4Cr5MoSiV1模具钢的表面复合处理对压铸过程和制成品的影响评估

Assessment of the Effect of Surface Compound Treatment of 4Cr5MoSiV1 Die Steel on the Die Casting Process and the Finished Product

摘要: 对4Cr5MoSiV1模具钢，进行了渗氮和喷丸相结合的表面处理，并对压铸过程的影响和制成品的抗拉强度进行了评估。对于3种模具：未经处理的模具、SB-N处理模具和SB-N-SB处理模具(Shot Blasting抛丸；Nitriding渗氮)，考察了其压铸过程和制成品。通过在模具的3个挤压销上安装应变片，以捕捉注射过程中的应变值。通过考察应变曲线中压力上升的时间差、最大应变值和压力持续时间，明确了不同表面处理方法对熔融金属的流入和凝固过程有较大影响。对应变曲线的分析表明：经过表面处理的模具其流动性、压力传播特性和热保持性均得到了改善。通过X射线CT观察了3种模具的ADC12铝合金压铸试样，并测试了抗拉强度，结果表明：经过SB-N-SB表面处理的模具其制成品缺陷的大小和数量更小，抗拉强度平均提高约10%，可有效提高模具的耐用性和铸件的质量。

Abstract: For 4Cr5MoSiV1 die steel, a combination of nitriding and shot blasting surface treatment was per-formed, and the effects of the die casting process and the tensile strength of the manufactured products were evaluated. For three types of dies: untreated dies, SB-N treated dies and SB-N-SB treated dies (Shot Blasting; Nitriding), the die casting process and manufactured products were examined. Strain gauges were installed on the three extrusion pins of the die to capture the strain values during the injection process. By examining the time difference of pressure rise, maximum strain value and pressure duration in the strain curve, it was clear that different surface treatment methods have a large effect on the inflow and solidification process of molten metal. The analysis of the strain curves showed that the flow, pressure propagation characteristics and heat retention of the surface-treated molds were improved. The ADC12 aluminum alloy die-casting specimens of three molds were observed by X-ray CT and tested for tensile strength. The results showed that the molds with SB-N-SB surface treatment had smaller size and number of defects in their manufactured products, and the tensile strength was increased by about 10% on average, which could effectively improve the durability of the molds and the quality of the castings.