ABSTRACT The timely detection of crack defects considerably helps prevent accidents caused by metal component failure. Further, magnetic memory detection technology has the advantage of detecting damage earlier than traditional nondestructive testing technology; however, the relationship between magnetic memory fields and welding cracks needs to be studied. Specimens with buried welding cracks were fabricated to study the magnetic memory field parameters of the propagation process of welding cracks. Variations in the magnetic memory signals of the crack at different loading stages were characterized. The magnetic memory detection method can effectively detect the buried welding crack defects. The magnetic field intensity gradient (dH/dx) demonstrated a regular change with the increase in the applied tensile load (P), which can be considered in two stages: In the first stage (P < 120 kN), dH/dx gradually decreased with P, and in the second stage (P > 120 kN), it rapidly increased before fracture.

中文翻译：

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荷载作用下埋藏裂纹扩展的磁记忆信号研究

摘要 裂纹缺陷的及时检测大大有助于防止由金属部件故障引起的事故。此外，磁记忆检测技术具有比传统无损检测技术更早发现损坏的优势；然而，需要研究磁记忆场和焊接裂纹之间的关系。为了研究焊接裂纹扩展过程的磁记忆场参数，制作了埋入焊接裂纹的试样。表征了裂纹在不同加载阶段的磁记忆信号的变化。磁记忆检测方法可以有效检测埋焊裂纹缺陷。磁场强度梯度 (dH/dx) 表现出随着施加的拉伸载荷 (P) 的增加而有规律的变化，