时效态高强高导Cu-Ag-Cr合金的组织与性能

Microstructures and Properties of Aging Cu-Ag-Cr Alloy with High Strength and High Conductivity

采用真空熔炼的方法制备了Cu-4Ag-0.8Cr合金,经时效处理后,可获得抗拉强度为585 MPa,电导率为85%IACS的高强高导铜合金。采用金相显微镜(OM)、扫描电镜(SEM)、涡流导电仪、万能材料试验机研究了合金的组织与性能。结果表明,Cu-4Ag-0.8Cr合金在不同工艺下时效时,析出相存在两种形态,球状和三叉状。随着时效温度的升高,析出相逐步长大,且分布不均匀。随时效时间的延长,Cu-4Ag-0.8Cr合金的导电率不断增加,最后趋于恒值,而合金的抗拉强度先增加,达到峰值后急剧降低。合金在直流阻性负载条件下的电弧侵蚀表面显示出大量的浆糊状凝固物和喷发坑。

Cu-4Ag-0.8Cr alloy with tensile strength of 585 MPa and electrical conductivity of 85% IACS was prepared by vacuum melting and aging treatment. The microstructures and properties of the alloy were studied by optical microscopy （ OM）, scanning elec- tron microscopy （SEM） , eddy current conductive instrument and universal material testing machine. The results showed that, under different aging process conditions, there were spherical and trident precipitated phases in the Cu-4Ag-0.8Cr alloy matrix. With the ag- ing temperature increasing, the precipitates distributed non-homogeneously and the size became larger. With the aging time extension, the conductivity of the alloy increased at the beginning and finally tended to constant, while the tensile strength of the alloy increased first and then drastically reduced. The arc erosion surface of the material under DC load showed a lot of pasty coagulum and eruption pits.