摩托车排气管断裂失效的研究  

RESEARCH OF MOTORCYCLE EXHAUST PIPE FRACTURE FAILURE

作　　者：王正进 

机构地区：[1]新大洲本田摩托有限公司,上海201708

出　　处：《机械强度》2015年第6期1159-1162,共4页Journal of Mechanical Strength

摘　　要：对摩托车消声器排气管断裂件进行了断口形貌和金相分析。评定热影响区平均晶粒度为3级,母材晶粒度等级为6级。裂纹萌生在焊接的起弧区域,该区域的瞬间过热可能导致晶粒粗大,脆性增加;焊缝中留有夹杂物未清理干净使得局部强度降低,在服役的过程中应力集中引发裂纹萌生。裂纹由里向外逐渐缓慢扩展,到达临界点后排气管发生瞬间断裂。For the motorcycle muffler exhaust pipe rupture fracture morphology and metallographic analysis. Assessment of heat affected zone average grain size of level 3,parent metal grain size grade for level 6. Crack initiation in the region of the welding arc,instantaneous overheat of the region may result in coarse grains,brittleness increases; With inclusions in weld not clean up the local strength is reduced,in the process of serving the stress concentration caused by crack initiation. Crack from the inside to the outside slowly expanding gradually,reached a tipping point instantly exhaust pipe before and after the break.

关 键 词：热影响区 平均晶粒度 疲劳断裂 

分 类 号：TG113.25[金属学及工艺—物理冶金]