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

Abstract

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.

Keywords:
Composite W-Cu; Ammonium Paratungstate; Copper Nitrate