冷拔60Si2MnA钢丝的高强脉冲电流处理

由于加工硬化效应的影响,金属材料在发生塑性变形后其强度会增加.因此,冷拔钢丝的强度远高于拉拔前钢丝的强度,同时塑性变形能力远低于拉拔变形前.已发生较大拉拔变形的钢丝若需要进一步拉拔,常常需要采用高温退火方法来降低冷拔钢丝的强度和增加其塑性变形能力.本文将报道一种新的、可用于原位处理冷拔钢丝的高强脉冲电流处理方法.结果表明,在脉冲电流处理可使一种冷拔弹簧钢丝的强度显著降低,且塑性变形能力大幅增加.采用200 Hz的脉冲电流处理该冷拔弹簧钢丝1 min后,其力学性能与该钢丝在700℃条件下退火1 h后的力学性能相似.研究结果表明,高强脉冲电流处理方法是一种能使已发生加工硬化的金属材料有效软化的新方法.

High-density pulse current treatment of as-drawn 60Si2MnA wires

It is well-known that after plastic deformation the strength of metallic materials would be enhanced due to the effect of working hardening.As a result of working hardening,the strength of the as-drawn steel wires is much higher than that before drawing,but the deformation ability of the wires is reduced.For further deformation,high temperature annealing is usually used to reduce the strength and increase the plastic deformation ability of as-drawn wires.Here we report a new high-density electric pulse current processing method which can be used to in-situ treat the as-drawn wires.It is found that after elcctropulsing treatment the strength of a spring steel wire is significantly reduced while its plastic deformation ability is greatly enhanced.The mechanical properties of the as-drawn wires treated with 200 Hz pulse current for 1 minute is very similar to that of the wires annealed at 700 ℃ for 1 hour.It suggests that high-density electric pulse current treatment is an efficient processing way to soften the work-hardened metallic materials.