K418铸造叶轮断裂原因分析  

Fracture Analysis of K418 Cast Impeller

作　　者：张晓义[1] 李崇巍[1] 

机构地区：[1]北京北冶功能材料有限公司,北京100192

出　　处：《金属材料研究》2015年第1期27-32,共6页Research on Metallic Materials

摘　　要：在用K418高温母材合金浇铸叶轮后，对叶轮做拉伸试验时发现在拉伸强度为550MPa时发生断裂，设定的合格标准要求断裂强度大于680MPa。因此，开展了用金相法分析断裂原因的研究。叶轮断裂的主要原因可能是合金在凝固过程中，成分偏析导致析出大量的脆性相，脆性相的析出增加了材料的室温脆性，从而导致叶轮断裂。K418 high-temperature alloy has been widely used such as casting impeller due to its excelleut properties. During tensile test, one specimen breaks when the tensile strength is at 550MPa, which is less than the expected teusile strength with 680MPa. Metal- lurgical analysis shows thas the main reasons for breaking of the impeller may be explained that during solidification, segregation leads to precipitation of a large number of brittle pha- ses, and thus increases precipitation brittle phase brittle materials at room temperature, and thus leads to impeller fracture.

关 键 词：断裂 拉伸强度 成分偏析 脆性相 

分 类 号：TG166[金属学及工艺—热处理]