ホットフォージ成形した MgO ならびに MgO-SiC ウィスカー複合焼結体

概要

論文の詳細を見る
Ultra fine MgO powders with or without a small amount of SiC whidker were capsulated in a metallic mold with dimensions of O.D.22φ─I.D.10φ×30 lmm. The mold was preheated at a temperature of 900°-1600℃ for 8-10 minutes, and was press-forged in few seconds under an uniaxial compressive load. The deformati ratio of the mold was about 30% of the original height, and the maximum pressure was about 5000 kgf/cm^2. the polycrestalline MgO without SiC whisker prepared by the hot-forge processing at 1300℃ was composed of submicron grains, and its Vickers hardness was almost the same as that of the theoretically dense polycrystalline MgO prepared by hot-pressing. The hardness of the MgO-SiC whisker composite ceramics prepared by this processing, on the otherhand, decreased with increasing whisker content, and the whiskers in the composites were preferentially orientated perpendicular to the press-forging axis. The fracture toughness of the MgO-SiC whisker composite ceramics was about 1.5 times a large as that of the polycrystal without SiC whisker.
社団法人日本材料学会の論文
1989-11-15