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采用钨粉表面化学镀铜与SPS固相烧结2种工艺相结合的方法,制备出具有低W-W连接度特征及以黄铜作为粘结相的W-Cu-Zn合金,研究了热处理工艺对合金组织与性能的影响。微观分析表明所制备出的W-Cu-Zn合金中,钨颗粒均匀分布在黄铜粘结相中,粘结相为α相Cu-Zn固溶体。热处理后钨与黄铜粘结相的两相分布没有发生变化,但力学性能变化显著,经870℃随炉冷却热处理后,W-Cu-Zn合金硬度(HV)由1438 MPa提高至1723 MPa,准静态压缩加载时抗断裂强度由650 MPa提高至750 MPa,临界失效应变由0.18增大至0.26,静态力学性能显著提高。动态压缩加载时抗断裂强度由710 MPa提高到900 MPa,临界失效应变由0.24提高到0.4,动态力学性能显著提高。机理分析表明,热处理前W-Cu-Zn合金的黄铜粘结相中存在Zn元素分布不均的现象,经870℃随炉冷却热处理后黄铜粘结相中Zn元素分布的均匀性大幅度提高,这是合金力学性能提高的原因之一;此外,热处理后黄铜粘结相中形成了大量细小弥散分布的Cu_3Zn析出相,起到弥散强化作用,这是合金的强度显著提高的另一个原因。
W-Cu-Zn alloy with low WW connectivity and brass as binder phase was prepared by a combination of chemical plating of tungsten powder and SPS solid state sintering. The effects of heat treatment on the wear resistance of the alloy The impact of organization and performance. The microscopic analysis shows that the tungsten particles are uniformly distributed in the brass binder phase and the binder phase is the α-phase Cu-Zn solid solution in the prepared W-Cu-Zn alloy. After heat treatment, the phase distribution of the binder phase of tungsten and brass did not change, but the mechanical properties changed significantly. The hardness (HV) of W-Cu-Zn alloy increased from 1438 MPa to 1723 MPa after heat treatment at 870 ℃ in the furnace, The tensile strength at quasi-static compression loading increases from 650 MPa to 750 MPa, the critical failure strain increases from 0.18 to 0.26, and the static mechanical properties increase significantly. The tensile strength at dynamic compression loading increased from 710 MPa to 900 MPa, the critical failure strain increased from 0.24 to 0.4, and the dynamic mechanical properties remarkably improved. The mechanism analysis shows that there is an uneven distribution of Zn elements in the W-Cu-Zn alloy before heat treatment. The homogeneity of Zn distribution in the binder phase of the brass after heat treatment at 870 ℃ Which is one of the reasons for the improvement of the mechanical properties of the alloy. In addition, a large number of precipitated phases of finely dispersed Cu_3Zn are formed in the binder phase of the brass after heat treatment, which has the effect of dispersion strengthening, which is another significant improvement in the strength of the alloy the reason.