大型锻件内部云片状夹杂性裂纹产生过程模拟研究

Modelling Study on Crack Occurrence from Cloud-Slice Shape Inclusions inside Heavy Forgings

针对我国生产饼类锻件、模块、筒体等大型锻件时 ,报废锻件内部呈现云片状夹杂性裂纹的质量问题 ,采用物理模拟方法研究饼类锻件内部夹杂性裂纹的产生及云片状缺陷的形成过程。实验表明 :饼类锻件内部云片状缺陷形成于镦粗过程 ,锻造工艺的特殊性是形成缺陷的外因 ,材料特性是产生缺陷的内因 ,并据此提出了相应的改进措施。本文的研究成果对提高大型锻件的内部质量 ,降低废品率 ,具有重要的理论意义和实用价值。

It has been a critical problem that crack originated from cloud-slice shape inclusions occurred inside waste heavy forgings,e.g., heavy disc,die block,tube body,etc.The occurrence of this kind of cracks and formation of cloud-slice defects were investigated by physical simulation.The experimental results show that (1)the defects form in upsetting processes,(2)it were the external causes for some special forging processes to produce the defect ,while the internal causes for some special properties of material,and (3) some measures to improve product quality were put forward.The results of the study are important and useful in production.