Mooney–Rivlin solid
In continuum mechanics, a Mooney–Rivlin solid is a hyperelastic material model where the strain energy density function W {\displaystyle W\,} is a linear combination of two invariants of the left Cauchy–Green deformation tensor B {\displaystyle {\boldsymbol {B}}} . The model was proposed by Melvin Mooney in 1940 and expressed in terms of invariants by Ronald Rivlin in 1948.