航空学报 > 1982, Vol. 3 Issue (2): 105-111

镍基高温合金蠕变裂纹扩展的微观力学分析

申辉旺, 高振涛, 刘长富, 蔡其巩   

  1. 北京钢铁研究院
  • 收稿日期:1981-01-01 修回日期:1900-01-01 出版日期:1982-06-25 发布日期:1982-06-25

MICROMECHANICAL ANALYSIS OF CREEP CRACK GROWTH ON A NICKEL-BASE SUPERALLOY

Shen Huiwang, Gao Zhentao, Liu Changfu, Cai Qigung   

  1. Central Iron and Steel Research Institute
  • Received:1981-01-01 Revised:1900-01-01 Online:1982-06-25 Published:1982-06-25

摘要: 光滑和预制裂纹的高温合金试件的应力持久寿命的实验结果说明,预先存在的小裂纹,严重地降低高温合金构件的应力持久强度和寿命。 扫描电镜和金相照片分析说明,裂纹沿晶界孔洞扩展。根据孔洞增长和与主裂纹顶端会合的微观力学分析,用蠕变J积分参量和裂纹张开位移速率推导出蠕变裂纹扩展公式。GH_(33A)高温合金的实验数据论证了上面的断裂力学分析。

Abstract: Experiment on stress rupture life of smooth and precracked superalloy specimens shows that small preexisting crack seriously reduces the stress rupture strength and life of superalloy components.SEM and metallographic analysis indicate that the crack grows along grain boundaries by cavitation. Based on micromechanical analysis of the cavity growth and coalescence with the main crack tip, creep crack growth formulas were derived by using creep J integral parameter J and COD rate parameter δ. Experimental data on GH33A superalloy have verified the above fracture mechanical analysis.