This paper proposes a new strategy for inducing wear on a trim die to examine the degradation of edge stretchability with advanced high-strength steels. To independently examine trim die wear, the wear is categorized into abrasive wear and chipping-type abrasive wear. Geometric changes in fixed and moving trim dies were precisely examined every 2500 cycles of a repetitive trimming test lasting up to 15,000 cycles. A uniform wear shape could be generated after 5000 cycles; thus, it was possible to extrapolate the blanking cycles by controlling the die clearances, as well as realistically simulate chipping wear by micromachining the chipping shapes onto a worn trim die. The degradation rates of the edge fracture strain of DP980 and TRIP1180 were compared for various combinations of trimming die sets, which exhibited significantly different tendencies even though they had similar levels of initial edge stretchability. TRIP1180 had a high degradation rate of 35% for the edge stretchability after fewer than 15,000 cycles. In contrast, a degradation rate of 11% was observed when the DP980 sheet was applied, but the edge stretchability was highly sensitive to chipping-type abrasive wear.

本文提出了一种诱导修边模具磨损的新策略，以检查高级高强度钢边缘拉伸性的退化。为了独立检查修边模具磨损，磨损分为磨料磨损和崩刃型磨料磨损。在持续长达 15,000 次的重复修整测试中，每 2500 次循环对固定和移动修整模具的几何变化进行精确检查。5000次循环后可产生均匀的磨损形状；因此，可以通过控制模具间隙来推断冲裁周期，并通过在磨损的修整模具上微加工切屑形状来真实地模拟切屑磨损。比较了 DP980 和 TRIP1180 的边缘断裂应变的退化率，用于各种修边模组组合，尽管它们的初始边缘拉伸性水平相似，但它们表现出明显不同的趋势。TRIP1180 在少于 15,000 次循环后的边缘拉伸性具有 35% 的高降解率。相比之下，当应用 DP980 片材时，观察到 11% 的降解率，但边缘拉伸性对碎裂型磨料磨损高度敏感。