Molybdenum News Center

Using Powder Metallurgy Method for TZM Alloy Plate Manufacturing

TZM alloy is the most used widely and the best performance molybdenum alloy. TZM alloy has good high temperature strength, creep resistance and higher recrystallization temperature, so it is often made of nozzle, piercing point, mold, heat shields and high-power ceramic tube gates, widely used in industry, military and aerospace fields. TZM alloy production methods are melting and powder metallurgy. Currently most of manufacturers choose to use powder metallurgy method, mainly because it doesn’t need have consumable arc furnace, large presses and high-temperature furnace and other large equipment, and the process is simpler. Besides, using powder metallurgy for TZM alloy plate manufacturing the production cycle is short and energy consumption is low, having high productivity. In addition, the alloy which produced by powder metallurgy has similar properties with smelting method produced alloy. To obtain good system performance alloy plate should improve alloy’s recrystallization temperature and ductility, and reduce plastic-brittle transition temperature, so in the process of rolling should roll in changed directions and process intermediate heat treatment, making the alloy performance has improved. TZM alloy plate produce by powder metallurgy method and the production processes are as following:

1. Mixing 0.45% Ti, 0.08% Zr, 0.01% C and graphite powder with Mo for 6 hours is good for full mixing.
2. Using cold isostatic to press the mixed powder at 150MPa pressure obtain pressed blank.
3. Under the protection of hydrogen, the pressed blank is placed in sintering furnace at 2100 ℃ for 4 hours heat preservation and then to sinter to get TZM alloy blank.
4. Roll the 30mm blank at 1350℃, making the slab thickness to become 4.5mm, and the deformation is 83%. Then at 700 ~ 750 ℃, the slab is rolled to 1.2mm, and the total deformation is 95%.
5. Anneal at 900 ℃to eliminate stress, then at 600 ~ 700 ℃ longitudinal rolling to obtain 0.7mm.
6. After annealing at 850 ℃ to eliminate stress, then longitudinal cold rolling at 200 ~ 300 ℃ obtain 0.5mm alloy plate, and the total deformation is 98%.

• < Prev
• Next >