On Deduceing Uniaxial Stress-Strain Relation from Bend Test

Uniaxial tensile stress-strain relation is an necessary input for Finite Element Analysis and in understanding the material performance.  However, such test is not easy to perform for small wires, microtubings and thin sheet.  Rather, bend tests in general is easier to perform with relaiable repetibilities.  This article provide a general theory to deduce the unaxial material response from bend test.

Application of the theory to Nitinol is demonstrated by a few examples.  A procedure specific to Nitinol is also illustrated with published bend test data.