As the raw material of C103 alloy, niobium-tantalum-tungsten alloy bar has strict requirements for Ta, W and gas impurities C and O, as well as sampling at the end, which increases the difficulty of production. In this paper, the process of producing Nb-Ta-W alloy strip by powder metallurgy was studied. The method of uniform distribution of Ta and W was found out, and the reasonable process scheme was put forward.
C103 alloy is a kind of high strength and heat resistant material. It is based on Nb, Ta, W to add elements. The alloy was prepared by bombarding strip as raw material. Therefore, there are strict requirements for the uniform distribution of Ta and W in nb-ta-w alloy bars and the content of C and O in gas impurities (see table 1). In particular, the sampling site is different from the first Nb - end sampling. This increases the difficulty of production control. In order to master the control laws of C, O, Ta and W, and to find out the process parameters, the author carried out the process research, and put forward the reasonable process plan of powder metallurgy method to get the alloy bar.
This experiment takes metal powder as raw material, adopts powder metallurgy method, adds Ta powder to Nb in two different forms and mixes it with W powder, and then forms it by cold pressing. The formed blank is loaded into a graphite crucible and sintered in a vacuum carbon tube reduction furnace. Sintering strip sampling analysis, grinding head, get the product.
The addition of elements Ta and W to the nb-ta-w alloy strip is small, and the density of Ta, W and Nb varies greatly, so segregation is easy to occur during mixing. In what form can they be added to Nb to reduce the influence of density on Ta and W uniform distribution. It can be seen from table 4 that the mixture of nb-ta intermediate alloy powder and W, the uniform distribution of Ta and W alloy strip obtained is better than that of the alloy strip prepared directly with Ta powder, W powder and Nb powder.
