单晶镍基高温合金增材修复的定制化热处理  

Custom-Designed Heat Treatment for 3D-Printed Single-Crystal Ni-Based Superalloys

作　　者：林弈安 王兆伟 何卫锋[2] 罗思海[2] 陈凯 LIN Yian;WANG Zhaowei;HE Weifeng;LUO Sihai;CHEN Kai(State Key Laboratory for Mechanical Behavior of Materials,Xi'an Jiaotong University,Xi'an 710049,China;National Key Lab of Aerospace Power System and Plasma Technology,Air Force Engineering University,Xi'an 710038,China)

机构地区：[1]西安交通大学材料科学与工程学院,陕西西安710049 [2]空军工程大学航空动力系统与等离子体技术全国重点实验室,陕西西安710038

出　　处：《中国材料进展》2025年第4期380-386,共7页Materials China

基　　金：国家自然科学基金资助项目(51927801,U2032205,52271042)。

摘　　要：增材制造(3D打印)技术在镍基高温合金单晶叶片的修复领域展现出重要应用前景。该技术具有温度梯度大、冷却速度快等特点,有利于促进枝晶定向生长、实现枝晶组织细化,但是同时也容易产生高残余应力、高位错密度,从而在后续热处理与高温服役过程中引发再结晶、开裂等问题,造成极大的安全隐患。因此,需要对增材修复的镍基高温合金单晶开发定制化热处理研究。高温合金的标准热处理一般由超固相线固溶、时效等步骤组成。以增材修复高温合金单晶特有的微观组织为出发点,提出“筏化-回复”及“亚固相线固溶”策略,有效抑制再结晶及3D打印产生的杂晶晶粒生长,同时有效降低位错密度、释放应力、调控沉淀强化相组织,为实现单晶涡轮叶片的增材修复提供保障。Additive manufacturing(3D printing)is a promising route to repair damaged Ni-based superalloy single crystal blades.This technology is featured by steep temperature gradient and high cooling rate.The characteristics favor the direc-tional growth of dendrites and realise microstructure refinement.However,additive manufacturing process also produce high residual stress and high microstructural defect density,which will trigger disastrous recrystallization and cracking in the sub-sequent heat treatment and/or high temperature service process.Therefore,customized heat treatment is demanded for the 3D-printing repaired Ni-based superalloy single crystals.The standard heat treatment of superalloy generally consists of the steps of super-solvus solution and aging.Considering the unique microstructure of as-printed single crystal superalloys,the strategies of rafting-enabled recovery and sub-solvus solutionizing are demonstrated in this work,which effectively prevent re-crystallization and stray grain growth,reduce dislocation density,release stress,and optimizeγ′morphology and volume fraction.Our study paves the way for the 3D-printing repair of damaged Ni-based superalloy single crystal turbine blades.

关 键 词：镍基单晶高温合金 增材制造 热处理 回复 亚固相线固溶 

分 类 号：TG132.3[一般工业技术—材料科学与工程] TG665[金属学及工艺—合金]