Rhodium is a chemical element with the symbol Re and an atomic order of 75. Rhodium is a silvery white heavy metal that belongs to the sixth cycle transition metal in the periodic table. It is one of the rarest elements in the Earth's crust and one of the emtals with highest melting and boiling points.
Rhodium is expensive, and alloys containing Rhodium are used in applications. Among them, tungsten rhenium and molybdenum rhodium alloys are the most widely used. The tungsten-rhenium alloy contains 10% to 26% rhodium, and the rhodium content in the molybdenum-rhodium alloy is 11% to 50%. In addition, there are W-33.3Mo-33.3Re, Mo-Re-Hf-Zr, Mo-Re-Hf-V alloys, and the latter two alloys have higher strength. Tungsten-rhenium and molybdenum-rhodium alloys have good high-temperature strength and plasticity, and can be processed into plates, sheets, wires, rods, high-temperature structural parts for aerospace, elastic components, electronic components, etc., and can also be used to manufacture heating elements, workpieces, bulbs, X-ray instruments and medical devices. W-Re-ThO2 alloy can be used as a high-temperature heating workpiece. Tungsten-rhenium and molybdenum-rhodium alloy contacts have high resistance to thermal corrosion and high-temperature conductivity, which can improve the service life and reliability of power supply equipment.