摘要
某装载机用油缸的缸筒材料为正火后的45钢,在正常试压实验时,缸筒突然发生破裂。利用宏观和微观检验、化学成分分析和硬度测试等方法对油缸外筒破裂的原因进行了分析。结果表明,在焊接热影响区局部区域出现马氏体组织,而且基体组织不均匀,近表层晶粒粗大,易产生更加粗大的马氏体组织,使焊接接头局部区域脆性增加,从而在易产生应力集中的转角部位,发生沿纵向的瞬时破断。
The 45 steel after normalizing for hydraulic oil cylinder material of loader was cracked during a pressure test. Macroscopic and microscopic examinations, chemical composition analysis and hardness test were carried out on the cracked cylinder. The results show that mar- tensite appeared in the heat-affected zone, and more coarse grains near the surface were easy to produce more coarse martensite, leading to increased fragility in the local area of welded joints. At the corner, crack occurred in the longitudinal direction under large stress concentration.
出处
《上海电机学院学报》
2015年第5期255-259,共5页
Journal of Shanghai Dianji University
基金
上海市教育委员会科研创新项目资助(14YZ159)
上海高校青年教师培养项目资助(ZZSDJ12006)
上海电机学院登峰学科建设项目资助(15DFXK02)
上海电机学院重点培育项目资助(12C112)
上海电机学院教师科研启动经费项目资助(13C417)
关键词
液压油缸缸筒
破裂
组织
硬度
应力集中
hydraulic oil cylinder
crack
structure
hardness
stress concentration
