34CrMo4钢中空轴开裂原因分析  

Analysis on Cause of 34CrMo4 Steel Hollow Shaft Cracking

作　　者：杨永强 欧阳建国 董立峰[2] 郑春雷[2] YANG Yongqiang;OUY ANG Jianguo;DONG Lifeng;ZHENG Chunlei(Engineering Research Center for Sling of Hebei,Juli Sling Co.,Ltd.,Baoding 072550,Hebei China;Yanshan University,Qinhuangdao 066004,Hebei China)

机构地区：[1]巨力索具股份有限公司河北省吊索具工程技术研究中心,河北保定072550 [2]燕山大学材料学院,河北秦皇岛066004

出　　处：《热处理》2021年第6期52-55,共4页Heat Treatment

基　　金：国家重点研发计划:重载铁路耐磨钢轨钢的组织性能关系及损伤机理研究(2017YFB0304501)。

摘　　要：外径110mm、内径30mm的34CrMo4钢中空轴,870℃水淬和640℃回火后发现有约20mm长的裂纹。为此对开裂的中空轴进行了化学成分分析、力学性能检测、金相检验,检验了裂纹的表面状况,并对夹杂物进行了能谱分析。结果表明:该中空轴的化学成分、力学性能均符合要求,显微组织基本正常,裂纹表面被严重氧化。据此可以断定,34CrMo4钢中空轴开裂是淬火不当所致。此外,含Mn和S的夹杂物也促进了中空轴的淬火开裂。改进淬火方式后,中空轴开裂的问题已经解决。A 110-mm-OD,30-mm-ID hollow shaft of 34CrMo4 hollow shaft was found to have about 20-mm long crauck after quenching fom 870℃ in water followed by tempering at 640℃.For this reason,the cracked hollow shaft was tested for chemical composition,mechanical properties and microstructure,the surface condition of the cmck was checked,and the inclusions were subjected to energy spectrum analysis.The results showed that the hollow shaft exhibited desirable chemical composition and mechanical properties,basically normal microstructure,and severely oxidized crack surface.In view of the above it may be concluded that cracking of the 34CrMo4 steel hollow shaft is caused by fault in its quenching.In addition,the presence of inclusions with manganese and sulphur also contributes to the cracking of hollow shaft during quenching.After the quenching manner being improved,the problem of hollow shaft cracking has been solved.

关 键 词：34CrMo4钢 中空轴 淬火裂纹 夹杂物 

分 类 号：TG115[金属学及工艺—物理冶金]