松装熔渗法制备高强高导铜钨合金

Preparation of High-strength and High-conductivity Copper-tungsten Alloys by Loose-packing and Infiltration Method

选取平均粒度分别为50nm、7μm,纯度为99.9%的钨粉,采用松装熔渗法制备高强高导铜钨合金,研究其显微组织和相关性能。结果表明,采用松装熔渗法可以制备高强高导铜钨合金,钨粉越细则其烧结性能越好,其致密度高,硬度和强度也较高,但是粉末粒度达到纳米级时,铜相会产生一定程度的偏聚,影响合金组织的均匀性。松装钨粉的孔隙率随着粉体平均粒径的减小而增大。7μm钨粉所制合金抗拉强度为370MPa,电导率为43.34μΩ-1·m-1,硬度HB为80.4,含铜量为65%;50nm的钨粉所制合金抗拉强度为410MPa,电导率为37.07μΩ-1·m-1,硬度HB为112,含铜量为73%。

The microstructure and related properties of the high strength and high conductivity tungsten copper alloy which was prepared by loose-packing and infiltration method with the average tungsten granularity of 50 nm and 7 μm as well as 99.9% purity were investigated.The results show that the high strength and high conductivity Cu-W alloy can be prepared by loose-packing and infiltration method.With the decrease of W powder size,the alloy is improved increasingly in the sintering behavior,density,hardness and strength.However,with the powder granularity reaching to nanometer grade,microstructure uniformity of the alloy is decreased as a result of the segregation of copper phase.The porosity of the loose-packing W powder is increased with decreasing in average diameter of powder granularity.The tensile strength,electric conductivity,hardness and Cu content of the alloy prepared with 7 μm W powder reach 370 MPa,43.34 μΩ-1·m-1,80.4 and 65%,respectively,and those of the alloy prepared with 50 nm reach 410 MPa,37.07 μΩ-1·m-1,112,73%,respectively.