TZM alloy material was prepared by spray drying
TZM is the best molybdenum alloy, is currently a large amount, a wide range of uses of molybdenum alloy. TZM molybdenum alloy has the advantages of high temperature strength, heat erosion, wear resistance, low temperature mechanical properties and good welding performance, high temperature hardness and stiffness, good thermal and electrical conductivity, etc., can be used for high temperature structural parts with a working temperature of about 1400℃. It is widely used in the chemical industry, petroleum industry, metallurgical industry and metal processing industry, aerospace industry and nuclear energy technology, such as die casting mold materials, rocket nozzle throat liner, valve body in special engines, nozzle in combustion chamber, nozzle, gas conduit, thermionic energy converter in the jacket material.
The traditional methods for preparing TZM alloy include melting and powder metallurgy. The smelting method is to melt pure molybdenum and a certain amount of Ti, Zr and other elements under the protection of vacuum or hydrogen, and then use casting or machining to obtain TZM bars or billets; The principle of powder metallurgy is to mix high purity molybdenum powder with titanium compound, zirconium compound and graphite powder evenly according to proportion after cold isostatic pressing forming, and then sintering at high temperature in a protective atmosphere to obtain TZM billet. The smelting method has long process, large process loss of raw and auxiliary materials, low yield and high cost, so it is not conducive to popularization and application. The powder metallurgy method has made up for the above shortcomings and has become the most widely used TZM alloy preparation method so far.
At present, the main process of preparing TZM alloy by powder metallurgy is high purity molybdenum powder mixed with TiH2 powder, ZrH2 powder and graphite powder in proportion to press forming, and then sintered at high temperature under vacuum or protective atmosphere to obtain TZM billet. TZM alloy prepared by this method has the problems of difficult to control carbon content and high oxygen content.
Firstly, TZM alloy powder was prepared by spray drying method. The content of carbon and oxygen elements in the alloy was reasonably adjusted by adding an organic binder. With the help of solid-liquid doping and mechanical stirring, the alloy composition was more uniform. The change trend of alloying elements in sintering process is controlled to achieve the purpose of reducing oxygen content.
