为研究汽车驱动桥壳再制造的金属磁记忆检测,选用510L钢拉伸试样,分析了塑性应变不同阶段磁记忆信号的变化规律;以材料拉伸试验为基础,针对废旧驱动桥壳进行磁记忆损伤检测及变形量检测,得到了桥壳变形量与磁记忆信号特征值的关系。结果表明,随着应变量的增大,拉伸试样表面磁记忆信号法向分量Hp(y)由斜线、无异变峰变化为反转且出现过零点,磁记忆信号法向分量梯度Kmax早期缓慢增大,颈缩时出现快速增大;桥壳的变形检测显示,桥壳变形量与Kmax存在量化关系,当桥壳发生较大变形时,梯度Kmax发生突变,磁记忆检测可为再制造损伤评估提供依据。
In order to study the magnetic memory NDT for remanufacturing of drive axle housing, pieces of smooth stretch material with 510L were selected to analyze the change of magnetic signals at the different stages of plastic strain. Based on the tensile tests of 510L, the magnetic memory testing and detection of deformation for the drive axle housing were performed. The relationship between the deformation and the magnetic memory signals was established. The results show that magnetic mem- ory normal component Hp (y) changes from the slash without the mutation peak into reversal with the zero crossing; when increasing strain of tensile specimen, the magnetic memory normal component gradient Kma. slowly increases in the early stage, and rapid increases when specimen appearing neck- ing. The quantitative relationship between axle housing deformation and Kmax can be established, and the gradient Kmax appears the mutation when axle housing gets a larger deformation. Magnetic memo- ry testing can provide the basis for damage assessment of parts to be remanufactured.