公开(公告)号：US08163266B2

公开(公告)日：2012-04-24

申请号：US12441617

申请日：2007-09-18

申请人： Norifumi Azuma ,  Shinji Fujiwara

发明人： Norifumi Azuma ,  Shinji Fujiwara

IPC分类号： C01F7/02

CPC分类号： C30B29/20 ,  C01F7/02 ,  C01F7/442 ,  C01P2004/51 ,  C01P2004/52 ,  C01P2004/60 ,  C01P2006/10 ,  C01P2006/11 ,  C01P2006/12 ,  C01P2006/14 ,  C01P2006/80 ,  C01P2006/82

摘要： α-Alumina powder having a purity of at least 99.99% by weight, a specific surface area of from 0.1 to 2.0 m2/g, a relative density of from 55 to 90%, and a closed porosity of 4% or less, wherein in a weight-based particle size distribution obtained by the dry sieving test according to JIS K0069 (1992), an amount of particles having a particle size of less than 75 μm is 5% by weight or less; an amount of particles having a particle size exceeding 2.8 mm is 15% by weight or less; and at least one frequency maximum peak appears in a particle size range of 100 μm or more and to less than 850 μm. This α-alumina powder can be charged in a crucible at a high bulk density, from which sapphire having a few voids can be produced without causing the oxidation of a crucible in a heat melting step.

摘要翻译： 纯度为99.99重量％，比表面积为0.1〜2.0m 2 / g，相对密度为55〜90％，闭孔率为4％以下的α-氧化铝粉末，其中， 通过根据JIS K0069（1992）的干法筛分试验得到的重量型粒度分布，粒径小于75μm的粒子的量为5重量％以下; 粒径超过2.8mm的粒子的量为15重量％以下; 并且至少一个频率最大峰出现在100μm以上且小于850μm的粒度范围内。 该α-氧化铝粉末可以以高的堆积密度装入坩埚中，从而可以在坩埚中产生具有少量空隙的蓝宝石，而不会在加热熔融步骤中引起坩埚的氧化。