Unloading compliance (UC) method and normalization method (NM) are two of the most commonly used methods for determining the fracture toughness of materials. However, considerable differences often exist in the fracture toughness determined by these two methods, which solicits a new method to determine the fracture toughness accurately. In this paper, the compliance of crack length differences is discovered, analyzed, and verified by experiments. Based on this compliance, a new accurate method, known as the accurate J‐R curve method (AJR), is developed and verified by test results. It is found that the J‐R curves determined by the new AJR method are more accurate than those determined by UC and NM. The developed new AJR method and the results presented in this paper can assist engineers and researchers to determine J‐R curves and fracture toughness of steels more accurately and can contribute to the body of knowledge of fracture mechanics.

中文翻译：

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确定钢的精确J-R曲线的新方法

确定材料的断裂韧性的最常用方法有两种：顺应性（UC）法和归一化方法（NM）。然而，通过这两种方法确定的断裂韧性通常存在相当大的差异，这寻求了一种准确确定断裂韧性的新方法。本文通过实验发现，分析和验证了裂纹长度差异的一致性。基于此合规性，开发了一种新的精确方法，称为精确J ‐ R曲线法（AJR），并通过测试结果进行了验证。发现J通过新的AJR方法确定的‐R曲线比UC和NM确定的更精确。开发出的新的AJR方法和本文中介绍的结果可以帮助工程师和研究人员更准确地确定J- R曲线和钢的断裂韧性，并有助于断裂力学的知识体系。