Stress intensity measurement via infrared focal plane array
Stress intensity measurement via infrared focal plane array
复制标题
通过红外焦平面阵列测量应力强度
DOI：
10.1520/stp11902s
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
C. Welch
中科院分区：
文献类型：
--
作者：
JR Lesniak;DJ Bazile;B. Boyce;MJ Zickel;K. E. Cramer;C. Welch
概述了一种用于测量动态加载疲劳裂纹样本中应力强度因子的全场热弹性技术。热弹性应力分析 (TSA) 使用红外焦平面阵列探测器和高速处理电子设备来生成循环加载样本的应力图像。然后将 TSA 数据与拟合算法结合使用，以确定 I 型以及 I 型和 II 型混合裂纹几何形状的应力强度因子。该技术非接触式、快速、准确，有可能大大提高疲劳和断裂测试的效率。根据第一应力不变量导出了完整应力状态的解析解，以支持全场 TSA 技术。给出了在模式 I 和混合模式样本上使用该技术的结果，并显示出与公认值的良好一致性。
A full-field thermoelastic technique for measuring stress intensity factors in dynamically loaded fatigue crack specimens is outlined. Thermoelastic Stress Analysis (TSA) uses an infrared focal plane array detector and high-speed processing electronics to produce stress images of cyclically loaded specimens. The TSA data is then used in combination with a fitting algorithm to determine stress intensity factors for mode I and mixed mode I and II crack geometries. The technique is non-contacting, fast and accurate, and has the potential to greatly enhance the efficiency of fatigue and fracture testing. An analytical solution for the complete stress state in terms of the first stress invariant is derived in support of the full-field TSA technique. Results using the technique on mode I and mixed mode specimens are presented, and show good agreement with accepted values.