Aviation and nuclear industry
Due to its excellent heat resistance and high temperature mechanical properties, molybdenum alloy can be used as flame guide and combustion chamber of aircraft engine, throat, nozzle and valve of liquid rocket engine of aerospace vehicle, end of reentry vehicle, skin, wing and guide plate of satellite and spaceship, and protective coating material. Molybdenum has low thermal expansion coefficient and good thermal conductivity, and can be used under strong solar radiation The antenna made of metal molybdenum mesh can keep its parabolic shape, and it is lighter than graphite composite antenna. The cruise missile uses molybdenum coating material as turbine rotor. It works at 1300 ℃ and its speed can reach 40000-60000 rpm. It has shown good effect.
Molybdenum has small neutron absorption cross section, good strength, good stability to nuclear fuel and good corrosion resistance to liquid metal. It can be used as protective sheet of converter armor element in nuclear fusion reactor. Mo-Re alloy can be used in the thermal ion energy converter, heater, reflector and other wire or sheet components of space nuclear reactor.
Molybdenum alloy and other molybdenum is a kind of high-efficiency and multi-functional alloying element. It not only plays a unique role in steel, but also can form excellent alloy with a variety of non-ferrous metals.
The addition of Ti, Zr and C oxides or carbides to Mo results in the formation of dispersion strengthened alloy TZM. Apart from being used in aerospace and nuclear industry, TZM alloy can also be used as X-ray rotary anode parts, die casting dies and extrusion dies. When extruding copper base alloy, its operating temperature can be 870-1200 ℃. TZM alloy is also very suitable for stainless steel hot piercing plug. The inner wall of perforated steel pipe has good quality and long service life. The TEM alloy with a small amount of rare earth elements has a higher recrystallization temperature, and the ductility during recrystallization is five times higher than that of ordinary molybdenum. It also has a good application prospect.
Molybdenum alloy containing titanium, zirconium and carbon (mt-104), molybdenum alloy containing hafnium and carbon (HCM) and molybdenum alloy containing tungsten, hafnium and carbon (HMW) have high strength, which can be processed into bars, plates, forging billets and other products. Mo-30w is a solid solution alloy with melting point above 2800 ℃. It can be used as molten metal pump valve and shaft, nuclear fuel purification and electroplating equipment pipeline, stirring shaft and impeller pump in zinc smelting. When a certain amount of molybdenum is added into the tungsten high specific gravity alloy (90w-7ni-3fe), its strength and hardness increase with the content of molybdenum, but its ductility decreases continuously, which can greatly improve its performance as a weapon material for armor piercing projectiles.
Molybdenum carbide (Mo2C) and tungsten carbide (WC) are mixed, and appropriate lanthanum powder is added to sinter the hard material. After coarse crushing, a certain amount of nickel is added. The molybdenum carbide based hard alloy with good bonding phase distribution, compactness and refinement can be obtained by using the usual production method of hard alloy. The complex molybdenum tungsten carbide based cemented carbides can also be formed when CO or Ni is used as the bonding phase. Molybdenum carbide can also be added to cermets to improve their properties.
