Reactions of IVa-group metals, Ti and Zr, with uncracked NH3 gas at a temperature in the range between 600 and 800 °C under heating with concentrated solar beam at PSA

Abstract

Low-temperature (600–800°C) short-time (30–90min) nitriding of IVa-group transition metals, Ti and Zr, in flow of NH3 gas (uncracked ammonia) was carried out under heating with concentrated solar beam in the vertical type SF5 solar furnace at PSA (Plataforma Solar de Almería) in Tabernas, Spain. Due to low nitriding temperature and short reaction duration, full conversion of starting metallic material to nitride was not realized as a matter of course. Nevertheless, detectable extent of nitriding appeared to have progressed for both metallic Ti and Zr at the reaction temperature higher than 700°C to yield mono-nitride MN possessing face centred cubic (fcc) lattice co-existed with M solid-solutioned with N possessing hexagonal closed packed (hcp) lattice. Such partially nitrided powders might be accepted as convenient starting material for combustion synthesis (CS) of near net shape component of nitride ceramics.