IHS ESDU Generalisation of smooth continuous stress-strain curves for metallic materials. 76016

ESDU 76016 describes a generalised method for representing a smooth stress/strain curve by an equation involving Young's modulus, a reference stress and a characteristic index. The determination of those last two quantities is explained. The method is valid for tension or compression and provides a convenient method for accounting for the behaviour of a material beyond its elastic range, for example in buckling calculations. The method allows simple calculation of tangent and secant modulus and Poisson's ratio but calculation of stress at a given strain or at a ratio of stress to tangent modulus is less easy. For that case approximate equations are given or an exact solution may be obtained using a Fortran program as ESDUpac A7616. Tables list the two constants that define the compressive stress/strain curve for 29 aircraft specification materials.