Synthesis and deformation behavior of nano-diphasic materials from natural dolomite

Nano-grained CaO/MgO and related composites have been synthesized from the mixed carbonate mineral, dolomite (CaMg(CO3)2), by pyrolytic reactive sintering. In CaO/MgO composites, CaO and MgO grains mutually inhibited the other’s grain growth. Effects of LiF doping on decomposition and sintering of dolomite were studied. The CaO/MgO nanocomposite with a small amount of LiF showed superplastic-like deformation at high temperatures. A preliminary machining test revealed that the CaZrO3/MgO in situ nanocomposite, which was synthesized from dolomite/zirconia mixed powder, was machinable at room temperature accompanying quasiplastic deformation.