Nickel pig iron is a low grade ferronickel invented in China as a cheaper alternative to pure nickel for the production of stainless steel

Stainless steel

In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....

. It is composed of low-grade nickel ore, coking coal, and a mixture of gravel

Gravel

Gravel is composed of unconsolidated rock fragments that have a general particle size range and include size classes from granule- to boulder-sized fragments. Gravel can be sub-categorized into granule and cobble...

 and sand as an aggregate

Aggregate (composite)

Aggregate is the component of a composite material that resists compressive stress and provides bulk to the composite material. For efficient filling, aggregate should be much smaller than the finished item, but have a wide variety of sizes...

. This mixture is heated in either a blast furnace

Blast furnace

A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally iron.In a blast furnace, fuel and ore and flux are continuously supplied through the top of the furnace, while air is blown into the bottom of the chamber, so that the chemical reactions...

 or an electric arc furnace

Electric arc furnace

An electric arc furnace is a furnace that heats charged material by means of an electric arc.Arc furnaces range in size from small units of approximately one ton capacity up to about 400 ton units used for secondary steelmaking...

depending on the desired grade. Impurities are then removed via smelting and sintering processes and the resulting nickel pig iron contains four to 13 percent pure nickel.

External links

• A breakthrough in China, another blow for Sudbury