共沉淀法制备超细Cu-Fe-Sn-Ni铜基预合金粉及其烧结胎体的抗弯强度

Preparation of ultrafine Cu-Fe-Sn-Ni Cu-matrix bonded pre-alloyed powder by co-precipitation method and its flexural strength of sintered matrix

以CuCl_2·2H_2O、FeCl_2·4H_2O、SnCl_2·2H_2O和NiCl_2·6H_2O为原料,用H_2C_2O_4·2H_2O作为沉淀剂,采用共沉淀法制备Cu-Fe-Sn-Ni四元铜基预合金粉,并用真空热压法制备Cu-Fe-Sn-Ni铜基胎体结块和胎体/金刚石结块。研究加料顺序、溶液p H值、陈化时间、反应温度和混合金属盐溶液的浓度对前躯体粉末粒度的影响,优化工艺参数。用X射线衍射仪和扫描电镜分析粉末的物相和形貌,并与采用混合单质粉末制备的节块抗弯强度进行对比。结果表明:共沉淀法制备Cu-Fe-Sn-Ni四元铜基预合金粉的最佳工艺为采用并加的加料方式、陈化时间为40min、反应温度为50℃以及混合金属盐溶浓度为1.0 mol/L。前驱体粉体经过煅烧和氢气还原后,得到粒度约为500 nm的超细Cu-Fe-Sn-Ni四元铜基预合金粉,热压后的胎体抗弯强度达到1 302 MPa,胎体/金刚石结块的抗弯强度为853 MPa,高于采用混合单质粉末制备的铜基胎体结块和胎体/金刚石结块抗弯强度(分别为992.5和782.5 MPa)。

Using CuCl2·2H2O,FeCl2·4H2O,SnCl2·2H2O and NiCl2·6H2O as raw materials,H2C2O4·2H2O solution as precipitator,Cu-Fe-Sn-Ni quaternary Cu-based pre-alloyed powder was fabricated by co-precipitation method.The sintered Cu-Fe-Sn-Ni cupric carcass and the carcass/diamond caking were prepared through hot pressing processes.The effects of charging sequence,pH value,aging time,co-precipitation temperature and solution concentration on the particle size of precursor powders were investigated.The phase composition and morphology of the powder were characterized by X-ray diffraction(XRD)and scanning electronic microscope(SEM).Moreover,the flexural strength of Cu-Fe-Sn-Ni quaternary pre-alloyed powder was tested,which was compared with that of the samples that was prepared by mixing the four kinds of elemental powders.The results show the optimal process of Cu-Fe-Sn-Ni pre-alloyed powder is a parallel-flow charging sequence,co-precipitation temperature of 50℃,aging time of 40 min and solution concentration of 1 mol/L.The ultrafine Cu-Fe-Sn-Ni pre-alloyed powder with particle size of about 500 nm can be obtained by calcining and hydrogen reducing the precursor powder.The flexural strength of the matrix is 1 302 MPa and the carcass/diamond caking is 853 MPa after hot pressing.