高端数控机床导轨用灰铸铁感应淬火裂纹成因分析  

Causes analysis of induction hardening cracks in grey cast iron for high-end CNC machine tool guide rails

作　　者：严昊明 于朋翰 于兴福 Yan Haoming;Yu Penghan;Yu Xingfu(General Technology Group Machine Tool Engineering Research Institute Co.,Ltd.,Beijing 100102,China;Shenyang Machine Tool of General Technology,Shenyang Liaoning 110142,China;School of Mechanical Engineering,Shenyang University of Technology,Shenyang Liaoning 110870,China)

机构地区：[1]通用技术集团机床工程研究院有限公司,北京100102 [2]通用技术集团沈阳机床有限责任公司,辽宁沈阳110142 [3]沈阳工业大学机械工程学院,辽宁沈阳110870

出　　处：《金属热处理》2025年第1期282-287,共6页Heat Treatment of Metals

摘　　要：对HT300成形的高端数控机床导轨进行感应淬火,分析了感应淬火对组织、硬度和淬硬层厚度的影响,并对淬火过程中产生裂纹的原因进行了分析。结果表明,HT300铸铁机床一体式导轨经中频感应淬火后,导轨表面硬度可以达到700 HV(60 HRC)以上,淬硬层深度达到5.5 mm。感应淬火热处理后,铸铁导轨表面层主要形成隐晶马氏体,过渡层主要为马氏体+珠光体组织,心部主要为珠光体组织。裂纹分析表明,铸铁中的石墨主要为E型石墨,同时存在的磷共晶组织在淬火过程中发生溶解和析出,降低了铸铁表面强度,大层深感应淬火后表面层形成了拉应力,拉应力超过铸铁强度,是导致铸铁淬火开裂的主要原因。开裂源位于表面,且开裂位置多为磷共晶区域。Effect of induction hardening on the microstructure,hardness,and hardened layer thickness was analyzed of a high-end CNC machine tool guide rail formed by HT300.The causes of cracks during the quenching process were also analyzed.The results show that after intermediate frequency induction hardening,the surface hardness of the machine tool integrated guide rail of cast iron HT300 can reach over 700 HV(60 HRC),and the depth of the harded layer can reach 5.5 mm.After induction hardening heat treatment,the surface layer of the cast iron guide rail mainly forms cryptocrystalline martensite,the transition layer mainly consists of martensite+pearlite structure,and the core is mainly composed of pearlite structure.Crack analysis shows that the graphite in cast iron is mainly E-type graphite,and the phosphorus eutectic structure present in the cast iron dissolves and precipitates during quenching,reducing the surface strength of the cast iron.After deep layer induction hardening,the tensile stress formed on the surface layer exceeds the strength of the cast iron,which is the main reason for the cracking of the cast iron during quenching.The cracking source is located on the surface,and the cracking location is mostly in the phosphorus eutectic region.

关 键 词：机床导轨 感应淬火 HT300铸铁 磷共晶 微观组织 

分 类 号：TG143.2[一般工业技术—材料科学与工程]