Effect of Hf and Zr Contents on Stress-rupture and Fatigue Crack Growth Rate Performances in FGH96PM Superalloy

作     者：Tian XIA Yi-wen ZHANG Yue CHI 

作者机构：High Temperature Materials Research InstituteCentral Iron and Steel Research Institute Beijing Key Laboratory of Advanced High Temperature Materials 

出 版 物：《Journal of Iron and Steel Research International》 (国际钢铁研究杂志)

年 卷 期：2014年第21卷第3期

页      面：382-388页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Sponsored by National Basic Research Program of China(2010CB631204) 

主　　题：PM superalloy FGH96 HI Zr stress rupture carbide oxide 

摘      要：Four experimental FGH96 alloys with various contents of Hf and Zr （0 and 0.04%, 0.3% and 0.04%, 0.6% and 0. 04%, 0. 3% and 0.06%, respectively） were produced using PREP （plasma rotating electrode process）＋ HIP （hot isostatic pressing） route. The unnotched and notched stress-rupture properties and fatigue crack growth rate （FCGR） of all the experimental alloys were investigated to study the effect of Hf and Zr. Relevant fracture morphol ogy and microstructure were observed by scanning electron microscopy and transmission electron microscopy. The results revealed that appropriate content of Hf could lengthen stress-rupture life, eliminate notch sensitivity and slo wer FCGR. Microstructure analysis showed that the amount of ＂f phase should be increased or decreased by adjusting Hf and Zr contents, and MC carbide and oxide coupled growth should be increased by adding Hf content, which caused oxycarbide to precipitate along grain boundary and strengthen the alloy. It was found that excessive Zr in Hf- containing FGH96 alloy had certain deleterious effects on stress-rupture property because there was strong Zr segre- gation at prior particle boundary, leaving a long chain of large-size oxides along the boundary. The optimal content of Hf and Zr in FGH96 alloy was 0.6% and 0. 04%, respectively.