| 摘要 |
PURPOSE:To manufacture a molding having high rigidity by explosion-press molding polyacrylonitrile powder filled to have specific bulk density. CONSTITUTION:Polyacrylonitrile powder (having 20mum of mean diameter) having 70,000 of mean molecular weight is preliminarily compressed by a piston press (70MPa). This is then charged in a metal vessel 5 having 2mm. thick and 30mm. in inner diameter, evacuated via an exhaust pipe 7 by a vacuum pump to 1- 10mPa, and the pipe 7 is fusion-disconnected in this state. The bulk density of the powder 4 is at least value of 0.87 times of the true density. Then, the prescribed current is flowed to an electric detonator 1 disposed at the top of the powder 4 to explode powder 3. In this case, clay lump 2 at the top of the vessel alleviates the impact pressure applied from above to prevent the damage of the vessel. Thus, a molding having high rigidity can be molded. |
