GH4145合金中γ′相析出对晶界片状M23C6相析出的影响  

Effect of γ′ Precipitation on Lamellar M23C6 Carbide Precipitation in GH4145 Alloy

作　　者：华培涛[1] 陈斯博 张伟红[1] 姚晓雨 孙文儒[1] HUA Peitao;CHEN Sibo;ZHANG Weihong;YAO Xiaoyu;SUN Wenru(Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China;AECC Shenyang Liming Aero-Engine Co.,Ltd.,Shenyang 110000,China)

机构地区：[1]中国科学院金属研究所,沈阳110016 [2]中国航发沈阳黎明航空发动机有限责任公司,沈阳110000

出　　处：《航空制造技术》2020年第3期92-95,102,共5页Aeronautical Manufacturing Technology

摘　　要：片状M23C6相是GH4145等高温合金中的典型有害组织,尽管过去对其析出机制的研究较多,但其析出条件一直没有明确。研究了不同固溶冷却条件下γ′相的析出规律,以及随后进行的730℃时效过程中晶界M23C6相的析出规律。通过对比分析,发现片状M23C6相的析出与γ′相析出之间存在直接的联系。当980℃固溶后的冷却速率低于4.5℃/h,GH4145合金的γ′相会在冷却过程中析出;冷却速率高于22℃/s时,γ′相的析出会被完全抑制。当GH4145合金的基体中预先析出γ′相时,M23C6相的析出和长大受元素扩散控制,最后将生长成嵌入两侧晶粒的块状。当基体中无γ′相析出时,有可能导致局部晶界发生γ′相与M23C6相的共析反应,形成互相交迭的片状组织。The lamellar M23C6 phase is a typical harmful microstructure formed in the superalloys including GH4145.The mechanism for the precipitation of the lamellar structure has been investigated extensively,the conditions for the precipitation of the lamellar structure of the M23C6 carbide,however,remains unclear till now.By analyzing the precipitation ofγ′and M23C6 phases during the cooling after the 980℃solution and the subsequent 730℃aging,it was found that the lamellar M23C6 precipitation was directly governed by theγ′precipitation.After the 980℃solution,theγ′precipitation could be prohibited thoroughly when the cooling rate is higher than 22℃/s.During the subsequent 730℃aging after the 980℃solution,the M23C6 carbide precipitated as isolated particles when theγ′phase pre-precipitated in the matrix,because theγ′phase would inhibit the directional growth of the carbide.While the M23C6 carbide might grow into lamellar form with theγ′phase by the eutectoid reaction of(M23C6+γ′)when there was no theγ′precipitates in the matrix before the aging.The coprecipitation of M23C6 andγ′is the necessary conditions for the formation of the lamellar M23C6 carbide.

关 键 词：镍基高温合金 GH4145合金 M23C6相 片状组织 

分 类 号：TG132.3[一般工业技术—材料科学与工程]