Mechanical properties in cyclic tension-compression loading process on sheet metal

摘要

In the process of reciprocating bending, any particle of the workpiece is subjected to cyclic tensile compression deformation. The workpiece undergoes a reciprocating bending deformation process, and each particle undergoes a cyclic tension-compression loading cycle. In this paper, cyclic tensile loading tests under different prestrains and strain amplitudes are carried out. The macroscopic behavior of 304 stainless steel and ST12 cold rolled plate under cyclic tension-compression loading and the effect of prestrain on the stable hysteresis loop of the two materials are studied. Thus, the evolution of macroscopic mechanical properties in the process of reciprocating bending deformation is deeply understood. The experimental results show that 304 stainless steel and ST12 cold rolled plate are characterized by cyclic softening; the prestrain has little effect on the stable hysteresis loop, the cyclic tension-compression loading eliminates the initial difference of the mechanical properties caused by the prestrain and makes the mechanical properties of materials tend to be uniform. It is also proved indirectly that the reciprocating bending has not only the effect of uniform curvature, but also makes the mechanical properties of the same layer of fibers be homogenized.