In the present paper, a novel criterion for fatigue life assessment of engineering components under multiaxial low-cycle fatigue regime is proposed. The criterion, named Refined Equivalent Deformation (RED) criterion, allows to take into account, when the load is non-proportional, the fatigue strength decrease experimentally observed for those metals sensitive to non-proportionality. The criterion is applied to two different metals (304 stainless steel and 6061 aluminum alloy) characterised by different non-proportional sensitivities. The accuracy of such a criterion is compared with those of other criteria available in the literature.

中文翻译：

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非比例载荷下金属疲劳寿命评估的RED准则

在本文中，提出了一种新的多轴低周疲劳状态下工程部件疲劳寿命评估标准。该标准称为精炼等效变形 (RED) 标准，允许考虑当载荷不成比例时，对非成比例敏感的金属的疲劳强度通过实验观察到降低。该标准适用于具有不同非比例敏感性的两种不同金属（304 不锈钢和 6061 铝合金）。将此类标准的准确性与文献中可用的其他标准的准确性进行比较。