试样复用对拉伸强度和被粘物加工硬化的影响

On the effects of specimen recycling to the tensile strength and work hardening

对拉伸试样被粘表层中的加工硬化现象作了分析 ,采用 3种尺寸的钢制试样研究复用次数对拉伸强度的影响。结果表明 ,试样的复用次数对拉伸强度有明显的影响 ,原因在于金属被粘物表层上出现加工硬化或存在残余应力。

The work hardening on the surfaces of cylinder adherends during loading process was analyzed. Three kinds of steel cylinder adherends were used to investigate the effect of sample recycling time on the tensile strength. The results showed that this effect was obvious and the reason is that there exists work hardening in the surface layer or residual stress. The authors also give a group of curve fitting formulae for explain the relation between the sample size and tensile strength under different recycling times.