【摘要】 国内某钢厂38CrMoAl钢在调质过程中出现了裂纹，对裂纹处进行取样，通过化学成分、宏观检测、显微组织分析、扫描电镜分析等探索裂纹产生的原因。结果表明，该钢裂纹性质为淬火裂纹，其产生的主要原因是原始材料圆坯存在冶金缺陷(缩松、点状偏析等),而调质过程中在组织应力和热应力作用下促进了裂纹的扩展。更多还原

【Abstract】 Cracks occurred after quenching and tempering in 38CrMoAl steel bar produced in a domestic steel mill, the crack was sampled, and the cause of cracks was investigated by means of chemical composition, macroscopic detection, microstructure analysis, scanning electron microscopy analysis, etc. The results show that the cracks are induced during quenching. The main reason for this is the presence of metallurgical defects including shrinkage, spot segregation, etc. in the original material round billet, while the effect of structural stress and thermal stress during the quenching and tempering promotes the propagation of the crack.更多还原