结构不连续处应力与磁记忆检测信号的量化关系

Quantitative Relationship of Stress with Metal Magnetic Memory Testing Signal on Discontinuous Structure

磁记忆检测技术被广泛用来定性识别铁磁性构件中的应力集中区,但由于受结构不连续处漏磁场的影响,磁记忆检测信号与应力的定量关系仍需研究。通过制作结构不连续铁磁性材料试样,对其施加不同程度的弹性应力,再对不同应力作用后试样的剩磁场进行了检测,比对了应力和磁记忆检测信号特征参数的定量关系,明确了应力对磁记忆检测信号的量化作用。

In engineering,stress concentration is the major factor leading to the discontinuities and destruction of the structure at a very low load.Meanwhile,the discontinuity of structure in turn easily leads to the gathering of stress concentration,accelerates the expansion of the scope of structural discontinuity and destruction.Thus,identification of stress on the discontinuous structure is essential to ensure the security of the structure.Magnetic memory testing technology is widely used to qualitatively identify the stress concentration zone in ferromagnetic structure.But owing to the leakage of the magnetic field in the discontinuous structure,the quantitative relationship between stress and magnetic memory testing signal has not yet been clear.Based on the above background,a ferromagnetic material specimen with discontinuous structure was made in the present study.Varying degrees of tensile elastic stress were applied into the specimen,and corresponding residual magnetic field signals of specimen were tested.Finally,the quantitative relationship between stress and the magnetic memory signal is compared.The quantitative effect of stress on magnetic memory signal is thus becomes clear.