Abstract For the first time, performance of the Equivalent Material Concept (EMC) in investigating fracture of V-notched ductile members subjected to mixed tension/out-of-plane shear loading, so-called mixed mode I/III loading, is examined. On the basis of EMC, a ductile material can be equated with a virtual brittle material in order to avoid conducting elastic–plastic analyses. In the present research, a new set of fracture experiments are carried out under several mixed mode I/III loading cases on the V-notched test samples fabricated from Al7075-T6 aluminum alloy and having various notch opening angles and notch tip radii. Combination of EMC with the two stress-based brittle fracture criteria of the point stress (PS) and mean stress (MS) is employed to estimate the load-carrying capacity (LCC) of all the samples tested. Comparing the theoretical predictions with experimental results approves that both EMC-PS and EMC-MS models are accurate in assessing mixed mode I/III fracture of V-notched Al7075-T6 specimens, and both criteria have almost the same efficiency. Additionally, it is revealed that irrespective of the magnitude of the notch opening angle, the predictions of both models about fracture toughness of the V-notched specimens are more accurate for V-notches with smaller notch tip radius.

中文翻译：

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在 V 型缺口 Al7075-T6 钢板的混合模式 I/III 断裂估计中等效材料概念的评估

摘要 首次研究了等效材料概念 (EMC) 在研究 V 型缺口韧性构件在混合拉伸/平面外剪切载荷下，即所谓的混合模式 I/III 载荷下的断裂中的性能。在 EMC 的基础上，韧性材料可以等同于虚拟脆性材料，以避免进行弹塑性分析。在目前的研究中，对由Al7075-T6铝合金制成的具有各种缺口开口角度和缺口尖端半径的V型缺口试样在几种混合模式I / III加载情况下进行了一组新的断裂实验。将 EMC 与点应力 (PS) 和平均应力 (MS) 这两个基于应力的脆性断裂标准相结合，用于估计所有测试样品的承载能力 (LCC)。将理论预测与实验结果进行比较，证明 EMC-PS 和 EMC-MS 模型在评估 V 型缺口 Al7075-T6 试样的混合模式 I/III 断裂方面是准确的，并且两种标准的效率几乎相同。此外，研究表明，无论缺口开口角的大小如何，对于具有较小缺口尖端半径的 V 型缺口，两种模型对 V 型缺口试样的断裂韧性的预测都更准确。