新颖裂纹长度测试技术——裂纹扩展片的研制和应用

本文简要介绍了80年代初新开始在金属疲劳裂纹扩展试验中应用的裂纹片测试技术并对近年来开展的研究工作作了综合性的报道。目前已研制成功测量长度为10mm的标准型裂纹片和5mm的可测孔边短裂纹扩展的裂纹片,并研制了定型的智能化配套仪器。从性能测试和实际试件上的试验表明,这两种裂纹片在很大的测量范围内均能保持良好的线性及输出的稳定性,且能很好地跟随试件裂纹的扩展而扩展。文中还对测量中可能出现的问题提出了看法和修正方案,以使这种方法具有更大的精确度。

This paper discribs briefly our research work concerned with the Krak-gage method for monitoring fatigue crack growth rate.including design, property measuring and application. We have designed and fabricated two kinds of bondable Krak-gages, the standard 10mm scale size and 5mm scale size special for short crack measure testing in the hole region. The corresponding instrument controlled by microcomputer is developed for these gages .It can display and record automatically the crack length as well as the cycle number during fatigue testing. Some effective factors are also discussed and the correctional ways are suggested in the paper.