不同压力对挤压铸造Al-Cu-Mg合金性能的影响

Effect of Pressure on Squeeze Cast Al-Cu-Mg Alloy

使用挤压铸造工艺制备了高强、高韧Al-4.5Cu-1Mg合金。在挤压力为70MPa下成型后,合金的最大抗拉强度达到288.8MPa、伸长率达到12.8%、HRB硬度达到48.3。通过对该合金力学性能及其显微组织的研究表明,合金的抗拉强度、伸长率以及硬度随着压力的增加而增大,并且在70MPa时达到最大值,70MPa之后继续增加压力,对材料性能影响不大。研究了挤压力对合金的密度和导电性的影响。试验结果表明,合金的密度随着压力的增加而快速增大,在挤压压力为70MPa时达到最大值,然后变化不大。

Based on the chemical composition of Al-4.5Cu-1Mg alloy, an alloy suitable for squeeze casting was prepared by using a pressure of 70 MPa. It possesses an ultimate tensile strength of 288.8 MPa, elongation of 12.8% and a hardness of HRB 48.3 in as-cast state. Microstructure and mechanical property of the as-cast alloy were studied to determine the effect of the squeeze pressure on the casting. Results show that the ultimate tensile strength, elongation and density of the as-cast alloy increase with the applied pressure and reached a maximum at a pressure of approximately 70 MPa, then level off with a slightly drop. Effects of squeeze pressure on the density and electrical resistivity of the cast alloy were also studied. The density of the cast alloy increases sharply as the squeeze pressure increases, then leveled off after a squeeze pressure of approximately 70 MPa, which is in harmony with the maximum in mechanical property.