Fabrication of W-20Cu composite with optimization of particle packing in PM route

The optimal design about the packing structure of W and Cu particles has become a focus of attention for developing the high performance W-Cu composites. In the present work, a series of numerical simulations and physical experiments were conducted to optimize the packing structure of W and Cu particles and establish the relation between particle size and sintering properties. The results reveal that the relative density and uniformity of the binary W-20Cu system showed a negative correlation with increasing size ratio of W and Cu particles. The optimal binary W-20Cu system can be formed when the size ratio of W/ Cu particle is 1.5 and the peaked uniformity can reach 0.986. The (W45-20Cu30)-20(W10-20Cu10) size ratio in ternary W-20Cu mixture was identified as the best packing structure by optimization calculation for multi-component system. The relative density of best ternary (W45-20Cu30)-20(W10-20Cu10) system can reach 0.625, which was 10.7% higher than that of binary W45-20Cu30 system. In the best packing structure with size ratio, the sintering properties of ternary W-20Cu composites were efficiently improved by reducing particle size. The W-20Cu composite with small particles showed a tensile/compressive strength over 147/442 MPa (1.73/1.62 times that of the W-20Cu composite with large particles), an electrical conductivity of 36 %IACS, and a hardness of 190 HV. These highlighted results can provide some valuable references for the design and optimization of high performance W-Cu composite in the route of powder metallurgy. (c) 2022 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).