摘要
通过对K08Al、08Al、1Cr13和SPCE—N四种板材进行单向拉仲试验,测定了薄板在拉伸变形过程中表面粗糙度 R_a R_Z R_m值随应变ε_1的变化曲线,并根据Hill和S wift的失稳理论考虑板厚及表面粗糙度变化的作用对失稳应变进行了分析。结果表明,表面粗糙度R_a、R_z、R_m 值均随应变呈线性增长,当考虑表面粗糙度及板厚影响时,失稳应变低于理论值。
The change of surface roughness Ra、Rz、Rm value according to the strain ε_1 during forming process was measured under uniaxial tensile test of four kinds of sheet K08A1,08A1,1Cr13,SPCE-N,and the instability strain with influence of surface roughness was analysed by using instability theories of Hill and Swift. The results show that Ra,Rz,Rm value of surface roughn- ess increases linearly with strain,and instability strain is lower than calcula- ted by theories when considering the influence of surface roughness and thickness.
关键词
薄板
拉伸
试验
粗糙度
失稳
应变
surface roughness
instability
thickness inhomogeneity
