We investigated the influence of mechanical activation (MA) and initial temperature T 0 on combustion temperature T c and burning velocity U c for 90% (Si + C) -10% (4B + C) mixtures as well as on product morphology. Mechanical activation was found to strongly change the size and morphology of Si and graphite particles (by a factor of 6-8), lead to accumulation of micro strains, and increase the reactivity of green mixture. An increase in T 0 was found to proportionally increase the values of T c and U c but produce little or no influence on the phase composition of product. The SiC powder consisting of 50-100 nm crystal lites was obtained by diminution of combustion product and then used to prepare, by hot pressing, a ceramic PVD target for magnetron sputtering.