Sintering nanocrystalline diopside from pulverized diopside crystals

The sintering behavior of diopside nano-sized powder was studied. We successfully fabricated diopside nanosized powders from naturally occurring diopside single crystal (Ca_0.92Na_0.07Mn_0.01Mg_0.93Fe_0.01Al_0.06Si₂O₆). Di- opside polycrystalline is sintered from powders with an average particle size of <100 nm under argon flow at temperatures ranging from 1130-1280 °C for 0.5-20 h. The average grain size increased with increasing sintering time and sintering temperature while porosity remained nearly constant value of 3-4 vol%. The experimental data of grain growth at 1180 °C can be fit for the following equation G³ - G³₀ = kt, where G is the grain size after time t, G₀ is the grain size at t = 0, and k is a rate constant.