CAJ | 학술논문

对45#钢圆环套筒类支座零件进行调质处理时,发生多个零件圆环内壁出现裂纹.采用ICP光谱仪、光学金相显微镜及宏观特征等手段对裂纹特征进行分析.结果表明:该批零件因热处理淬火前锻造工艺控制不当,锻造温度高,达到该材料的过热、过烧温度,造成显微组织中非金属夹杂物沿晶界分布及混晶、晶粒粗大等缺陷,弱化了晶界,降低材料的强度和韧性;淬火过程中由于热处理残余应力的变化,在几何尺寸小、形变空间也小的内壁形成沿晶扩展的淬火裂纹.
대45#강원배투통류지좌령건진행조질처리시,발생다개령건원배내벽출현렬문.채용ICP광보의、광학금상현미경급굉관특정등수단대렬문특정진행분석.결과표명:해비령건인열처리쉬화전단조공예공제불당,단조온도고,체도해재료적과열、과소온도,조성현미조직중비금속협잡물연정계분포급혼정、정립조대등결함,약화료정계,강저재료적강도화인성;쉬화과정중유우열처리잔여응력적변화,재궤하척촌소、형변공간야소적내벽형성연정확전적쉬화렬문.
Cracks appeared on the inner wall of ring during thermal refining of 45# steel ring sleeve bearing parts. By using ICP spectrometer and optical microscope,crack characteristics were analyzed. The results indicate that there exists some non?metallic inclusions along crystal boundary,some defects of mixed crystal,coarse grain and so on,because the forging process is not well controlled before quenching,which leads to high forging temperature,reaching superheating and overheating temperature of material. These defects weaken grain boundary,reduce strength and toughness of the material. Due to the variation of residual stress during heat treatment quenching process,some quenching cracks along crystal boundary appear on the inner wall.