18CrNiMo7-6齿轮轴纵裂分析  

Analysis of Longitudinal Cracks of 18CrNiMo7-6 for Gear Shaft

作　　者：刘玉芬[1] 程丽杰[1] 冯桂萍[1] 刘金鑫[1] 

机构地区：[1]抚顺特殊钢股份有限公司技术中心,辽宁抚顺113001

出　　处：《物理测试》2012年第6期46-49,共4页Physics Examination and Testing

摘　　要：某厂生产的18CrNiMo7-6齿轮轴,在进行热处理过程中出现开裂,将齿轮轴切开,采用金相、扫描电镜等分析方法对试样断口的裂纹源以及裂纹的扩展、裂纹末端进行了综合分析,查找开裂原因。结果表明裂纹两侧没有氧化脱碳,没有非金属夹杂物聚集,裂纹是淬火裂纹,没有发现导致淬火裂纹的冶金缺陷,裂纹是齿轮轴淬火后没及时回火造成的。Gear shaft of 18CrNiMo7-6 steel in some plants happen to crack in the heat-treatment process; the gear shaft was cut, aiming to find out the cracks on 18CrNiMo7-6 steel by testing the gear shaft, the crack source on the fracture surface, its propagation and its end using macroscopic inspection, microscopic inspection as well as elec- tronic microscope scanning. There were no oxidation, decarburization and gathering of nonmetallic inclusions along the crack and its two sides; no metallurgical defects that cause cracking were found and the results showed that cracks were quenching cracks, which were mainly caused by tempering non-timely after quenching

关 键 词：裂纹源 淬火裂纹 冶金缺陷 及时回火 

分 类 号：TG156.3[金属学及工艺—热处理]