Cause and analysis of surface crack on the tube billet 36Mn2V
LIU Chao- qun1,LIANG Yan2,WU Di1,LIU Li1,ZHANG Ying- qiu1
（1. Special Steel Division, Laiwu Iron and Steel Group Co., Ltd., Laiwu 271105, Shandong, China 2. Heavy Plate Plant Business Unit, Laiwu Iron and Steel Group Co., Ltd., Laiwu 271105, Shandong, China）
Abstract：The tube billet 36Mn2V is usually used to produce the oil well pipe, which is the important equipment for oil drilling. However, this steel belongs to one of cracking sensitive steel grades, and the surface crack easily occurs. The surface crack defects of rolled product were investigated by metallographic structure and scanning electron microscope analysis. It was found that the obvious decarburized layer, inclusions and oxide dots were observed near the structure of crack. Moreover, many ferrite bands existed at the end of the crack. The results indicated that the quality defect of the casting billet was the main reason to cause the surface crack on the billet 36Mn2V.
刘超群，梁艳，武迪，刘利，张迎秋. 36Mn2V管坯钢表面裂纹形态分析及成因探讨[J]. 中国冶金, 2015, 25(11): 56-60.
LIU Chao- qun,LIANG Yan,WU Di,LIU Li,ZHANG Ying- qiu. Cause and analysis of surface crack on the tube billet 36Mn2V. China Metallurgy, 2015, 25(11): 56-60.
2015, Vol. 25 
