The melting point of tungsten-rhenium thermocouple wire ranges from 3,120 to 3,360℃, and its maximum working temperature may reach 2,800℃. It is the most fire-resistant metallic thermocouple, and it has many advantages such as perfect temperature-electromotance linear relationship, high sensitivity, reliable thermostability, and low price. Therefore, tungsten-rhenium thermocouple is already extensively applied in the industries like metallurgy, building materials, aerospace, aviation and nuclear energy.