The nature of molybdenum
Of molybdenum and tungsten is very similar in nature, its boiling point, and outstanding electrical conductivity, thermal expansion coefficient, more easily processed than tungsten.
Molybdenum metal thermal conductivity [135 W / (m · ON)] and specific heat [0.276 kJ / (kg · f open)] was the best match, making it a thermal shock and thermal fatigue of natural selection. Its melting point is 2620 ℃, inferior tungsten, tantalum, but the density is much lower than, so its specific strength (strength / density) than tungsten, tantalum and other metals, in the weight requirements extremely critical applications, more active. Molybdenum at 1200 ℃ still high strength.
The main disadvantage of Molybdenum tube high temperature oxidation resistance is poor (above 600 ℃ rapid oxidation) and poor ductility at room temperature. As weaknesses, problems for multi-use high-temperature oxidation coating (such as paint MoSi2, nickel, chrome, etc.) way to control; pair of plastic which is usually too poor to say the lack of low-temperature embrittlement, and processing people through strengthening alloy carbides to achieve enhanced and other measures to solve.
tungsten carbide plate (W), rhenium (Re), tantalum (Ta), titanium (Ti) and zirconium (Zr), etc. are common solid solution strengthening element. Tungsten is the primary solid solution strengthening elements molybdenum, rhenium can be extended to brittle transition temperature dropped -200 ℃. Formed by them industrial molybdenum alloy Table 1-1. Which constitute the lanthanum molybdenum lanthanum alloy shows very prominent and high temperature creep deformation capacity, which at high temperatures, this feature is particularly evident.
Applications
Vacuum furnaces, glass melting, electronic devices, heat sink
Thermal processing tools, stoves installed appliances
Hot work toolMolten zinc treatment, sputtering target
Traveling wave tubes, rocket boostersSintering boat
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