GB/T 4189-1984

GB/T 4189-1984 specifies the technical requirements, test methods, inspection rules, and packaging for doped tungsten bars, which are tungsten materials containing trace amounts of doping elements such as potassium, silicon, or aluminum. This standard is applied in the metallurgical industry for the production and quality control of tungsten bars used as raw materials for manufacturing high-performance tungsten wires, electrodes, and other components in lighting, electronics, and high-temperature applications. It ensures consistent material properties like recrystallization temperature and ductility, critical for products like incandescent lamp filaments and welding electrodes.