| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a magnesium oxide sintered compact exhibiting good translucency over an infrared range from visible ray. <P>SOLUTION: Magnesium oxide powder having ≥99.9% purity and 3-15 m<SP>2</SP>/g specific surface area is formed into a formed body in which the density is ≥58% theoretical density, the content of Sc is ≥30 wt.ppm and ≤2,000 wt.ppm and the content of Al is ≥5 wt.ppm and ≤100 wt.ppm. The formed body is heat-treated and is subjected to primary firing at ≥1,250°C and ≤1,600°C under the atmosphere to have ≥94% theoretical density. The translucent magnesium oxide sintered compact is obtained by applying hot isostatic pressure treatment to the primarily fired body at ≥1,200°C and ≤1,600°C under 40-196 MPa. <P>COPYRIGHT: (C)2008,JPO&INPIT |
