| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a large meter-sized ceramic capable of suppressing the reflectance of light low, exhibiting semiconductivity, consisting essentially of alumina and having ≥65GPa cm<SP>3</SP>/g specific rigidity. <P>SOLUTION: The alumina ceramic contains 80-90 % Al, ≥0.5% each of 3 elements of Mn, Ti and Fe and 2-11% in total of 3 elements, ≥4% Si, ≥0.4% Ca and Mg respectively and 6-9% in total of 3 elements, each expressed in terms of oxide, and is manufactured by controlling to form a Mn-Al spinel crystal and an anorthite crystal by firing without necessitating special atmosphere in the firing. <P>COPYRIGHT: (C)2004,JPO |
