研究了18CrNi4A平板试样在不同拉伸载荷水平下磁记忆信号的变化规律，探讨磁记忆信号及其梯度的绝对值k与应力水平、应力集中程度间的定量关系。结果表明，利用各加载载荷下磁记忆信号减去未加载时磁记忆信号后的曲线过零点，以及Hp(y)曲线梯度的kmax位置，均可对试件应力集中位置进行有效判定，且梯度k与应力大小呈阶梯增长关系；在检测路径上，信号呈线性关系，随着拉伸应力的变大，直线的斜率在损伤各阶段呈先缓慢增加随后指数增长直至屈服，随后曲线斜率下降，直到断裂后磁信号发生激变规律性变化。

The metal magnetic memory signal change of 18CrNi4A was studied under different tensile loads, and the quantitative relationship between magnetic memory signal and stress was investigated. The results showed that stress concentration locations could be predicated effectively according to the zero point of the curve obtained by the magnetic memory signal under loads minus the one under no load and the position of the max slope of the Hp(y) curve. The slope of the Hp(y) curve increases with the increase of stress. There was a linear relationship between the distance from the inspection point and the metal magnetic memory signal. With the increase of the tensile strength, the slope of the metal magnetic memory curve signal increased slowly at the early stage, and then increased rapidly. However, the slope of the curve began to decline after yielding, and the signal dramatically changed when the fracture happens.