基于数字图像相关方法的FGH96疲劳裂纹扩展分析  

Analysis of FGH96 fatigue crack growth based on the digital image correlation method

作　　者：苗国磊 施祎 杨晓光[3,4] 石多奇 MIAO Guo-lei;SHI Yi;YANG Xiao-guang;SHI Duo-qi(Chengdu Holy Industry&Commerce Corp.Ltd,Pengzhou 611936,China;Special Material Institute,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai 200240,China;School of Energy and Power Engineering,Beihang University,Beijing 100191,China;Collaborative Innovation Center for Advanced Aero-Engine,Beijing 100191,China)

机构地区：[1]成都航利(集团)实业有限公司,四川彭州611936 [2]上海交通大学材料科学与工程学院特种材料研究所,上海200240 [3]北京航空航天大学能源与动力工程学院,北京100191 [4]先进航空发动机协同创新中心,北京100191

出　　处：《燃气涡轮试验与研究》2022年第4期1-6,50,共7页Gas Turbine Experiment and Research

基　　金：国家自然科学基金(52105156);中国博士后基金(2022M712062)。

摘　　要：基于非接触全场高精度测量的数字图像相关(DIC)方法,对粉末镍基高温合金FGH96开展室温下的裂纹扩展试验。试验过程中,首先,利用DIC系统记录单边缺口试样循环载荷下的裂纹变化图像,由此获得裂纹扩展速率情况;其次,利用相关算法结合不同的计算策略,可获得裂纹尖端最大总应变场以及累计塑性应变场的演化规律;再次,基于最小二乘法对已有的位移场进行回归分析,可提取裂纹尖端应力强度因子获得裂纹扩展驱动力;最后,利用裂纹张开位移与载荷的关系,观察闭合现象并获得裂纹张开应力范围。The fatigue crack growth test of powder metallurgy nickel-based superalloy FGH96 was conducted at room temperature based on non-contact and high-resolution measurement named Digital Image Correlation(DIC). During the test process, firstly, images of single notched specimen evolution under cyclic loading were captured by DIC system and thus the crack growth rate was obtained. Then,combined with the relevant algorithm and different analysis strategies, the evolution of total strain filed and residual plasticity strain field at the crack tip was obtained. Again, based on the least square method,the stress intensity factor and crack growth driving force at the crack tip can be deduced by the regression of the displacement filed. Finally, the crack closure phenomenon was observed and the crack opening load rage was calculated according to the relationship between the crack opening displacement and loading.

关 键 词：FGH96 数字图像相关方法 裂纹扩展 裂纹尖端应变场 应力强度因子 

分 类 号：V231.95[航空宇航科学与技术—航空宇航推进理论与工程]