Preparation and properties of high-strength molybdenum alloy sheets doped with Al_2O_3 particles

摘要

The pure molybdenum sheet and the Al_2 O_3-doped molybdenum alloy sheets were prepared by the hydrothermal method and a subsequent powder metallurgy process. The effects of Al_2 O_3 particles addition on the recrystallization temperature, microstructures and properties of the Mo sheets were investigated as the focus. The Al_2 O_3-doped Mo sheets have greater strength than the pure Mo sheet, and the 0.50 wt% Al_2 O_3-doped Mo sheet has the best performance. For the unannealed specimens, the strength increases with the increase in Al_2 O_3 content.Compared with that of pure Mo sheet, the strength of0.50 wt% Al_2 O_3-doped Mo sheet increases by 72%, 54%,73% and 76%, respectively, when annealed at 1000,1100,1200 and 1300 ℃, which is a very obvious reinforcement effect. When lower than 1100 ℃, the elongation of the pure Mo sheet is the best. However, when the annealing temperature is equal to or greater than 1100 ℃,the 0.50 wt% Al_2 O_3-doped Mo sheet obtains the best elongation. Moreover, the Al_2 O_3 addition can greatly improve the recrystallization temperature of molybdenum sheets; for example, the recrystallization temperature of the0.50 wt% Al_2 O_3-doped Mo sheet increases by 200 ℃ at least than that of the pure Mo sheet. Lastly, the strengthening mechanism was discussed.