| 摘要 |
Hot pressing process for compacting refractory materials, with a repeating operating cycle, comprising the following steps: (a) maintaining a mould at a compacting temperature in an enclosure containing an oxygen-free atmosphere. (b) Introducing measured quantities of refractory material into the mould. (c) Applying a pressure of 3.5-70 kg/cm2 for partial compaction. (d) Immediately raising the temperature to final compaction temperature. (e) Applying a pressure of 70-350 kg/cm2 until the material is compacted to at least 95% of theoretical density. (f) Relaxing the pressure and immediately expelling the compacted material from the mould, and (g) rapidly cooling the compacted material in an oxygen-free atmos. The refractory material may be oxides, nitrides, borides, silicides, beryllides and/or sulphides, or these substances bonded to metals; e.g., carbides of W, Si, Ta, and/or Ti, and Al2O3, bonded to Co, Ni or Ni/Mo. |
