Copper 10w3 Rectangle Bar is a copper-tungsten alloy containing around 90% copper and 10% tungsten. This alloy combines the high electrical and thermal conductivity of copper with the strength, wear resistance, and arc erosion resistance provided by the tungsten content. Copper 10w3 rectangular bars find applications in areas like welding electrodes, electrical contacts, and resistance welding components that require good conductivity along with resistance to wear and arcing.