摘要
42CrMo钢法兰经860℃淬火和570℃回火后发现表面出现裂纹。通过化学成分分析、显微硬度测定、金相检验和冲击试验等方法分析了法兰开裂的原因。结果表明,裂纹的侧面存在氧化物,说明裂纹是在淬火过程中发生的。改进措施为:采用预冷淬火工艺,用聚合物溶液淬火代替水淬,或适当降低淬火加热温度。
Crack was found in 42CrMo steel flange which has been quenched from 860 ~C in water and tempered at 570 ~C. The flange having crack was subjected to composition analysis, microhardness measurements, metallographic examination, and impact tests to reveal the reason why the crack develop. The results indicate that oxides are present in the sides of crack, this shows the crack forms during the quenching of flange. The flange may be prevented from cracking by the use of delay quenching, quenching in polymer solution instead of water, or appropriate reduction in austenitizing temperature.
作者
贺凯林
金丽萍
HE Kailin JIN Liping(Jiangsu Muyang Co., Ltd., Yangzhou 225127, Jiangsu China)
出处
《热处理》
CAS
2017年第1期52-54,共3页
Heat Treatment
关键词
氧化物
淬火裂纹
碳当量
oxides
quenching crack
carbon equivalent
