Obtaining and Characterization of W-Cu Composite Powder Produced by Mixing and Sintering of Ammonium Paratungstate (Apt) and Copper Nitrate

The objective of this work is obtaining W-30 wt% Cu composite powder from ammonium paratungstate hydrated (APT) and hydrated copper nitrate and investigating the influence of some production process parameters of W- 30 wt% Cu in particles form which results in high sinterability and densification of W-30 wt% Cu composite. To achieve this objective, the powder was obtained by manually mixing the APT and copper nitrate and reducing under a hydrogen atmosphere at 800 °C and then compacting at 500 MPa and sintering in a tubular furnace at 1200 °C for 60 minutes. The obtained materials were characterized by XRD, SEM, EDS, particle size analysis, density and microhardness measurements. The composite powder showed a good homogenization of Cu in W with very fine and agglomerated particles and a mean crystallite size of 25.64 nm. SEM coupled with EDS with mapping analysis revealed a homogeneous distribution of Cu and W in the sintered sample. The composite had a relative density of 96.77% and a microhardness of 523.66 HV. Therefore the method of obtaining the composite powder is feasible to sinter W-30 wt% Cu powder due to a greater dispersion and homogenization of phases and the average particle size.本研究的目标为以水合仲钨酸铵（ammonium paratungstate hydrated, APT）与水合硝酸铜为原料，制备W-30wt%铜基复合粉末，并探究W-30wt%铜基复合材料粉体成型的若干工艺参数，以获得具备高烧结活性与致密度的目标复合材料。 为达成该研究目标，研究人员先手工混合APT与水合硝酸铜得到前驱体粉末，随后在800℃氢气气氛下进行还原处理，再以500MPa压力冷压成型，最后置于管式炉中于1200℃下烧结60分钟。 采用X射线衍射（X-ray Diffraction, XRD）、扫描电子显微镜（Scanning Electron Microscope, SEM）、能量色散X射线光谱（Energy Dispersive Spectroscopy, EDS）、粒度分析、密度测试与显微硬度测试对所得试样进行表征。 测试结果表明，所得复合粉末中铜在钨基体中分布均匀，颗粒细小且存在一定团聚，平均晶粒尺寸为25.64nm。 结合能谱面扫的SEM分析结果显示，烧结试样内铜与钨元素呈均匀分布。 该复合材料的相对密度达96.77%，显微硬度为523.66HV。 综上，由于该方法制备的复合粉末各相分散性与均匀性优异且平均粒度适宜，其可有效用于W-30wt%铜基复合材料的烧结制备。