Low-Cycle Fatigue Properties of Nickel-Based Superalloys Processed by High-Gradient Directional Solidification

作     者：Z.D.Fan D.Wang C.Liu G.Zhang J.Shen L.H.Lou J.Zhang 

作者机构：Superalloys DivisionInstitute of Metal ResearchChineseAcademy of SciencesShenyang 110016China Shenyang National Laboratory for Materials ScienceInstitute of Metal ResearchChinese Academy of SciencesShenyang 110016China Xi'an Thermal Power Research Institute Co.Ltd.Xi'an 710054China 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：2017年第30卷第9期

页      面：878-886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：financially supported by the National Natural Science Foundation of China under Grant Nos.51631008 51101160 and 2010CB631201 

主　　题：Superalloys Rapid solidification Low-cycle fatigue Microstructure 

摘      要：The low-cycle fatigue （LCF） properties of DD10 （single-crystal） and DZ53 （columnar-grained） superalloys solidified by liquid-metal cooling （LMC） and high-rate solidification （HRS） processes have been systematically investi- gated. It was found that the LCF life of DZ53 solidified by LMC was obviously better than that solidified by HRS. In contrast, for DD10, LMC showed no remarkable influences on LCF properties at high temperature and only improved LCF properties at intermediate temperature. Microstructure examination showed that the cracks generally initiated at microp- ores in the subsurface at intermediate temperature. However, the cracks occurred on the surface due to oxidation, or persistent slip bands near script-MC at high temperature. Therefore, the benefits of LMC technique can be attributed to both of the reduced casting defects which significantly affect the LCF properties at intermediate temperature and the improved microstructural homogeneity which was strongly correlated to the LCF properties of alloys at high temperature.