The product obtained by this method has uniform density and high intrinsic quality, and it does not need to carry out heat treatment processing such as cutting or low temperature sintering, thus greatly improving the product yield and reducing energy consumption.
The preparation method of a kind of tantalum and tantalum alloy bar, its special is that includes the following steps: will make good tantalum or tantalum alloy powder, loaded tubular rubber bag, knead made type, seal, put in cold isostatic pressing machine, through pressure, pressure, pressure relief, complete cold isostatic pressing molding, mold release, obtain compact tantalum rod; The round rod sintered billet was obtained by controlling the sintering temperature of 2100 ~ 2800°C and holding temperature for 3 ~ 20 hours by indirect vacuum heating.
It takes 5 ~ 20 hours to gradually heat up to the sintering temperature, and the vacuum is not less than 1.33mpa, while the sintering temperature is controlled at 2200 ~ 2400°C.
Firstly, it takes 1 hour to rise to 300 ~ 500°C for 10-30min, then it takes 0.5 hours to rise to 600 ~ 800°C for 10-30min, and then it takes 1 hour to rise to 1200 ~ 1400°C for 60-120min. Finally, keep the temperature at 2200 ~ 2400°C for 60 ~ 180min after 1 hours.
High vacuum indirect heating furnace or vacuum induction furnace is used for indirect heating.
The cross section of the tubular rubber sheath is round.
First the purity is more than 99.9% of tantalum and tantalum alloy powders into the inner diameter is 32 mm rubber bag, concrete is to say good tantalum or tantalum alloy powders with a funnel slowly into the rubber bag set inside, control the filling quantity is 6 kg, then the rubber bag openings into the rubber plug, and other rubber after discharge air in the bag with wire rubber plug part article bundle tight as a blank, Then the blank is kneaded evenly and clamped with two splints. The splint and the blank are fixed together with the rubber band, and then placed in the cold isostatic pressing machine.
