当前位置：首页 > 过刊浏览->2023年44卷第3期
K403 合金高压导向叶片的组织及 热疲劳机理分析
Microstructure and Thermal Fatigue Mechanism of K403 Alloy High Pressure Guide-Vane
浏览(2695) 下载(9)
- DOI:
- 作者:
- 周中波 1，2 ，杨明波 1 ，张建中 2 ，韦皓博 1
ZHOU Zhongbo1,2, YANG Mingbo1 , ZHANG Jianzhong2 , WEI Haobo1
- 作者单位:
- 1. 重庆理工大学 材料科学与工程学院，重庆 400054；2. 重庆三耐科技有限责任公司，重庆 401135
1. Materials Science and Engineering College, Chongqing University of Technology, Chongqing 400054, China; 2. Chongqing Sannai Technology Co., Ltd., Chongqing 401135, China
- 关键词:
- K403 合金；高压导向叶片；热冲击；组织；热疲劳裂纹
K403 alloy; high pressure guide-vane; thermal shock; microstructure; thermal fatigue crack
- 摘要:
- 为了加快验证新工艺制造的 K403 合金高压导向叶片的可靠性，采用热冲击试验模拟叶片实际服役环境，
分析了热冲击前后叶片的微观组织及热疲劳裂纹的萌生及扩展机理。 研究结果表明，高压导向叶片经过 781 次热冲击
后，枝晶的二次枝晶间距明显增加，γ 基体通道变宽，γ′相含量由 53%降低至 45.1%。 疲劳裂纹不仅从叶片表面应力集中
部位萌生，叶身内部大块碳化物由于冷热循环作用而破裂也可形成裂纹源。 疲劳裂纹扩展速率在热冲击中前期由
于热应力得到释放从而逐渐减慢，在热冲击试验的中后期由于 γ′强化相逐渐减少，使得裂纹扩展阻力减少，裂纹扩展
速率加快。
To speed up the verification of the reliability of the K403 alloy high pressure guide vane manufactured by the new process, a thermal shock test was used to simulate the actual service environment of the blade. The microstructure of the blade before and after thermal shock and the initiation and propagation mechanism of thermal fatigue cracks were also analysed. The results show that the secondary dendrite spacing increases significantly, the γ-matrix becomes wider, and the γ′ phase content decreases from 53% to 45.1%. Fatigue cracks not only originate from the stress concentration part of the blade surface, but also form the source of cracks when the large carbides inside the blade body are ruptured due to the action of cold and heat cycles. The fatigue crack growth rate gradually slows down due to the release of thermal stress in the early stage of the thermal shock test, and the γ′ strengthening phase tends to decrease in the middle and late stages of the thermal shock test, which reduces the resistance to crack growth and accelerates the crack growth rate.