| 摘要 |
PURPOSE:To prevent the formation of parts differing in working ratio by rotary forging and to enable the uniform working of ingots, by forming the sectional shapes of dies for pressure molding of hard to melt metallic powder in such a way that green compacts of which the sectional shape is approximate to a circular shape having the number of sides larger than the number of sides of a rectangular shape. CONSTITUTION:Powder 8 of W, Mo and their alloy is packed between the 1st member constituted by assembling side dies 6, 6' and bottom dies 7 and a movable punch 5, and is subjected to pressure molding, whereby a green compact is obtained. For example, the punch 5 in this case has three sides AB, AH, HG, and the die 7 has three sides CD, DE, EF. The green compact of an octagonal shape wherein the vertcal anqles of the square are eliminated is obtained. The genertion of cracks is reduced by removing corners. |
