摘要
在支承辊的断裂源部位取样,运用失效分析手段,结合化学成分数据、物理性能指标、金相高低倍观察和扫描电镜等分析手段,分析了其断裂的过程以及原因。从中发现造成零件置裂的原因很多,但主要是零件心部所受轴向残余拉应力最大的区域内存在着严重碳偏析和氢脆导致其断裂。严重的碳偏析破坏了基体的连续性,形成薄弱环节。此外相关化学成分超标、晶粒粗大也对支承辊的断裂起到了促进作用。
By sampling at the rupture origin position of back up roll, applying the failure analysis means, combining the these analysis means such as chemical composition data, mechanical property target, macroscopic and micro- scopic metallurgical observation and scanning electron microscope etc, its rupture course and reason have been analyzed. There are some many reasons for stationary cracks of parts. But the main reason is that there is serious carbon segregation and hydrogen embrittlement existed in the range of maximum axial residual tensile stress for part center. The serious carbon segregation can disrupt the continuity of basal body and form the bottle neck. Furthermore, the rele- vant exceeded chemical composition and big crystal grain also can have the accelerative function for the rupture of back up roll.
出处
《大型铸锻件》
2008年第5期15-20,共6页
Heavy Casting and Forging
关键词
支承辊
置裂
断裂源
碳偏析
氢脆
back up roll
stationary crack
rupture origin
carbon segregation
hydrogen embrittlement
