Solidification behavior of Re-and Ru-containing Ni-based single-crystal superalloys with thermal and metallographic analysis  

作　　者：Gang Liu Lin Liu Zhen-Hua Han Guo-Jun Zhang Jun Zhang 

机构地区：[1]School of Materials Science and Engineering, Xi'an University of Technology, Xi'an 710048, China [2]State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi'an 710072, China

出　　处：《Rare Metals》2017年第10期792-798,共7页稀有金属（英文版）

基　　金：financially supported by the National High Technology Research and Development Program of China (No. 2012AA03A511);the National Natural Science Foundation of China (Nos. 51171151 and 51331005);the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University (No. SKLSP201310);the Science and Technology Program of Shaanxi Province(No.2013JQ6003);the Research Foundation of Education Bureau of Shaanxi Province (No. 2013JK0898)

摘　　要：To clarify the solidification behavior of Re- and Ru-containing Ni-based single-crystal superalloys, four experimental alloys with varied contents of Re and Ru were investigated by differential scanning calorimetry （DSC） and metallographic techniques. To obtain the - solvus temperatures, the stepwise solution and aging heat treatments were used. DSC analysis shows that Re leads to the increase in freezing range and γ-solvus temperature. On the contrast, Ru only has negligible influence on the freezing range, but leads to the lower γ-solvus temperature. In comparison with Ru, Re leads to more severe segregation and higher eutectic fractions in as-cast microstructures. Furthermore, the castability and phase stability of Ni-based superalloys were analyzed by the results of DSC and metallographic analysis, such as freezing range, critical nucleation temperature, γ-solvus temperature and eutectic fractions. It shows that Re leads to the wider freezing range and lower critical nucleation temperature, indicating the worse castability of Re-con- taining Ni-based single-crystal superalloys.To clarify the solidification behavior of Re- and Ru-containing Ni-based single-crystal superalloys, four experimental alloys with varied contents of Re and Ru were investigated by differential scanning calorimetry （DSC） and metallographic techniques. To obtain the - solvus temperatures, the stepwise solution and aging heat treatments were used. DSC analysis shows that Re leads to the increase in freezing range and γ-solvus temperature. On the contrast, Ru only has negligible influence on the freezing range, but leads to the lower γ-solvus temperature. In comparison with Ru, Re leads to more severe segregation and higher eutectic fractions in as-cast microstructures. Furthermore, the castability and phase stability of Ni-based superalloys were analyzed by the results of DSC and metallographic analysis, such as freezing range, critical nucleation temperature, γ-solvus temperature and eutectic fractions. It shows that Re leads to the wider freezing range and lower critical nucleation temperature, indicating the worse castability of Re-con- taining Ni-based single-crystal superalloys.

关 键 词：Ni-based single-crystal alloys Solidification behavior METALLOGRAPHY Thermal analysis 

分 类 号：TG132.3[一般工业技术—材料科学与工程]