In this study, Cu–25WC, Ni–25WC, and Fe–25WC (all in wt%) composite powders were produced via mechanical alloying (MA) and characterized for their potential utilization in particulate materials based technologies. The changes in the crystallite size (D) and lattice strain (ε) during the production of WC particle reinforced Cu, Fe, and Ni composite powders via MA were investigated. The Williamson–Hall (W–H) plot analysis and fundamental parameters approach (FPA) applied with Lorentzian function were used to evaluate ε and D of matrix phases from XRD results. With increasing MA, ε values of all matrix phases showed an increase whereas D values showed a decrease. In addition to that, lattice parameters a_Cu and a_Ni changed linearly with time, and a_Fe displayed a slight decrease. The XRD peak belonging to the Cu (111) plane shifted towards larger 2-theta angles in the same direction. Contrary to Cu, the Fe (110) peak shifted to lower angles with MA time. However, the XRD peak belonging to the Ni (111) plane changed alternately. Similar results were obtained from both W–H plot analysis and the FPA calculations. Minimum crystallite size and maximum internal strain rates were estimated for 8 h MA’ed Cu25WC, Fe25WC, and Ni25WC composite powders as 14.63 nm and 1.39%, 7.60 nm and 1.23%, and 17.65 nm and 1.13%, respectively. Transmission electron microscope observations were found in good agreement with the crystallite size of XRD calculations.

The effect of mechanical alloying and the sintering regime on the microstructural and the physical properties of W-SiC composites were investigated. Powder mixtures of W-20 vol.% SiC were mechanically alloyed (MA'd) using a Spex mill for 3 h, 6 h and 24 h. MA'd powders were characterized by Laser Diffraction Particle Size Analyzer, SEM and XRD investigations. MA'd W-20 vol.% SiC powder composites were sintered under inert Ar and reducing H2 gas conditions at 1680 °C and 1770 °C for 1 h. The microstructural and mechanical characterizations of the sintered samples were carried out by scanning electron microscope (SEM) and X-ray diffraction (XRD) and Vickers Hardness analyses. The addition of SiC remarkably increases the hardness of the composites. Hardness is also increased with decreasing grain size and increasing amount of MA. © 2009 Elsevier B.V. All rights reserved.TÜBİTAK project number 105M065 and DPT project number 2001K12075