高Ni钎料-WC硬质合金颗粒复合堆焊焊条的探讨

Discussion on high-nickel solder-WC cemented carbide particle composite surfacing electrode

以SiC材质成型舟皿作为模具,尺寸为2~5 mm的YG8型WC硬质合金颗粒为耐磨相,CuZnNi合金为胎体金属,加入NiCrBSi合金粉末以提高胎体金属的Ni含量与Cr含量,采用钼丝氢气炉烧结制备高Ni钎料-WC硬质合金颗粒复合堆焊焊条,并对成型后焊条的断面形貌及胎体金属成分进行分析。结果表明,硬质合金颗粒在焊条内呈相对均匀的分布,胎体金属中Ni的质量分数高达32.39%,适量的Cr元素能够增强胎体金属的强度,同时提高胎体金属的耐腐蚀性能与高温抗氧化性能,用氧乙炔火焰堆焊时,胎体金属流动性好,与基体润湿性好,焊层内胎体金属硬度大于60HRA,可在石油、矿山等耐磨领域推广应用。

High-nickel solder-WC cemented carbide particle composite surfacing electrode was prepared by molybdenum wire hydrogen furnace sintering under the following conditions:SiC forming boat was used as the mold,YG8 WC cemented carbide particles with the size of 2-5 mm were used as the wear-resistant phase,and Cu-Zn-Ni alloy was used as the matrix metal.NiCrBSi alloy powder was added to enhance the nickel and chromium contents in matrix metal.The fracture morphology of the formed electrode and the composition of the matrix metal were analyzed.The results showed that the distribution of cemented carbide particles in the electrode was relatively uniform.The mass fraction of nickel in matrix metal was up to 32.39%.Appropriate amount of chromium could enhance the strength of matrix metal,and meanwhile improve the corrosion resistance and high temperature oxidation resistance.During the surfacing welding using oxyacetylene flame,the matrix metal had good fluidity and good wettability with the matrix.The hardness of matrix metal in the welding layer was greater than 60 HRA,which could be widely used in wear-resistant fields such as petroleum and mining.