摘要
针对金属材料在屈服阶段塑性变形比较复杂且难以准确测量的问题,提出一种基于数字图像相关法的光学方法来测量H340LAD__Z高强度钢的塑性演变行为。设置拉伸速度为1 mm/min,试件厚度为1 mm,以平行轧制方向拉伸试件,获取试件全场全过程变形数据;通过分析对比试件在屈服阶段的关键点位移及全场应变云图,获得该试件的塑性变形演化规律及屈服阶段的开始与终了时刻。实验结果表明:试件的演变行为从斜两侧向中间转移,塑性变形不均匀;从颈缩到断裂过程,不同关键点工程应变差异大。因此,该方法对研究金属材料的塑性理论及工业应用具有积极的指导意义。
Aiming at the problem that the plastic deformation of metal material is complex and difficult to be measured accurately in the yield stage, an optical method based on digital image correlation is proposed to measure the plastic evolution of H340LAD__Z high-strength steel. Setting the stretch speed is 1 mm/min, specimen thickness is 1 mm, stretching the specimen in parallel to the rolling direction to obtain the whole-process deformation data of the specimen. By analysing and comparing the key point displacement and the full-field strain cloud chart of the specimen in the yield stage, the evolution law of plastic deformation and the beginning and end time of the yield stage of the specimen are revealed. The test results show that the evolution behaviour of this specimen transfers from both sides to the middle and the plastic deformation is inhomogeneous.From austerity to fracture, the engineering strain of different key points is differont. Therefore,this method has a positive guiding significance for studying the plasticity theory and industrial application of metal materials.
出处
《中国测试》
北大核心
2017年第12期119-123,共5页
China Measurement & Test
基金
国家自然科学基金资助项目(51675404
51421004)
关键词
屈服行为
塑性变形
数字图像相关法
演变规律
yield behavior
plastic deformation
digital image correlation
evolution law
