METHOD OF HOT PRESSING POWDER BODIES

摘要

1441330 Isostatic hot pressing in glass capsules ALLMANNA SVENSKA ELEKTRISKA AB 20 Sept 1973 [16 Nov 1972] 44159/73 Heading C7D A method of isostatic hot pressing in which a powder body or bodies is/are charged into a glass capsule which has a larger internal volume and after evacuating and sealing the capsule is heated to at least its softening temperature and isostatically pressed. The powder may be isostatically pressed and optionally sintered prior to charging into the glass capsule and when several bodies are charged into the capsule they are separated by glass or metal spacers. Alternatively the capsule may be heated and locally pinched during charging in order to separate the bodies. Cutting elements for circular saw blades may be pressed from a mixture of 10-50% vol. diamonds and a bronze containing 91% Cu, 9% Sn and max. 0À3% P or a bronze containing 67% Cu, 31% Ni, 1% Mn, 0À7% Fe. The compacted powder mixture is preferably sintered at 700‹C in H 2 or vacuum prior to packing in a glass capsule which is then evacuated to 10-3 to 10-4 torr and hot pressed at 750‹C and up to 550 bor. Gas turbine blades can also be produced by the process.