高压时效处理对熔渗态Cu-W合金组织及性能的影响

对熔渗态Cu-W合金分别进行不同工艺的常压和高压时效处理,利用金相显微镜、扫描电镜、透射电镜、硬度计及电阻率测试仪,对比分析了两种时效工艺所获得合金的显微组织及力学和导电性能的差异,探讨了高压时效处理对Cu-W合金组织及性能的影响。结果表明,高压时效处理能增大Cu-W合金的致密度,使组织中的析出相分布更加弥散细小,改善了Cu-W合金的力学性能及导电性能。该合金经950℃×1 h固溶后,再在3 GPa压力下500℃时效1 h处理可获得较高的硬度、压缩屈服强度及较低的电阻率,分别为164 HV、221 MPa和4.415×10-8Ω·m,较相同工艺常压时效处理后合金的硬度和压缩屈服强度分别增加了21.48%和31.55%,而电阻率却降低了8.89%。

Effect of High Pressure Aging Treatment on Microstructure and Properties of Infiltrated Cu-W Alloy

The normal pressure and high pressure aging treatments of infiltrated Cu-W alloys by different processes were carried out. The microstructures, mechanical properties and electrical conductivity of the alloy obtained by two ageing processes were analyzed by means of metallographic microscopy, scanning electron microscope, ransmission electron microscope, hardness tester and resistivity tester. The effect of high pressure aging treatment on the microstructure and properties of Cu-W alloy was discussed. The results show that high pressure aging treatment can increase the density of Cu-W alloy and the precipitate distribution in the tissue is more dispersed and finer, consequently, the mechanical properties and electrical conductivity of Cu-W alloy are improved. Higher hardness, compressive yield strength and lower resistivity of the alloy can be obtained by solid solution at 950 ℃ for 1 h and aging at 500 ℃ for 1 h at 3 GPa pressure, its values are 164 HV, 221 MPa and 4.415×10-8Ω·m, respectively. The hardness and compressive yield strength of the alloy increased by 21.48% and 31.55%, but the resistivity decreased by 8.89% compared with that of the alloy treated by the same process under normal pressure.