Creep behaviour of silicon carbide whisker reinforced alumina/zirconia composites

Abstract

W-Cu composite materials with various molar ratio of constituent metals (W:Cu = 2:1 and 1:3) were synthesized via co-reduction of WO3 and CuO oxides precursors with Mg + C combined reducer in the combustion mode by applying reaction's thermo-kinetic coupling approach. The interaction mechanism and phase and microstructure formation laws in the 2WO3-CuO-yMg-xC and WO3-3CuO-yMg-xC quaternary systems were explored. According to experimental results obtained by stopped combustion front technique in bulk copper wedge, it was shown that firstly the copper oxide carbothermal reduction into copper and then magnesio-carbothermal reduction of the tungsten oxide into tungsten take place. It was revealed that the growth of C/Mg ratio leads to decrease both the combustion temperature and velocity conditioned by growth in the portion of low-caloric reaction and allows to control interaction conditions for the preparation of nanosized 2 W-Cu and W-3Cu composite powders. Combustion products obtained at optimum conditions represent as W-Cu nanocomposite powder with 30–50 nm in size.