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采用成形试验机和万能材料试验机,对DC01、DC06、HC340LA、HC420LA钢进行了制耳试验和室温拉伸试验,获得了其制耳率和不同计算条件下的塑性应变比各向异性度△r,并分析了△r与Z的关系.分析结果表明,采用单点法测定塑性应变比r值时,r值与应变的路径特征干扰了试样结果的测定,试样结果间的离散性较大,塑性应变比各向异性度△r与制耳率Z无对应关系.采用回归方法测定r值时,可以有效消除r值与应变的路径特征的干扰,塑性应变比各向异性度△r与制耳率Z成比例关系.

Relationship Between Degree of Planar Anisotropy and Earing Ratio

Earing test and tensile test at room temperature on DC01、DC06、HC340LA、HC420LA steels have been carried out on a sheet metal formability testing machine and a material testing machine, and then earing ratio and the degree of planar anisotropy have been obtained; the relationship between earing ratio and the degree of planar anisotropy Δr was discussed. The evolvement tendency of r was significantly influenced by the strain path, leading to the scattering of r values by conventional method. During the determination of plastic strain ratio by regression method, the strain error could be removed by regression method and the degree of planar anisotropy Δr is proportional to earing ratio.