Abstract Fracture mechanical testing of micro-sized cantilevers was conducted in order to quantify the fracture toughness and behaviour of the (1 0 0)[0 1 ¯ 1] crack system in α-iron at 37.5 K, 133 K and room temperature. The cantilevers are outside the range of validity for linear-elastic fracture mechanics due to the small sample size, rendering the cantilevers out of bounds in relation to linear-elastic fracture mechanics and classical fracture mechanics. Elastic-plastic fracture mechanics has therefore been applied to determine the conditional fracture parameters KQC and JQC. A comparison between cantilevers continuously loaded with corrected dynamic stiffness measurements and another data set of cantilevers tested with the unloading compliance method has been made. A distinct difference in determined fracture toughness and crack behaviour was identified, indicating potential concerns when applying the unloading compliance method at the micro-scale on ductile materials.

中文翻译：

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微观尺度的断裂韧性测试——卸载柔量法的影响

摘要 为了量化α-铁中(1 0 0)[0 1 ¯ 1]裂纹系统在37.5 K、133 K和室温下的断裂韧性和行为，进行了微型悬臂的断裂力学测试。由于样本量小，悬臂超出了线弹性断裂力学的有效性范围，使得悬臂超出了线弹性断裂力学和经典断裂力学的范围。因此，弹塑性断裂力学已被应用于确定条件断裂参数 KQC 和 JQC。已经对使用修正的动态刚度测量值连续加载的悬臂与使用卸载柔度方法测试的悬臂的另一个数据集进行了比较。