LOW THERMAL EXPANSION CERAMICS PLANE ASBESTOS CEMENT SHEET AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To produce a low thermally expanding ceramics plane asbestos cement sheet having a strength and hot creep resistance in combination. SOLUTION: This low thermally expanding ceramics plane asbestos cement sheet comprises a β-spodumene-based or a β-eucryptite-based material containing 1-10 wt.% of a metal oxide added as a sintering aid and has 250-600 kgf/cm2 bending strength, a size of >=500 mm length × 500 mm width and <=10 mm thickness. A mixed raw material containing a petalite-based raw material, a clay and the metal oxide added as the sintering aid is pulverized and prepared to 3-10 μm average particle diameter and water is then added to knead the prepared mixture. The resultant kneaded composition is subsequently ejected into a shape having a circular curve with a vacuum kneading machine. The ejected planar material is rolled and formed in the same direction as that of the ejection and then dried and baked.