Effect of dopant content on microstructure and properties of Si-Al-K doped molybdenum

The effect of aluminum, potassium and silicon （AKS） content on the high-temperature properties and microstructure of molybdenum powder, sintering product and fabricated wires were studied. The molybdenum powder was produced firstly by reduction of molybdenum oxide which is doped with K2SiO3 and AI（NO3）3·9H2O. Then doped molybdenum powder was cold pressed into cylindrical compact with diameter of 17 mm, and sintered in induction furnace. The microstructure of molybdenum ingots was examined by transmission electron microscopy. The results show found that the doped elements form non-crystalline phase and distribute along the interface of Mo, thus inhibit the grain growth of Mo. Finally, the sintered Mo was drawn into wires with a diameter of 0.70 mm. The formed non-crystalline particles are changed into row of fine particle during the drawing process.