| 摘要 |
PROBLEM TO BE SOLVED: To provide a glass-mold forming mold having good release property which does not cause any problems even when the glass contains B or Pb, and to provide the producing method of the mold. SOLUTION: A glass mold forming mold consists of a silicon carbide sintered body, and the silicon carbide sintered body has a smooth polished surface having pores of >=5 μm size by <=20 pores per 1 mm2 density measured by an optical microscope. The inner face of the mold has a silicon nitride film on the polished face of the sintered body. In the producing method of the glass mold forming mold, 0.1 to 0.5 wt.% boron and 1 to 5 wt.% carbon are added and mixed with silicon carbide powder having <=0.7 μm average particle size. The mixture is molded and sintered at 1,900 to 2,050 deg.C in and inert gas under normal pressure and then subjected to HIP treatment at >=1,000 kg/cm2. The surface of the obtd. sintered body is polished, and a silicon nitride film is formed by CVD method on the polished face. |
