Effect of Different solidification rate on the high-temperature behavior of PWA1422 Nibased superalloy

• Main Authors: Guan-Da Chen, 陳冠達
• Other Authors: Sheng-Rui Jian
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/699r8j

碩士 === 義守大學 === 材料科學與工程學系 === 105 === In this study, MAR-M200 + Hf nickel-based superalloy was used Polycrystalline and superalloy with withdraw rate of DS 60mm/hr、120mm/hr、180mm/hr.Standard heat treatment procedures are solution treatment at 1200 ℃ for 4hr / ArC, the first aging at 1100 ℃ for 4hr /ArC and followed by second aging at 900 ℃ for 32hr /ArC，Mechanical behavior experiments were high temperature creep test at 982℃/207MPa. The microstructure was observed by Hardness Test and Scanning Electron Microscopy (SEM). The experimental results show that the same heat treatment conditions, the withdraw rate of DS 60mm/hr the high temperature mutation (982 ° C / 207MPa) is the best, from the SEM analysis because the pull-down rate of 60mm / hr bar cooling speed is slow The shape grows slowly into the shape of dendrite, and the γ''phase exhibits heterogeneity. The number of MC type carbides and γ / γ''eutectic phase is large and widely distributed, which makes the most sublimable mechanical properties better.