Preparation and properties of high-strength molybdenum alloy sheets doped with Al2O3 particles

Abstract

The pure molybdenum sheet and the Al2O3-doped molybdenum alloy sheets were prepared by the hydrothermal method and a subsequent powder metallurgy process. The effects of Al2O3 particles addition on the recrystallization temperature, microstructures and properties of the Mo sheets were investigated as the focus. The Al2O3-doped Mo sheets have greater strength than the pure Mo sheet, and the 0.50 wt% Al2O3-doped Mo sheet has the best performance. For the unannealed specimens, the strength increases with the increase in Al2O3 content. Compared with that of pure Mo sheet, the strength of 0.50 wt% Al2O3-doped Mo sheet increases by 72 %, 54 %, 73 % and 76 %, respectively, when annealed at 1000, 1100, 1200 and 1300 °C, which is a very obvious reinforcement effect. When lower than 1100 °C, the elongation of the pure Mo sheet is the best. However, when the annealing temperature is equal to or greater than 1100 °C, the 0.50 wt% Al2O3-doped Mo sheet obtains the best elongation. Moreover, the Al2O3 addition can greatly improve the recrystallization temperature of molybdenum sheets; for example, the recrystallization temperature of the 0.50 wt% Al2O3-doped Mo sheet increases by 200 °C at least than that of the pure Mo sheet. Lastly, the strengthening mechanism was discussed.