Sintering nano-polycrystalline clinopyroxene

Recently, ultrafine-grained rocks have attracted the growing interest due to their unique physical and mechanical properties. In this study, we investigated a method for prepareing nano-polycrystalline diopside and nano-polycrystalline salite from natural clinopyroxene. Ultrafine-grained clinopyroxene powders were prepared by crushing diopside single crystal (Ca0.92Na0.07Al0.06Mn0.01Mg0.93Fe0.01Si2O6) and salite single crystal (Ca0.97Na0.02Al0.02Mg0.86Fe0.13Si2O6) , and they were sintered under the flow of argon. At temperatures of 1180 ° and 1230 °, high dense nano-polycrystalline diopside and nano-polycrystalline salite with an average grain size of <500 nm were obtained. Moreover, nano-polycrystalline clinopyroxene specimens containing a trace amount of carbon were sintered from powders which absorbed CO2. Our experiments demonstrate new possibilities for scientific advancement with carbon-bearing nanocrystalline of mantle silicate minerals.