In this study, the parameters of the Johnson-Cook model of SWRH82B steel are determined to describe the dynamic mechanical properties and fracture behaviors of steel wires. A total of 299 specimens are tested to determine the parameters. Quasi-static tensile tests at varying temperatures (20–700 °C) and different strain rates (10⁻⁴–10 ⁻² s ⁻¹) and split Hopkinson pressure bar tests are conducted to identify the parameters of the Johnson-Cook model. Notch tensile tests are conducted to calibrate the Johnson-Cook fracture criterion model. The wires made from SWRH82B high-strength steel with different diameters and shapes have different material performance due to different manufacturing and cold-drawing process. Therefore, two cross-section types (circular and Z shapes) and seven diameters of high-strength steel wires are considered for the material characteristic tests. The strain rate hardening effect is not significant at low loading rates but has a remarkable effect at loads exceeding. Analysis of the stress-strain curves at elevated temperatures shows that the thermal softening effect of the two types of wires is evident and that the temperature sensitivity varies in different temperature ranges. In addition, the mechanical performance of circular wires with diameters ranging from 4.0 to 5.2 mm and Z-shaped wires with diameters from 4 to 6 mm are compared. Fractography of SWRH82B high-strength steel is conducted to investigate the failure mechanism at various temperatures and strain loading rates. Finally, an improved Johnson-Cook model is proposed considering the strain hardening of SWRH82B steel wires based on different shapes and diameters.

在本研究中，确定了 SWRH82B 钢的 Johnson-Cook 模型参数来描述钢丝的动态力学性能和断裂行为。总共测试了 299 个样本以确定参数。在不同温度 (20–700 °C) 和不同应变率 (10 ^-4 –10 ^-2 s ^-1) 和拆分霍普金森压力棒测试，以确定约翰逊库克模型的参数。进行缺口拉伸试验以校准 Johnson-Cook 断裂准则模型。由SWRH82B高强钢制成的不同直径和形状的线材由于制造和冷拔工艺不同而具有不同的材料性能。因此，材料特性试验考虑了两种横截面类型（圆形和Z形）和七种直径的高强度钢丝。应变率硬化效应在低加载率下不显着，但在超过加载率时有显着影响。高温应力-应变曲线分析表明，两种线材的热软化效应明显，且温度敏感性在不同温度范围内有所不同。此外，直径为 4.0 至 5.2 毫米的圆形线材的机械性能和比较了直径为 4 至 6 毫米的Z形线材。对 SWRH82B 高强度钢进行断口分析以研究不同温度和应变加载速率下的破坏机制。最后，基于不同形状和直径的SWRH82B钢丝的应变硬化，提出了改进的Johnson-Cook模型。