Fabrication of dense forsterite–enstatite polycrystals for experimental studies

Abstract

 A practical and reliable method for the preparation of fine-grained forsterite and forsterite–enstatite polycrystals, in the system MgO–SiO₂, is described. The method employs state-of-the-art techniques from materials science, namely sol-gel synthesis, powder processing and sintering. The resulting dense polycrystalline materials are homogeneously fine-grained (1–2 μm) and uniformly foam-textured. Moreover, they are highly reproducible in composition and microstructure. The enstatite content can be controlled to within ∼1%, in the range 0–50%, and densities up to 98% of theoretical density can be achieved. The method thus yields polycrystalline forsterite–enstatite material suitable for a range of geochemical, petrological and geophysical studies.