Uniaxial True Stress-Strain after Necking - Tyco …（柱头后真正单轴应力-应变-泰科u2026）.pdf

Uniaxial True Stress-Strain after Necking Yun Ling AMP Incorporated ABSTRACT its value at the onset of necking, the standard tensile test cannot A weighted-average method for determining uniaxial, provide data sufficient for modeling. This can seriously limit true tensile stress vs. strain relation after necking is the use of FEM for large strain applications such as contact presented for strip shaped samples. The method re- forming. For this reason some method has to be found to obtain quires identification of a lower and an upper bound for the true stress-strain relation after necking. the true stress-strain function after necking and ex- 3 presses the true stress-strain relation as the weighted For rods Bridgman’s correction method is most commonly average of these two bounds. The weight factor is de- used to obtain uniaxial true stress-strain relations after necking. termined iteratively by a finite element model until best Because electrical contacts are almost exclusively in form of agreement between calculated and experimental load- flat bars applicability of the Bridgman correction is rather lim- extension curves is achieved. The method was applied ited. This extends also to laboratory tests, where samples are to various alloys. required that approach in geometry and dimensions those of the