喷丸对DD412单晶高温合金表面完整性和疲劳性能的影响
Effects of shot peening on surface integrity and fatigue properties of DD412 single crystal superalloy
王琨 1罗学昆 1宋尽霞 2周春根 3田凯 1王一鸣 1王欣1
作者信息
- 1. 中国航发北京航空材料研究院 表面工程研究所,北京 100095;中国航发北京航空材料研究院 航空材料先进腐蚀与防护航空重点实验室,北京 100095
- 2. 中国航发北京航空材料研究院先进高温结构材料重点实验室,北京 100095
- 3. 北京航空航天大学 材料科学与工程学院,北京 100191
- 折叠
摘要
为提高涡轮叶片榫头的疲劳性能,研究了喷丸对DD412单晶合金表面完整性和高温疲劳性能的影响规律.采用白光干涉仪、粗糙度仪、显微硬度计、扫描电镜、透射电镜等分别对喷丸前后的表面形貌、粗糙度、硬度梯度、微观组织进行表征,并采用旋弯疲劳试验机测试高温疲劳寿命和极限.结果表明:喷丸后,表面磨削刀痕被消除,显著降低表面微观应力集中系数;试样表层组织发生剧烈塑性变形,并形成深度约0.10～0.32 mm的硬化层.相比未喷丸试样,优化工艺喷丸试样在600℃/500 MPa条件下的旋弯中值疲劳寿命提高21.7倍以上,在600℃下的中值疲劳极限提高了17.3%.经分析认为,喷丸对表面完整性的优化是DD412合金高温疲劳性能提升的主要原因.
Abstract
To improve the fatigue performance of turbine blade tenon,the effect of shot peening on the surface integrity and high temperature fatigue performance of DD412 single crystal alloy was investigated.The surface morphology,roughness,hardness gradient and microstructure after shot peening were characterized by white light interferometer,roughness tester,microhardness tester,scanning electron microscope and transmission electron microscope respectively.The results show that after shot peening,the surface grinding tool marks are eliminated,and the surface micro stress concentration factor is significantly reduced.Severe plastic deformation occurr in the surface layer of the specimen,and a hardened layer with a depth of about 0.10-0.32 mm is formed.The mean fatigue life of the optimal shot peening specimens at 600℃/500 MPa is increased by more than 21.7 times,and the median fatigue limit at 600℃is increased by 17.3%.The favorable change of surface integrity is the main reason for the improvement of high temperature fatigue properties of DD412 alloy after shot peening.
关键词
喷丸/单晶合金/表面完整性/疲劳寿命/微观组织/硬度Key words
shot peening/single crystal alloy/surface integrity/fatigue life/microstructure/hardness引用本文复制引用
基金项目
国家自然科学基金(52271076)
国家科技重大专项(Y2022-Ⅶ-0007-0094)
国家科技重大专项(J2019-Ⅳ-0009-0077)
国家科技重大专项(J2019-Ⅶ-0015-0155)
出版年
2024
国家科技期刊平台
NSTL
万方数据