GH4065A镍基高温合金多道次压缩变形组织演变规律  

Microstructure evolution laws of multi-pass compression deformation for nickel-base superalloy GH4065A

作　　者：税烺 付建辉 赖宇 Shui Lang;Fu Jianhui;Lai Yu(Department of Special Steel Technology,Chengdu Institute of Advanced Metallic Material Technology and Industry Co.,Ltd.,Chengdu 610300,China;State Key Laboratory of Metal Material for Marine Equipment and Application,Anshan 114009,China)

机构地区：[1]成都先进金属材料产业技术研究院股份有限公司特钢技术研究所,四川成都610300 [2]海洋装备用金属材料及其应用国家重点实验室,辽宁鞍山114009

出　　处：《锻压技术》2023年第3期244-254,共11页Forging & Stamping Technology

摘　　要：使用不同应变速率、不同应变量的阶段式降温工艺对GH4065A镍基高温合金在多道次压缩变形过程中的组织演变进行研究。结果显示:通过两道次各50%的压缩量即累积75%的工程应变量可以获得与相同温度、相同应变速率下单道次70%工程应变量接近的完全再结晶且晶粒细小的组织,即累积真应变达到1.39以上。每道次低于50%的工程应变量易产生未完全再结晶的“项链组织”或导致晶粒粗大。通过Deform模拟的直径为Φ508 mm的铸锭开坯过程显示,设置的变形工艺可实现在两镦两拔的情况下,使坯料中心部位的累积等效应变达到1.39以上,组织完全再结晶,而两端部分还有部分累积等效应变未能达到1.39,需要第3火次的变形以实现完全再结晶。变形过程中的晶粒粗大问题需要通过调节γ′相的析出来控制。The microstructure evolution of nickel-base superalloy GH4065A during the multi-pass compression deformation process using staged cooling process with different strain rates and different strain amounts was studied.The results show that by accumulating the engineering strain amount of 75%in two passes with each compression amount of 50%,a fully recrystallized and fine-grained structure close to the 70%engineering strain amount in a single pass under the same temperature range and the same strain rate can be obtained,that is,the accumulated true strain reaches above 1.39.A engineering strain amount of lower than 50%in each pass is likely to cause incompletely crystallized“necklace structure”or coarse grains.The cogging process of cast with the diameter ofΦ508 mm simulated by Deform shows that the set deformation process is able to allow the central part of billet to reach the accumulated more than the equivalent strain of 1.39 and to reach complete recrystallization by two-time upsetting and two-time pulling,whereas two ends are still partially failed to reach the accumulated equivalent strain of 1.39,requiring the third deformation to achieve complete recrystallization.And,the problem of coarse grains during deformation needs to be controlled by adjusting the precipitation ofγ′phase.

关 键 词：镍基高温合金 多道次变形 开坯工艺 晶粒粗大 完全再结晶 

分 类 号：TG316[金属学及工艺—金属压力加工]