Tungsten, with symbol W and atomic number 74, is a whitish-gray metal that is simultaneously hard and brittle. It typically exists in the yellow tungstic oxide, WO3. Tungsten is commonly formed by sintering, and in its pure state retains its hardness yet can be malleable by forging, drawing, or extruding. Of all metals, tungsten has the highest melting point (3,422°C/6,192°F), lowest vapor pressure (at temperatures above 1,650 °C/3,000°F), highest tensile strength, as well as the lowest coefficient of thermal expansion of any pure metal. It also has one of the higher densities at 19.3 g/cc (0.70 lbs/in3). Due to its many unique properties, tungsten plates and sheets are widely used to fabricate parts for commercial, industrial, and military applications. Tungsten alloy and pure tungsten-made electrodes/wires also have a wide variety of applications, mostly utilized in the electrical, electronic, heating, lighting, and welding industries. Tungsten is also utilized to produce heavy metal alloys for armaments, heat sinks, radiation shielding, and weights/counterweights.
Molybdenum, with symbol Mo and atomic number 42, has the 6th highest melting point at 2,623 °C/ 4,753 °F, ranked after tantalum, osmium, rhenium, tungsten, and carbon. Due to its stability and strength at elevated temperatures, molybdenum is the material of choice for many high-temperature components. Other important properties include high thermal conductivity, high electrical conductivity, low coefficient of thermal expansion, resistance to attack by molten metal, compatibility with most glass compositions, thermal shock resistance, high stiffness, resistance to abrasion and wear, and strong bond with glass used in electronic devices. About 86% of molybdenum produced is used in metallurgical applications such as high strength alloys and superalloy, with the rest of molybdenum used as part materials for lighting, medical equipment, materials processing equipment, thermal spray coatings, and aerospace and defense components.
Tungsten Heavy Alloys (WHA)
C&L supplies various grades of W-Ni-Cu and W-Ni-Fe, commonly referred to as tungsten heavy alloys. Pure tungsten is not suitable for mass volume production for density-driven applications due to its brittleness, high cost, and difficulty to shape and process without thermomechanical processing. Tungsten heavy alloy (WHA) is created by taking principally pure tungsten (90-98 weight % range of tungsten content) and combining it with a binder containing transition metals and dissolved tungsten, often W-Ni-Cu and W-Ni-Fe, resulting in a material that provides size and shape flexibility while still preserving pure tungsten’s full density.
Despite alloy characteristics that can vary with Ni/Fe or Ni/Cu ratios, our WHA offer significantly better machining size, shape flexibility, and lower fabrication costs. WHA is a more practical and ideal material for density-driven applications such as balance weights (crankshaft counter weights, balance shafts in racing cars or flight control surfaces on aircraft, vibration damping), radiation shielding, wearable applications, and high precision optical instruments.