The standard linear solid (SLS) model, also known as the Zener model, is a method of modeling the behavior of a viscoelastic

Viscoelasticity

Viscoelasticity is the property of materials that exhibit both viscous and elastic characteristics when undergoing deformation. Viscous materials, like honey, resist shear flow and strain linearly with time when a stress is applied. Elastic materials strain instantaneously when stretched and just...

 material using a linear combination of springs and dashpots to represent elastic and viscous components, respectively. Often more similar Maxwell model

Maxwell material

A Maxwell material is a viscoelastic material having the properties both of elasticity and viscosity. It is named for James Clerk Maxwell who proposed the model in 1867. It is also known as a Maxwell fluid.- Definition :...

 and the Kelvin–Voigt model are used. These models are often proved insufficient, however; the Maxwell model does not describe creep, and the Kelvin–Voigt model does not describe stress relaxation.