alloys are used extensively in aircraft due to their high strength-to-weight ratio. On the other hand, pure aluminium metal is much too soft for such uses, and it does not have the high tensile strength that is needed for airplanes and helicopter
Helicopter
A helicopter is a type of rotorcraft in which lift and thrust are supplied by one or more engine-driven rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forwards, backwards, and laterally...
s.
Aluminium alloys versus types of steel
Aluminium alloys typically have an elastic modulusElastic modulus
An elastic modulus, or modulus of elasticity, is the mathematical description of an object or substance's tendency to be deformed elastically when a force is applied to it...
of about 70 GPa
Pascal (unit)
The pascal is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force per unit area, defined as one newton per square metre...
, which is about one-third of the elastic modulus of most kinds of steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
and steel alloys. Therefore, for a given load, a component or unit made of an aluminium alloy will experience a greater elastic deformation than a steel part of the identical size and shape. Though there are aluminium alloys with somewhat-higher tensile strengths than the commonly used kinds of steel, simply replacing a steel part with an aluminium alloy might lead to problems.
With completely new metal products, the design choices are often governed by the choice of manufacturing technology. Extrusions are particularly important in this regard, owing to the ease with which aluminium alloys, particularly the Al-Mg-Si series, can be extruded to form complex profiles.
In general, stiffer and lighter designs can be achieved with aluminium alloys than is feasible with steels. For instance, consider the bending of a thin-walled tube: the second moment of area
Second moment of area
The second moment of area, also known as the area moment of inertia, moment of inertia of plane area, or second moment of inertia is a property of a cross section that can be used to predict the resistance of beams to bending and deflection, around an axis that lies in the cross-sectional plane...
is inversely related to the stress in the tube wall, i.e. stresses are lower for larger values. The second moment of area is proportional to the cube of the radius times the wall thickness, thus increasing the radius (and weight) by 26% will lead to a halving of the wall stress. For this reason, bicycle frames made of aluminium alloys make use of larger tube diameters than steel or titanium in order to yield the desired stiffness and strength. In automotive engineering, cars made of aluminium alloys employ space frame
Space frame
A space frame or space structure is a truss-like, lightweight rigid structure constructed from interlocking struts in a geometric pattern. Space frames can be used to span large areas with few interior supports...
s made of extruded profiles to ensure rigidity. This represents a radical change from the common approach for current steel car design, which depend on the body shells for stiffness, that is a unibody design.
Aluminium alloys are widely used in automotive engines, particularly in cylinder block
Cylinder block
A cylinder block is an integrated structure comprising the cylinder of a reciprocating engine and often some or all of their associated surrounding structures...
s and crankcase
Crankcase
In an internal combustion engine of the reciprocating type, the crankcase is the housing for the crankshaft. The enclosure forms the largest cavity in the engine and is located below the cylinder, which in a multicylinder engine are usually integrated into one or several cylinder blocks...
s due to the weight savings that are possible. Since aluminium alloys are susceptible to warping at elevated temperatures, the cooling system of such engines is critical. Manufacturing techniques and metallurgical advancements have also been instrumental for the successful application in automotive engines. In the 1960s, the aluminium cylinder head
Cylinder head
In an internal combustion engine, the cylinder head sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket...
s and crankcase of the Corvair
Chevrolet Corvair
-First generation :The 1960 Corvair 500 and 700 series four-door sedans were conceived as economy cars offering few amenities in order to keep the price competitive, with the 500 selling for under $2,000...
earned a reputation for failure and stripping of thread
Screw thread
A screw thread, often shortened to thread, is a helical structure used to convert between rotational and linear movement or force. A screw thread is a ridge wrapped around a cylinder or cone in the form of a helix, with the former being called a straight thread and the latter called a tapered thread...
s, which is not seen in current aluminium cylinder heads.
An important structural limitation of aluminium alloys is their lower fatigue
Fatigue (material)
'In materials science, fatigue is the progressive and localized structural damage that occurs when a material is subjected to cyclic loading. The nominal maximum stress values are less than the ultimate tensile stress limit, and may be below the yield stress limit of the material.Fatigue occurs...
strength compared to steel. In controlled laboratory conditions, steels display a fatigue limit
Fatigue limit
Fatigue limit, endurance limit, and fatigue strength are all expressions used to describe a property of materials: the amplitude of cyclic stress that can be applied to the material without causing fatigue failure. Ferrous alloys and titanium alloys have a distinct limit, an amplitude below which...
, which is the stress amplitude below which no failures occur - the metal does not continue to weaken with extended stress cycles. Aluminum alloys do not have this lower fatigue limit and will continue to weaken with continued stress cycles. Aluminium alloys are therefore sparsely used in parts that require high fatigue strength in the high cycle regime (more than 107 stress cycles).
Heat sensitivity considerations
Often, the metal's sensitivity to heat must also be considered. Even a relatively routine workshop procedure involving heating is complicated by the fact that aluminium, unlike steel, will melt without first glowing red. Forming operations where a blow torchBlow torch
A blowtorch , blow torch , or blowlamp is a tool for applying lower-intensity and more diffuse flame and heat for various applications, than the oxyacetylene torch. Before aerosol cans and pressurized gas cylinders, fuel was pressurized by a syringe or pump...
is used therefore require some expertise, because no visual signs reveal how close the material is to melting.
Aluminium also is subject to internal stresses and strains when it is overheated; the tendency of the metal to creep
Creep (deformation)
In materials science, creep is the tendency of a solid material to slowly move or deform permanently under the influence of stresses. It occurs as a result of long term exposure to high levels of stress that are below the yield strength of the material....
under these stresses tends to result in delayed distortions. For example, the warping or cracking of overheated aluminium automobile cylinder heads is commonly observed, sometimes years later, as is the tendency of welded aluminium bicycle frames to gradually twist out of alignment from the stresses of the welding process. Thus, the aerospace industry avoids heat altogether by joining parts with adhesive
Adhesive
An adhesive, or glue, is a mixture in a liquid or semi-liquid state that adheres or bonds items together. Adhesives may come from either natural or synthetic sources. The types of materials that can be bonded are vast but they are especially useful for bonding thin materials...
s or mechanical fasteners. Adhesive bonding was used in some bicycle frames in the 1970s, with unfortunate results when the aluminium tubing corroded slightly, loosening the adhesive and collapsing the frame.
Stresses in overheated aluminium can be relieved by heat-treating the parts in an oven and gradually cooling it—in effect annealing
Annealing (metallurgy)
Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered, causing changes in its properties such as strength and hardness. It is a process that produces conditions by heating to above the recrystallization temperature, maintaining a suitable temperature, and...
the stresses. Yet these parts may still become distorted, so that heat-treating of welded bicycle frames, for instance, can result in a significant fraction becoming misaligned. If the misalignment is not too severe, the cooled parts may be bent into alignment. Of course, if the frame is properly designed for rigidity (see above), that bending will require enormous force.
Aluminium's intolerance to high temperatures has not precluded its use in rocketry; even for use in constructing combustion chambers where gases can reach 3500 K. The Agena
RM-81 Agena
The RM-81 Agena was an American rocket upper stage and satellite support bus which was developed by Lockheed initially for the canceled WS-117L reconnaissance satellite program...
upper stage engine used a regeneratively cooled aluminium design for some parts of the nozzle, including the thermally critical throat region; in fact the extremely high thermal conductivity of aluminium prevented the throat from reaching the melting point even under massive heat flux, resulting in a reliable lightweight component.
Household wiring
Because of its high conductivity and relatively low price compared with copperCopper
Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish...
in the 1960s, aluminium was introduced at that time for household electrical wiring in North America, even though many fixtures had not been designed to accept aluminium wire. But the new use brought some problems:
- The greater coefficient of thermal expansion of aluminium causes the wire to expand and contract relative to the dissimilar metal screwScrewA screw, or bolt, is a type of fastener characterized by a helical ridge, known as an external thread or just thread, wrapped around a cylinder. Some screw threads are designed to mate with a complementary thread, known as an internal thread, often in the form of a nut or an object that has the...
connection, eventually loosening the connection.
- Pure aluminium has a tendency to "creep" under steady sustained pressure (to a greater degree as the temperature rises), again loosening the connection.
- Galvanic corrosion from the dissimilar metals increases the electrical resistance of the connection.
All of this resulted in overheated and loose connections, and this in turn resulted in some fires. Builders then became wary of using the wire, and many jurisdictions outlawed its use in very small sizes, in new construction. Yet newer fixtures eventually were introduced with connections designed to avoid loosening and overheating. At first they were marked "Al/Cu", but they now bear a "CO/ALR" coding.
Another way to forestall the heating problem is to crimp the aluminium wire to a short "pigtail
Patch cable
A patch cable or patch cord is an electrical or optical cable used to connect one electronic or optical device to another for signal routing. Devices of different types are connected with patch cords...
" of copper wire. A properly done high-pressure crimp by the proper tool is tight enough to reduce any thermal expansion of the aluminium. Today, new alloys, designs, and methods are used for aluminium wiring in combination with aluminium terminations.
Alloy designations
Wrought and cast aluminium alloys use different identification systems. Wrought aluminium is identified with a four digit number which identifies the alloying elements.Cast aluminium alloys use a four to five digit number with a decimal point. The digit in the hundreds place indicates the alloying elements, while the digit after the decimal point indicates the form (cast shape or ingot).
Temper designation
The temper designation follows the cast or wrought designation number with a dash, a letter, and potentially a one to three digit number, e.g. 6061-T6. The definitions for the tempers are:-F : As fabricated
-H : Strain hardened (cold worked) with or without thermal treatment
-
- -H1 : Strain hardened without thermal treatment
- -H2 : Strain hardened and partially annealed
- -H3 : Strain hardened and stabilized by low temperature heating
-
- Second digit : A second digit denotes the degree of hardness
- -HX2 = 1/4 hard
- -HX4 = 1/2 hard
- -HX6 = 3/4 hard
- -HX8 = full hard
- -HX9 = extra hard
-O : Full soft (annealed)
-T : Heat treated to produce stable tempers
-
- -T1 : Cooled from hot working and naturally aged (at room temperature)
- -T2 : Cooled from hot working, cold-worked, and naturally aged
- -T3 : Solution heat treated and cold worked
- -T4 : Solution heat treated and naturally aged
- -T5 : Cooled from hot working and artificially aged (at elevated temperature)
-
- -T51 : Stress relieved by stretching
-
- -T510 : No further straightening after stretching
- -T511 : Minor straightening after stretching
- -T52 : Stress relieved by thermal treatment
- -T6 : Solution heat treated and artificially aged
- -T7 : Solution heat treated and stabilized
- -T8 : Solution heat treated, cold worked, and artificially aged
- -T9 : Solution heat treated, artificially aged, and cold worked
- -T10 : Cooled from hot working, cold-worked, and artificially aged
-W : Solution heat treated only.
Note: -W is a relatively soft intermediary designation that applies after heat treat and before aging is completed. The -W condition can be extended at extremely low temperatures but not indefinitely and depending on the material will typically last no longer than 15 minutes at ambient temperatures.
Wrought alloys
The International Alloy Designation System is the most widely accepted naming scheme for wrought alloys. Each alloy is given a four-digit number, where the first digit indicates the major alloying elements.- 1000 series are essentially pure aluminium with a minimum 99% aluminium content by weight and can be work hardened.
- 2000 series are alloyed with copper, can be precipitation hardened to strengths comparable to steelSteelSteel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
. Formerly referred to as duraluminDuraluminDuralumin is the trade name of one of the earliest types of age-hardenable aluminium alloys. The main alloying constituents are copper, manganese, and magnesium. A commonly used modern equivalent of this alloy type is AA2024, which contains 4.4% copper, 1.5% magnesium, 0.6% manganese and 93.5%...
, they were once the most common aerospace alloys, but were susceptible to stress corrosion crackingStress corrosion crackingStress corrosion cracking is the unexpected sudden failure of normally ductile metals subjected to a tensile stress in a corrosive environment, especially at elevated temperature in the case of metals. SCC is highly chemically specific in that certain alloys are likely to undergo SCC only when...
and are increasingly replaced by 7000 series in new designs. - 3000 series are alloyed with manganese, and can be work hardened.
- 4000 series are alloyed with silicon. They are also known as siluminSiluminSilumin is a series of lightweight, high-strength aluminium alloys with silicon content of 13%. Among the advantages of silumin is its high resistance to corrosion, making it useful in humid environments...
. - 5000 series are alloyed with magnesium.
- 6000 series are alloyed with magnesium and silicon, are easy to machine, and can be precipitation hardened, but not to the high strengths that 2000 and 7000 can reach.
- 7000 series are alloyed with zinc, and can be precipitation hardened to the highest strengths of any aluminium alloy.
- 8000 series is a category mainly used for lithium alloys.
| Alloy | Si Silicon Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table... |
Fe Iron Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust... |
Cu Copper Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductile metal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish... |
Mn Manganese Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals... |
Mg Magnesium Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole... |
Cr Chromium Chromium is a chemical element which has the symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard metal that takes a high polish and has a high melting point. It is also odorless, tasteless, and malleable... |
Zn Zinc Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2... |
V Vanadium Vanadium is a chemical element with the symbol V and atomic number 23. It is a hard, silvery gray, ductile and malleable transition metal. The formation of an oxide layer stabilizes the metal against oxidation. The element is found only in chemically combined form in nature... |
Ti Titanium Titanium is a chemical element with the symbol Ti and atomic number 22. It has a low density and is a strong, lustrous, corrosion-resistant transition metal with a silver color.... |
Bi Bismuth Bismuth is a chemical element with symbol Bi and atomic number 83. Bismuth, a trivalent poor metal, chemically resembles arsenic and antimony. Elemental bismuth may occur naturally uncombined, although its sulfide and oxide form important commercial ores. The free element is 86% as dense as lead... |
Ga Gallium Gallium is a chemical element that has the symbol Ga and atomic number 31. Elemental gallium does not occur in nature, but as the gallium salt in trace amounts in bauxite and zinc ores. A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures. As it liquefies... |
Pb Lead Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed... |
Zr Zirconium Zirconium is a chemical element with the symbol Zr and atomic number 40. The name of zirconium is taken from the mineral zircon. Its atomic mass is 91.224. It is a lustrous, grey-white, strong transition metal that resembles titanium... |
Limits†† | Al | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Each | Total | |||||||||||||||
| 1050 | 0.25 | 0.40 | 0.05 | 0.05 | 0.05 | 0.05 | 0.03 | 99.5 min | ||||||||
| 1060 | 0.25 | 0.35 | 0.05 | 0.03 | 0.03 | 0.03 | 0.05 | 0.05 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 99.6 min | |
| 1100 | 0.95 Si+Fe | 0.05–0.20 | 0.05 | 0.10 | 0.05 | 0.15 | 99.0 min | |||||||||
| 1199 | 0.006 | 0.006 | 0.006 | 0.002 | 0.006 | 0.006 | 0.005 | 0.002 | 0.005 | 0.002 | 99.99 min | |||||
| 2014 | 0.50–1.2 | 0.7 | 3.9–5.0 | 0.40–1.2 | 0.20–0.8 | 0.10 | 0.25 | 0.15 | 0.05 | 0.15 | remainder | |||||
| 2024 | 0.50 | 0.50 | 3.8–4.9 | 0.30–0.9 | 1.2–1.8 | 0.10 | 0.25 | 0.15 | 0.05 | 0.15 | remainder | |||||
| 2219 | 0.2 | 0.30 | 5.8–6.8 | 0.20–0.40 | 0.02 | 0.10 | 0.05–0.15 | 0.02–0.10 | 0.10–0.25 | 0.05 | 0.15 | remainder | ||||
| 3003 | 0.6 | 0.7 | 0.05–0.20 | 1.0–1.5 | 0.10 | 0.05 | 0.15 | remainder | ||||||||
| 3004 | 0.30 | 0.7 | 0.25 | 1.0–1.5 | 0.8–1.3 | 0.25 | 0.05 | 0.15 | remainder | |||||||
| 3102 | 0.40 | 0.7 | 0.10 | 0.05–0.40 | 0.30 | 0.10 | 0.05 | 0.15 | remainder | |||||||
| 4043 | 4.5–6.0 | 0.80 | 0.30 | 0.05 | 0.05 | 0.10 | 0.20 | 0.05 | 0.15 | remainder | ||||||
| 5052 | 0.25 | 0.40 | 0.10 | 0.10 | 2.2–2.8 | 0.15–0.35 | 0.10 | 0.05 | 0.15 | remainder | ||||||
| 5083 | 0.40 | 0.40 | 0.10 | 0.40–1.0 | 4.0–4.9 | 0.05–0.25 | 0.25 | 0.15 | 0.05 | 0.15 | remainder | |||||
| 5086 | 0.40 | 0.50 | 0.10 | 0.20–0.7 | 3.5–4.5 | 0.05–0.25 | 0.25 | 0.15 | 0.05 | 0.15 | remainder | |||||
| 5154 | 0.25 | 0.40 | 0.10 | 0.10 | 3.10–3.90 | 0.15–0.35 | 0.20 | 0.20 | 0.05 | 0.15 | remainder | |||||
| 5356 | 0.25 | 0.40 | 0.10 | 0.10 | 4.50–5.50 | 0.05–0.20 | 0.10 | 0.06–0.20 | 0.05 | 0.15 | remainder | |||||
| 5454 | 0.25 | 0.40 | 0.10 | 0.50–1.0 | 2.4–3.0 | 0.05–0.20 | 0.25 | 0.20 | 0.05 | 0.15 | remainder | |||||
| 5456 | 0.25 | 0.40 | 0.10 | 0.50–1.0 | 4.7–5.5 | 0.05–0.20 | 0.25 | 0.20 | 0.05 | 0.15 | remainder | |||||
| 5754 | 0.40 | 0.40 | 0.10 | 0.50 | 2.6–3.6 | 0.30 | 0.20 | 0.15 | 0.05 | 0.15 | remainder | |||||
| 6005 | 0.6–0.9 | 0.35 | 0.10 | 0.10 | 0.40–0.6 | 0.10 | 0.10 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 6005A† | 0.50–0.9 | 0.35 | 0.30 | 0.50 | 0.40–0.7 | 0.30 | 0.20 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 6060 | 0.30–0.6 | 0.10–0.30 | 0.10 | 0.10 | 0.35–0.6 | 0.05 | 0.15 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 6061 | 0.40–0.8 | 0.7 | 0.15–0.40 | 0.15 | 0.8–1.2 | 0.04–0.35 | 0.25 | 0.15 | 0.05 | 0.15 | remainder | |||||
| 6063 | 0.20–0.6 | 0.35 | 0.10 | 0.10 | 0.45–0.9 | 0.10 | 0.10 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 6066 | 0.9–1.8 | 0.50 | 0.7–1.2 | 0.6–1.1 | 0.8–1.4 | 0.40 | 0.25 | 0.20 | 0.05 | 0.15 | remainder | |||||
| 6070 | 1.0–1.7 | 0.50 | 0.15–0.40 | 0.40–1.0 | 0.50–1.2 | 0.10 | 0.25 | 0.15 | 0.05 | 0.15 | remainder | |||||
| 6082 | 0.7–1.3 | 0.50 | 0.10 | 0.40–1.0 | 0.60–1.2 | 0.25 | 0.20 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 6105 | 0.6–1.0 | 0.35 | 0.10 | 0.10 | 0.45–0.8 | 0.10 | 0.10 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 6162 | 0.40–0.8 | 0.50 | 0.20 | 0.10 | 0.7–1.1 | 0.10 | 0.25 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 6262 | 0.40–0.8 | 0.7 | 0.15–0.40 | 0.15 | 0.8–1.2 | 0.04–0.14 | 0.25 | 0.15 | 0.40–0.7 | 0.40–0.7 | 0.05 | 0.15 | remainder | |||
| 6351 | 0.7–1.3 | 0.50 | 0.10 | 0.40–0.8 | 0.40–0.8 | 0.20 | 0.20 | 0.05 | 0.15 | remainder | ||||||
| 6463 | 0.20–0.6 | 0.15 | 0.20 | 0.05 | 0.45–0.9 | 0.05 | 0.05 | 0.15 | remainder | |||||||
| 7005 | 0.35 | 0.40 | 0.10 | 0.20–0.70 | 1.0–1.8 | 0.06–0.20 | 4.0–5.0 | 0.01–0.06 | 0.08–0.20 | 0.05 | 0.15 | remainder | ||||
| 7022 | 0.50 | 0.50 | 0.50-1.00 | 0.10–0.40 | 2.60–3.70 | 0.10–0.30 | 4.30–5.20 | 0.20 | 0.05 | 0.15 | remainder | |||||
| 7072 | 0.7 Si+Fe | 0.10 | 0.10 | 0.10 | 0.8–1.3 | 0.05 | 0.15 | remainder | ||||||||
| 7075 | 0.40 | 0.50 | 1.2–2.0 | 0.30 | 2.1–2.9 | 0.18–0.28 | 5.1–6.1 | 0.20 | 0.05 | 0.15 | remainder | |||||
| 7079 | 0.3 | 0.40 | 0.40–0.80 | 0.10–0.30 | 2.9–3.7 | 0.10–0.25 | 3.8–4.8 | 0.10 | 0.05 | 0.15 | remainder | |||||
| 7116 | 0.15 | 0.30 | 0.50–1.1 | 0.05 | 0.8–1.4 | 4.2–5.2 | 0.05 | 0.05 | 0.03 | 0.05 | 0.15 | remainder | ||||
| 7129 | 0.15 | 0.30 | 0.50–0.9 | 0.10 | 1.3–2.0 | 0.10 | 4.2–5.2 | 0.05 | 0.05 | 0.03 | 0.05 | 0.15 | remainder | |||
| 7178 | 0.40 | 0.50 | 1.6–2.4 | 0.30 | 2.4–3.1 | 0.18–0.28 | 6.3–7.3 | 0.20 | 0.05 | 0.15 | remainder | |||||
| †Manganese plus chromium must be between 0.12–0.50%.††This column lists the limits that apply to all elements, whether a table column exists for them or not, for which no other limits are specified. | ||||||||||||||||
5005
Aluminium alloy 5005 is used in decorative and architectural applications that require an anodized finish.
5052/5251/5754
Aluminium alloys 5052, 5251, 5754 are very similar grades, only differing in the amount of magnesium. 5052 has 2.5% magnesium and is commonly used in the U.S.; 5251 has 2% magnesium and is commonly used in the UK; and 5754 has 3% magnesium and is commonly used in Europe. Due to their formability, corrosion resistance and weldability these grades are commonly used in pressure vessels, tanks, fitting, boat hulls, and van bodies. Their salt water corrosion resistance is better than the 1200 grade and their strength is better than the 3003 grade.
5083
is an aluminium alloy suitable for cryogenic
Cryogenics
In physics, cryogenics is the study of the production of very low temperature and the behavior of materials at those temperatures. A person who studies elements under extremely cold temperature is called a cryogenicist. Rather than the relative temperature scales of Celsius and Fahrenheit,...
applications down to design temperatures of −165 C, since alloys of this type do not show the ductile-brittle transition phenomenon.
Cast alloys
The Aluminium Association (AA) has adopted a nomenclature similar to that of wrought alloys. British Standard and DIN have different designations. In the AA system, the second two digits reveal the minimum percentage of aluminium, e.g. 150.x correspond to a minimum of 99.50% aluminium. The digit after the decimal point takes a value of 0 or 1, denoting casting and ingot respectively. The main alloying elements in the AA system are as follows:- 1xx.x series are minimum 99% aluminium
- 2xx.x series copper
- 3xx.x series silicon, copper and/or magnesium
- 4xx.x series silicon
- 5xx.x series magnesium
- 7xx.x series zinc
- 8xx.x series lithium
| Alloy type | | Temper | | Tensile strength (min) [ksi] ([MPa]) | | Yield strength (min) [ksi] ([MPa]) | | Elongation in 2 in [%] | |
|---|---|---|---|---|---|
| ANSI | UNS | ||||
| 201.0 | A02010 | T7 | 60 (413.7 kPa) | 50 (344.7 kPa) | 3.0 |
| 204.0 | A02040 | T4 | 45 (310.3 kPa) | 28 (193.1 kPa) | 6.0 |
| 242.0 | A02420 | O | 23 (158.6 kPa) | N/A | N/A |
| T61 | 32 (220.6 kPa) | 20 (137.9 kPa) | N/A | ||
| A242.0 | A12420 | T75 | 29 (199.9 kPa) | N/A | 1.0 |
| 295.0 | A02950 | T4 | 29 (199.9 kPa) | 13 (89.6 kPa) | 6.0 |
| T6 | 32 (220.6 kPa) | 20 (137.9 kPa) | 3.0 | ||
| T62 | 36 (248.2 kPa) | 28 (193.1 kPa) | N/A | ||
| T7 | 29 (199.9 kPa) | 16 (110.3 kPa) | 3.0 | ||
| 319.0 | A03190 | F | 23 (158.6 kPa) | 13 (89.6 kPa) | 1.5 |
| T5 | 25 (172.4 kPa) | N/A | N/A | ||
| T6 | 31 (213.7 kPa) | 20 (137.9 kPa) | 1.5 | ||
| 328.0 | A03280 | F | 25 (172.4 kPa) | 14 (96.5 kPa) | 1.0 |
| T6 | 34 (234.4 kPa) | 21 (144.8 kPa) | 1.0 | ||
| 355.0 | A03550 | T6 | 32 (220.6 kPa) | 20 (137.9 kPa) | 2.0 |
| T51 | 25 (172.4 kPa) | 18 (124.1 kPa) | N/A | ||
| T71 | 30 (206.8 kPa) | 22 (151.7 kPa) | N/A | ||
| C355.0 | A33550 | T6 | 36 (248.2 kPa) | 25 (172.4 kPa) | 2.5 |
| 356.0 | A03560 | F | 19 (131 kPa) | 9.5 (65.5 kPa) | 2.0 |
| T6 | 30 (206.8 kPa) | 20 (137.9 kPa) | 3.0 | ||
| T7 | 31 (213.7 kPa) | N/A | N/A | ||
| T51 | 23 (158.6 kPa) | 16 (110.3 kPa) | N/A | ||
| T71 | 25 (172.4 kPa) | 18 (124.1 kPa) | 3.0 | ||
| A356.0 | A13560 | T6 | 34 (234.4 kPa) | 24 (165.5 kPa) | 3.5 |
| T61 | 35 (241.3 kPa) | 26 (179.3 kPa) | 1.0 | ||
| 443.0 | A04430 | F | 17 (117.2 kPa) | 7 (48.3 kPa) | 3.0 |
| B443.0 | A24430 | F | 17 (117.2 kPa) | 6 (41.4 kPa) | 3.0 |
| 512.0 | A05120 | F | 17 (117.2 kPa) | 10 (68.9 kPa) | N/A |
| 514.0 | A05140 | F | 22 (151.7 kPa) | 9 (62.1 kPa) | 6.0 |
| 520.0 | A05200 | T4 | 42 (289.6 kPa) | 22 (151.7 kPa) | 12.0 |
| 535.0 | A05350 | F | 35 (241.3 kPa) | 18 (124.1 kPa) | 9.0 |
| 705.0 | A07050 | T5 | 30 (206.8 kPa) | 17 (117.2 kPa)† | 5.0 |
| 707.0 | A07070 | T7 | 37 (255.1 kPa) | 30 (206.8 kPa)† | 1.0 |
| 710.0 | A07100 | T5 | 32 (220.6 kPa) | 20 (137.9 kPa) | 2.0 |
| 712.0 | A07120 | T5 | 34 (234.4 kPa) | 25 (172.4 kPa)† | 4.0 |
| 713.0 | A07130 | T5 | 32 (220.6 kPa) | 22 (151.7 kPa) | 3.0 |
| 771.0 | A07710 | T5 | 42 (289.6 kPa) | 38 (262 kPa) | 1.5 |
| T51 | 32 (220.6 kPa) | 27 (186.2 kPa) | 3.0 | ||
| T52 | 36 (248.2 kPa) | 30 (206.8 kPa) | 1.5 | ||
| T6 | 42 (289.6 kPa) | 35 (241.3 kPa) | 5.0 | ||
| T71 | 48 (330.9 kPa) | 45 (310.3 kPa) | 5.0 | ||
| 850.0 | A08500 | T5 | 16 (110.3 kPa) | N/A | 5.0 |
| 851.0 | A08510 | T5 | 17 (117.2 kPa) | N/A | 3.0 |
| 852.0 | A08520 | T5 | 24 (165.5 kPa) | 18 (124.1 kPa) | N/A |
| †Only when requested by the customer | |||||
Named alloys
- AlcladAlcladAlclad is a trademark of Alcoa used as a generic term to describe corrosion resistant aluminium sheet formed from high-purity aluminium surface layers metallurgically bonded to high strength aluminium alloy core material. These sheets are commonly used by the aircraft industry...
Aluminium sheet formed from high-purity aluminium surface layers bonded to high strength aluminium alloy core material - BirmabrightBirmabrightBirmabright is a trade name of the former Birmetals Co. for various types of lightweight sheet metal in an alloy of aluminium and magnesium. The constituents are 7% magnesium, sometimes 1% manganese, and the remainder aluminium...
(aluminium, magnesium) a product of The Birmetals Company, basically equivalent to 5251 - DuraluminDuraluminDuralumin is the trade name of one of the earliest types of age-hardenable aluminium alloys. The main alloying constituents are copper, manganese, and magnesium. A commonly used modern equivalent of this alloy type is AA2024, which contains 4.4% copper, 1.5% magnesium, 0.6% manganese and 93.5%...
(copper, aluminium) - MagnaliumMagnaliumMagnalium is an aluminium alloy with 1.5 to 2% magnesium and small amounts of copper, nickel, and tin. Some alloys, intended for particular uses at the cost of poor corrosion resistance, may consist of up to 50% magnesium...
- MagnoxMagnox (alloy)Magnox is an alloy—mainly of magnesium with small amounts of aluminium and other metals—used in cladding unenriched uranium metal fuel with a non-oxidising covering to contain fission products in nuclear reactors....
(magnesium, aluminium) - SiluminSiluminSilumin is a series of lightweight, high-strength aluminium alloys with silicon content of 13%. Among the advantages of silumin is its high resistance to corrosion, making it useful in humid environments...
(aluminium, silicon) - Titanal (aluminium, zinc, magnesium, copper, zirconium) a product of Austria Metall AGAustria Metall AGAMAG is situated in the village of Ranshofen which is in Braunau am Inn and was founded in 1938.It is the biggest company in the Austrian Aluminium industry sector and is part of Constantia Packaging AG.- Companies:...
. Commonly used in high performance sports products, particularly snowboards and skis. - Y alloyY alloyY alloy is a nickel-containing aluminium alloy. It was developed by the National Physical Laboratory during World War I, in attempt to find an aluminium alloy that would retain its strength at high temperatures....
, HiduminiumHiduminiumThe Hiduminium or R.R. alloys are a series of high-strength, high-temperature aluminium alloys, developed for aircraft use by Rolls-Royce before World War II. They were manufactured and later developed by High Duty Alloys Ltd....
, R.R. alloys: pre-war nickel-aluminium alloys, used in aerospace and engine pistons, for their ability to retain strength at elevated temperature.
Scandium-Aluminium
Scandium
Scandium is a chemical element with symbol Sc and atomic number 21. A silvery-white metallic transition metal, it has historically been sometimes classified as a rare earth element, together with yttrium and the lanthanoids...
to aluminium creates nanoscale Al3Sc precipitates which limit the excessive grain growth that occurs in the heat-affected zone of welded aluminium components. This has two beneficial effects: the precipitated Al3Sc forms smaller crystals than are formed in other aluminium alloys and the width of precipitate-free zones that normally exist at the grain boundaries of age-hardenenable aluminium alloys is reduced. Scandium is also a potent grain refiner in cast aluminium alloys, and atom for atom, the most potent strengthener in aluminium, both as a result of grain refinement and precipitation strengthening. However, titanium alloy
Titanium alloy
Titanium alloys are metallic materials which contain a mixture of titanium and other chemical elements. Such alloys have very high tensile strength and toughness , light weight, extraordinary corrosion resistance, and ability to withstand extreme temperatures...
s, which are stronger but heavier, are cheaper and much more widely used.
The main application of metallic scandium by weight is in aluminium-scandium alloys for minor aerospace industry components. These alloys contain between 0.1% and 0.5% (by weight) of scandium. They were used in the Russian military aircraft Mig 21 and Mig 29.
Some items of sports equipment, which rely on high performance materials, have been made with scandium-aluminium alloys, including baseball bat
Baseball bat
A baseball bat is a smooth wooden or metal club used in the game of baseball to hit the ball after the ball is thrown by the pitcher. It is no more than 2.75 inches in diameter at the thickest part and no more than 42 inches in length. It typically weighs no more than 33 ounces , but it...
s
,
lacrosse
Lacrosse
Lacrosse is a team sport of Native American origin played using a small rubber ball and a long-handled stick called a crosse or lacrosse stick, mainly played in the United States and Canada. It is a contact sport which requires padding. The head of the lacrosse stick is strung with loose mesh...
sticks, as well as bicycle
Bicycle
A bicycle, also known as a bike, pushbike or cycle, is a human-powered, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A person who rides a bicycle is called a cyclist, or bicyclist....
frames and components, and tent poles.
U.S. gunmaker Smith & Wesson
Smith & Wesson
Smith & Wesson is the largest manufacturer of handguns in the United States. The corporate headquarters is in Springfield, Massachusetts. Founded in 1852, Smith & Wesson's pistols and revolvers have become standard issue to police and armed forces throughout the world...
produces revolvers with frames composed of scandium alloy and cylinders of titanium.
List of aerospace Aluminium alloys
The following aluminium alloys are commonly used in aircraftAircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...
and other aerospace
Aerospace
Aerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space...
structures:
- 7075 aluminium
- 6061 aluminium
- 6063 aluminium
- 2024 aluminium
- 5052 aluminium
Note that the term aircraft aluminium or aerospace aluminium usually refers to 7075.
The following list of aluminium alloys are currently produced, but less widely used:
- 2090 aluminium
- 2124 aluminium
- 2195 aluminium - Al-LiAl-LiAl-Li alloys are a series of alloys of aluminium and lithium, often also including copper and zirconium. Since lithium is the least dense elemental metal these alloys are significantly less dense than aluminium...
alloy, used in Space Shuttle Super Lightweight external tank - 2219 aluminium - Al-Cu alloy, used in the original Space Shuttle Standard Weight external tank
- 2324 aluminium
- 5059 aluminium5059 aluminium alloy5059 is an aluminium alloy, primarily alloyed with magnesium. It is not strengthened by heat treatment, instead becoming stronger due to strain hardening, or cold mechanical working of the material....
- Used in experimental rocket cryogenic tanks - 6013 aluminium
- 7050 aluminium
- 7055 aluminium
- 7150 aluminium
- 7475 aluminium
Marine alloys
These alloys are used for boat building and shipbuilding, and other marine and salt-water sensitive shore applications.- 5052 aluminium
- 5059 aluminium5059 aluminium alloy5059 is an aluminium alloy, primarily alloyed with magnesium. It is not strengthened by heat treatment, instead becoming stronger due to strain hardening, or cold mechanical working of the material....
- 5083 aluminium
- 5086 aluminium
- 6061 aluminium
- 6063 aluminium
6082 ,5183,4043 also use in marine
Cycling alloys
These alloys are used for cycling frames and components- 2014 aluminium
- 6061 aluminium
- 6063 aluminium
- 7005 aluminium
- 7075 aluminium
- Scandium aluminium
Automotive alloys
6111 aluminium and 2008 aluminum alloy are extensively used for external automotive body panels, with 5083 and 5754 used for inner body panels. Hoods have been manufactured from 2036, 6016, and 6111 alloys. Truck and trailer body panels have used 5456 aluminum.Automobile frames often use 5182 aluminum or 5754 aluminum formed sheets, 6061 or 6063 extrusions.
Wheels have been cast from A365.0 aluminum or formed 5xxx sheet.
External links
- Aluminium alloys for die casting according to the Japanese Standards, China National Standards, U.S. Standards and German Standards
- Aluminium alloys for chill casting and low pressure casting according to the Japanese, Chinese, American and German industrial standard
- Aluminium alloys for extrusion according to the German Standards
- The Aluminium Association's chemical composition standards for wrought aluminium