新型Ni_(3)Al基单晶高温合金的显微组织和拉伸性能  

Microstructure and Tensile Properties of New Ni_(3)Al Based Single Crystal Superalloy

作　　者：赵乐 刘丽荣[1] 田素贵[1] ZHAO Le;LIU Lirong;TIAN Sugui(School of Materials Science and Engineering,Shenyang University of Technology,Shenyang 110870,China)

机构地区：[1]沈阳工业大学材料科学与工程学院,沈阳110870

出　　处：《机械工程材料》2022年第11期33-37,共5页Materials For Mechanical Engineering

基　　金：辽宁省自然科学基金资助项目(2020-MS-212)。

摘　　要：采用液态金属冷却(LMC)法制备了新型Ni_(3)Al基单晶高温合金并进行1 290℃×4 h固溶处理和1 000℃×4 h时效处理,研究了合金的显微组织与不同温度(23~900℃)下的拉伸性能。结果表明:经固溶与时效处理后,试验合金组织中的γ′相呈规则的立方体形状,平均尺寸约为0.55μm,体积分数约为72%;合金的抗拉强度与屈服强度随着温度升高先增大后减小,且均在800℃时达到峰值,分别为856,808 MPa;合金断后伸长率的变化规律与强度相反,在800℃达到最小值11%;在600℃及以下温度拉伸时合金的断裂模式为纯剪切型断裂,在760℃拉伸时为纯剪切断裂与微孔聚集型共存的混合型断裂,当拉伸温度在800~900℃范围内时为微孔聚集型断裂。A new Ni_(3)Al based single crystal superalloy was prepared by liquid metal cooling(LMC) method and treated by 1 290 ℃×4 h solid solution and 1 000 ℃×4 h aging. The microstructure and tensile properties at different temperatures(23-900 ℃) of the alloy were studied. The results show that the γ′ phase in the test alloy structure showed a regular cube shape after solid solution and aging treatment, whose average size was about 0.55 μm and volume fraction was about 72%. The tensile strength and yield strength of the alloy increased first and then decreased with increasing temperature, reaching the peak values at 800 ℃, which was 856 MPa and 808 MPa, respectively. The change of elongation after fracture with temperature was opposite to that of strength;the elongation after fracture reached a minimum value of 11% at 800 ℃. The fracture mode of the alloy was pure shear fracture when stretched at 600 ℃ and below. When stretched at 760 ℃, the alloy had a mixed fracture of pure shear fracture and microporous aggregation. When the tensile temperature was between 800-900 ℃, the alloy fractured in a microporous aggregation fracture mode.

关 键 词：Ni_(3)Al基高温合金 显微组织 拉伸性能 屈服行为 

分 类 号：TG146.15[一般工业技术—材料科学与工程]