增材制造单晶镍基高温合金微观组织、热稳定性及耐磨性能
Microstructure,thermal stability and wear resistance of additively manufactured single crystal Ni-based superalloys
任晨宇 1林思聪 1陈凯 1张丹利 1周光妮 2梁晓晴 2罗思海 2何卫锋2
作者信息
- 1. 西安交通大学 金属材料强度国家重点实验室,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,西安 710038
- 折叠
摘要
利用定向能量沉积的增材制造方法制备了单晶镍基高温合金SRR99,通过微观组织表征、硬度测量与纳米划痕实验,系统地研究激光增材制造单晶镍基高温合金在服役温度下的组织稳定性.结果表明:经过服役温度(650℃)退火100 h后,增材制造样品γʹ强化相的形貌及尺寸(70 nm)依旧保持.相比于传统铸造样品,服役温度退火前后增材制造样品的硬度(6.6 GPa)均提高了20%以上.此外,退火前后增材制造样品的摩擦因数均具有数值低(0.19)、离散性小的特点.本研究证明定向能量沉积增材制造的单晶镍基高温合金样品拥有优异的组织热稳定性和耐磨性能,为激光增材制造技术应用于单晶镍基高温合金涡轮叶片的榫头修复与提性延寿提供了实验支撑.
Abstract
The single crystal Ni-based superalloy SRR99 was fabricated by laser-directed energy deposition(LDED).Through microstructural characterization,hardness measurements and nanoscratch tests,the microstructural stability of LDED single crystal Ni-based superalloy at the service temperature was systematically investigated.The results show that the morphology and size(70 nm)of the γʹ precipitates in LDED samples remain stable after annealing at the service temperature(650℃)for 100 h.The hardness values of LDED samples keep almost unchanged(6.6 GPa)before and after annealing,and are more than 20%higher than that of the traditional cast samples.Furthermore,the coefficients of friction of the LDED samples before and after annealing are lower(0.19)and less scattering than those of their cast counterparts.This study demonstrates that Ni-based superalloy single crystals fabricated by LDED exhibit excellent thermal stability and friction properties,paving the way to the application of LDED technology in the repair and life extension of single-crystalline turbine blade dovetails.
关键词
激光增材制造/单晶镍基高温合金/耐磨性能/热稳定性/纳米划痕Key words
laser additive manufacturing/single crystal Ni-based superalloy/wear resistance/thermal stability/nanoscratch testing引用本文复制引用
基金项目
国家重点研发计划资助项目(2023YFB3712002)
国家自然科学基金资助项目(51927801)
国家自然科学基金资助项目(U2032205)
出版年
2024
NETL
NSTL
万方数据