激光直接沉积修复1Cr15Ni4Mo3N钢磁痕分析

针对激光直接沉积修复的1Cr15Ni4Mo3N钢零件在磁粉检测时出现的磁痕现象,采用接触通电、湿磁粉连续法,对设计的试样进行磁粉检测,确定磁痕显示位置;利用光学显微镜对磁痕显示处形貌及修复接头和组织进行观察和研究,分析磁痕的性质和形成原因。研究发现:激光直接沉积修复1Cr15Ni4Mo3N钢在磁粉检测过程中与修复区外轮廓完全重合的磁痕显示是伪磁痕显示,主要是由修复区与基体中奥氏体含量的差异造成的。

Analysis of Magnetic Particle Indication on 1Cr15Ni4Mo3N Steel Repaired Using Laser Direct Metal Deposition Technology

Magnetic particle indication usually occurred on 1Cr15Ni4Mo3N steel components repaired by laser direct metal deposition technology during magnetic particle testing. In order to determine the position of magnetic particle indication, the designed samples were measured by magnetic particle inspection. The morphology of the magnetic traces and microstructure of the repaired joint were observed and studied to analyze the characterization and forming reason of the magnetic traces. The results indicate that the magnetic particle indications, detected on the 1Cr15Ni4Mo3N steel repaired by laser direct metal deposition technology, are completely coincident with the outer outline of the repaired zone. The morphologies of the repaired zones are able to confirm that the magnetic particle indications are pseudo-magnetic traces. The special magnetic particle indication is mainly attributed to the great difference of austenite content between the 1Cr15Ni4Mo3N steel substrate and its repaired zone.