Application of molybdenum and molybdenum alloy
Electronic power equipment manufacturing industry is the main application field of molybdenum and molybdenum alloy materials. It includes filament, lighting and electronic tube components, special printed circuit board coating, microwave devices, medical electronic and electrical equipment, internal components of light tube (such as rotating target, bracket and heat insulation screen), X-ray flaw detector, low thermal expansion material for integrated circuit components, buffer for power supply and heat dissipation, silicon substrate for replacing some parts, and nickel plating for rectifier Heat treated molybdenum sheets of copper or germanium (Rh) and heat sinks for pressing and sintering of small electronic components. Molybdenum (Mo) can also form Cu / Mo / Cu (CMC) composites with copper (Cu). Cu can improve the thermal expansion properties of the composites, so that it can better match the ceramic matrix. This kind of CMC component has high elastic modulus, so it can reduce its vibration fault.
The main application areas of molybdenum and molybdenum alloy in material processing industry are as follows.
1.1 For hot working dies
The Aerospace Department mainly uses molybdenum alloy to make dies and high temperature forging engine parts. The main application materials are active metal carbide strengthening molybdenum, optional element strengthening molybdenum and mechanical dispersion two-phase strengthening molybdenum alloys. Molybdenum alloy reinforced by active metal carbide has good high temperature strength and high thermal conductivity, so it is mainly used in hot working die industry. It is because of its high thermal conductivity and low thermal expansion that molybdenum becomes the first choice of heat shock resistant materials.
1.2 For molten metal processing
The hot cracking problem of processing materials is restrained by molybdenum used in aluminum casting plant, that is, TZM (Ti · Co · Mo) is usually used in the hot cracking parts of processed materials.
Alloy core and mandrel (rod). The use of TZM and MHC alloy can also improve the rapid solidification ability of processing equipment. Tungsten molybdenum alloy has the same corrosion resistance, which can significantly reduce the production cost. Therefore, mo-25% w and mo-30% W alloy materials which are suitable for application in impeller, pump set and molten zinc pipe system have been developed.
1.3 Thermal spray treatment
Molybdenum can be used to heat spray the piston ring. The method is to mix molybdenum powder with the binder containing nickel (Ni) and chromium (CR), and then spray the mixture on the piston by plasma. The coating can be pure molybdenum or molybdenum alloy mixed powder. It is wear-resistant and corrosion-resistant, so it is suitable for paper industry application. Moreover, molybdenum powder can be mixed with different contents of nickel, chromium, boron and silicon powder In addition, molybdenum and molybdenum alloy mixed powder can also be used for plasma nozzle to compact prealloyed powder with different quality, better wear resistance and corrosion resistance
1.4 For chemical treatment
For example, molybdenum and molybdenum alloys are mostly used as hip equipment materials, heating elements, sleeves and supports: molybdenum clamps and sintered molybdenum boats are widely used in ceramics; oxide ceramic products are almost produced in electronic industry In addition, due to the compatibility of molybdenum with hot gas and high temperature strength, it can be used in aerospace and national defense industry. However, the poor oxidation resistance of molybdenum limits its application, Molybdenum is mainly used as rocket and active gas valve with high speed and good performance.
