材料局部力学性能测试方法

采用穿孔剪切试验和有限元模拟相结合的方法对材料的局部性能进行研究，通过将修正模拟阻力曲线与试验数据相匹配，在模拟分析中利用迭代修正的方法反向推导出材料的本构关系。由此提出利用穿孔剪切试验间接获得材料拉伸力学性能的基本方法。研究中以典型的车用铝合金材料(5052H34和6063T5)及紫铜作为测试对象，对该材料表征方法的精确性进行验证。分析表明，穿孔剪切试验结合有限元反求迭代技术获得材料拉伸应力－应变曲线关系与拉伸试验数据对比最大误差不超过5%，结果较为准确。该方法适用于微区或局部材料的力学性能表征，可为后续接头梯度力学性能研究提供参考。

METHOD IN TESTING OF MECHANICS PERFORMANCE OF MATERIALS LOCAL MECHANICAL BEHAVIOR

Local mechanical behavior of materials was analyzed by means of punch-shearing test combined with a revised finite element simulation algorithm. For the numerical model, a special revised iterative process was put forward to work out the strain-stress curves for an unknown material by matching the simulated reaction force curves with those of test results. Therefore, an indirect method for material characterization was presented based on the punch-shearing test. In addition, the process accuracy was validated by using aluminium alloy 5052H34 and 6063T5 for automobile and red copper as test materials. The results show that maximum error between indirect and direct way is less than 5%, which can be accepted on the whole. This indirect material characterization method can be used for local or micro-zone material modeling, which will be a useful tool for material characterization of inhomogeneous welded joints.