Both tungsten and rhenium are high-melting metals and are widely used in high-temperature fields. But they also have disadvantages, pure tungsten is brittle, recrystallization temperature is very low; Rhenium is poorly processed and expensive. Their applications are greatly restricted. Made components with the rhenium tungsten rhenium tungsten alloy, the alloy overcomes the drawback of pure tungsten and rhenium, has many excellent properties, such as high melting point, high strength, high hardness, high plasticity, high resistivity, high thermoelectric potential value of the recrystallization temperature, high, low vapor pressure, low electron work function and low plastic a brittle transition temperature, etc., at the same time they also have excellent resistance to "water cycle" response performance, the price is lower than the pure rhenium 75 ~ 95%.
So the tungsten-rhenium alloy in modern electronic technology, thermal control, nuclear technology and space technology, temperature field, instruments and meters, electrical appliances and other sophisticated science and technology department has been widely used. Especially the tungsten-rhenium alloy wire matching thermocouple, has the very high thermoelectric potential and sensitivity, and temperature measuring range, fast response, good corrosion resistance, is temperature measurement in the field of good thermal sensing materials. It is an irresistible trend to replace platinum rhodium thermocouple with tungsten-rhenium thermocouple.
Many contact materials are commonly used in electric switches, such as automobile horn contact and ignition contact, voltage regulator contact, telephone contact and various electric switch contacts. At work, all the contact friction and spark erosion and high frequency of contact with each other etc., thus, making contact materials shall meet the following requirements: (1) the material of the small contact resistance, (2) the volt-ampere characteristics of arc small, rate of erosion was small, and so on.
Metals that can be used as contact materials include: copper, silver, platinum, rhodium, iridium, tungsten, molybdenum, rhenium, tungsten-cu alloy, w-silver alloy, w-qin alloy and high-specific alloy. At present, tungsten, molybdenum, rhenium and their alloys have been widely used in automobile horn contacts and igniter contacts. Rhenium tungsten alloy is used in contact materials and has been developed in recent years. It can be compared with platinum, iridium, rhodium and other precious metals.
Various components of tungsten-rhenium alloy wire can be paired into tungsten-rhenium thermocouple. Tungsten-rhenium thermocouple is widely used in industrial practice, including:, doping, and iso-rhenium thermocouple. They have a high thermoelectric potential value and high sensitivity, thermoelectric potential - good corresponding relation between linear temperature, high temperature (2800 ℃), high precision (the deviation of plus or minus 0.25% allowed t, plus or minus 0.5% and + 1% t three t).
Rhenium tungsten thermocouple is mainly used for temperature measurement in vacuum, reducing atmosphere and inert atmosphere. Some special anti-oxidation measures are adopted in the oxidation atmosphere, which can replace the temperature measurement of platinum rhodium thermocouple. Rhenium tungsten thermocouple is 12 ~ 18 times lower than that of single platinum germanium thermocouple, and w-rhenium thermocouple has obvious economic benefit in replacing platinum rhodium thermocouple in temperature measurement, which has attracted more and more attention.
