Views: 2 Author: Site Editor Publish Time: 2022-04-08 Origin: Site
With the continuous maturity of high and new technologies such as plasma arc and laser, higher requirements are also placed on the properties of cerium tungsten wire. However, due to the difficulty in controlling the uniformity of cerium-tungsten doping and the difficulty in wire drawing, it is difficult to produce filaments with extremely small diameters, which restricts the application and development of cerium-tungsten alloy wires. In order to solve the above deficiencies, some researchers provide a new preparation method, the specific steps are as follows:
(1) Select square monoclinic ammonium paratungstate, and generate blue tungsten oxide after mild reduction, and then dope a certain amount of Al(N03)3 solution, K2SiO3 solution and Co(N03)2 solution;
(2) After mixing, one part is directly reduced, and the other part is reduced in two stages. The raw materials after two reductions should be acid washed for 30-40 hours, and then vacuum dried;
(3) After burning, sieve the mixture, perform the first reduction between 750 °C and 800 °C, and perform the second reduction between 900 °C and 950 °C, and then use isostatic pressing and mechanical steel mold pressing. The billet is formed, and then pre-fired at low temperature, and two high-temperature vertical melting sintering can be carried out in the intermediate frequency induction furnace;
(4) The sintered billet is subjected to multi-machine blanking and spinning, crystallization annealing, recrystallization annealing, stress relief annealing and drawing treatment to obtain tungsten wire products.
Notes for this production method: 1) In step (1), the particle size of ammonium paratungstate is controlled at 30 μm-50 μm; in step (2), the first-stage temperature of the two-stage reduction is 550°C-660°C, and the second-stage temperature is 610°C-810°C ℃, while the vacuum drying temperature is 80℃-120℃; 3) The pre-burning temperature in step (3) is 1100℃-1250℃.
The advantages of this production technology: by adding dopants containing cerium, potassium, cobalt and other elements, the element distribution in the produced tungsten alloy billet can be more uniform, and the ablation performance is better, thereby increasing the seismic performance of the tungsten wire and The product yield is high, and the diameter can be less than 0.39mm.