应用d－电子合金设计理论发展新型抗热腐蚀单晶镍基高温合金──Ⅲ．性能评价

APPLICATIONS OF d-ELECTRONS ALLOY DESIGN THEORY TO DEVELOPMENT OF HOT CORROSION RESISTANT Ni－BASE SINGLE CRYSTAL SUPERALLOYS Ⅲ. Characterization of Properties

根据ｄ－电子合金理论研究了合金系统Ｎｉ－１６Ｃｒ－９Ａ１－２Ｗ－１Ｍｏ－４Ｃｏ－Ｔｉ－Ｔａ－Ｎｂ（ａｔ．－％）的热腐蚀行为。选择了最佳成分范围内的４种成分进行单晶生长及性能评价。确定了性能匹配最佳的合金成分（ａｔ．－％）为：Ｎｉ－１６Ｃｒ－９Ａ１－２Ｗ－１Ｍｏ－４Ｃｏ－３．１２５Ｔｉ－０．８７５Ｔａ。完成了整个合金设计过程．该合金抗热腐蚀能力达到或超过ＩＮ７３８ＬＣ，使用温度比ＩＮ７３８ＬＣ高７０－９０℃，其持久强度达到ＣＭＳＸ－２的水平，试验证明ｄ－电子合金设计理论可以用于研制开发高性能抗热腐蚀单晶镍基高温合金．

A study of the hot corrosion behaviour of the alloy system Ni－16Cr－9A1－2W－1Mo－4Co－Ti－Ta－Nb (in at. －%) selected by the d－electrons alloy design theory was conducted. At the same time, four experimental compositions were selected in the optimum compositional ranges to characterize the single crystal growth behaviour and properties.Finally, the compositions of an alloy with the desired balance of the comprehensive properties was determined as Ni－16Cr－gA1－2W－1Mo－4Co－3.125Ti－0.875Ta(at. － %). This alloy satisfies the alloy design requirements fairly good, i.c., it shows the hot corrosion resistance at the same or higher level of IN 738 LC, while the service temperature capability 70－90℃ higher than IN 738 LC. The stress rupture strength of this alloy reaches the level of the single crystal alloy CMSX-2 which contains much less Cr content, and is the highest among the current hot corrosion resistant nickel-base superalloys. The results of this study show the effectiveness and feasibility of applications of the d-electrons alloy design concept to the design and development of hot corrosion resistant nickel-base superalloys.ZHANG Jishan, associate professor,(Department of Materials Science and Engineering,Univeristy of Science and Technology Beijing, Beijing 100083)