热处理工艺对铸造高温合金K480组织的影响

采用光学显微镜、扫描电镜对K480镍基高温合金的铸态组织和不同固溶、时效处理后的组织进行了观察。研究了不同固溶和时效处理对K480合金组织行为的影响。结果表明,合金经过1130℃亚固溶处理后,组织为大小两种尺寸的γ’相;经过1190、1210和1230℃过固溶处理后空冷,析出均匀的γ’相,并且随着固溶温度的升高,碳化物和共晶的含量逐渐降低。一次时效处理,固溶态γ’相平均尺寸随时效温度升高而增大,合金经1050、1090和1110℃×4 h时效后,γ基体通道中均有更细小的三次γ’相析出,而在之后的二次时效和全时效过程中,这些细小的三次γ’相又重新溶解到基体或周围的大尺寸γ’相中。

Effect of heat treatment process on microstructure of cast superalloy K480

Microstructure of nickel-base superalloy K480 after different heat treatment was studied by OM and SEM.The results show that the γ′ particles is not dissolve completely in the matrix after solution heat treatment at 1130 ℃.Secondary γ′ particles are precipitated uniformly after solution heat treatment at 1190,1210 and 1230 ℃ and the volume of γ/γ′ eutectic and carbides decreases with the increase of solution temperature.Primary aging causes growth of the secondary γ′ particles with the aging temperature increasing.The tertiary γ′ particles appear in the γ matrix channel after aging at 1050,1090 and 1110 ℃ for 4 h.These fine tertiary γ′ particles are re-dissolved into the matrix and larger γ′ particles during the subsequently secondary agine and full time aging.