摘要
在生产45钢活塞杆时发现,经表面感应加热淬火的活塞杆在磨削加工时表面产生微裂纹。成分和组织分析表明,活塞杆所用钢材符合45钢化学成分要求,由于缺少必要的锻造和调质处理,其原始组织保留了大量的粗大网状铁素体,不满足后续表面强化对心部组织的要求。因活塞杆感应加热淬火操作不当,硬化层出现软带,使有效硬化层深度及表面硬度波动范围大大超过技术要求。活塞杆表面磨削不当又诱发拉应力,残存的铁素体被直接撕裂形成表面裂纹。
During manufacturing 45 steel piston rod,it was found that cracks were produced on the induction hardened surface after grinding.The chemical composition and microstructure analysis show that the chemical composition of piston rod meet the requirements of 45 steel,but the original microstructure contains bulky ferrite network and not fit the followed surface hardening specification because of absenting proper forging and quenching and tempering.The fluctuation of effective depth and surface hardness profile exceeded the standard range greatly because there were under-heating structures and soft band in the hardened layer which due to the improper induction quenching.The cracking was promoted by improper grinding stress which would tear remained ferrite directly.
出处
《金属热处理》
CAS
CSCD
北大核心
2011年第2期119-121,共3页
Heat Treatment of Metals
基金
福建省科技重大专项(2008HZ0002-1)
福建省自然科学基金计划项目(E0810024)
福建省教育厅科技项目(JA09150)
集美大学科研基金(ZQ2007014)
关键词
活塞杆
裂纹
感应淬火
网状铁素体
软带
磨削
piston rod
crack
induction quenching
ferrite network
soft band
grinding
