TZM Alloy and Molybdenum Performance Comparison

Observing sintered TZM alloy and molybdenum microstructure found, TZM alloy sintered grains is about 30um, while pure molybdenum sintered grains is about 40um. This is because Ti and Zr and other the trace element in TZM alloy are conducive to refine the grain, so TZM alloy grains compare to molybdenum’s is smaller.

TZM alloy room temperature property is significantly higher than molybdenum’s, but not as good as its elongation. At 1200 ℃ high temperature, the tensile strength of molybdenum has dropped significantly, while the tensile strength of the TZM alloy remained at a high level. This is mainly because TZM alloy second phase impede dislocation movement, resulting in a significant second phase strengthening and solid solution strengthening, improved strength of the alloy. Meanwhile, dispersed second phase having pinning effect on dislocation will reduce the deformation resistance of the alloy, resulting in ductility property significantly reduced. The molybdenum at 1200 ℃ high temperature occurs recrystallization, so the strength of it is not as good as TZM alloy, while plastic is better than TZM alloy.

Observing tensile fracture morphology of TZM alloy and molybdenum at room temperature and 1200℃ high temperatures found, at room temperature, TZM alloy fracture morphology is cleavage fracture, so the elongation is poor. At 1200 ℃ high temperature, TZM alloy fracture morphology has changed. There are has many dimples, and the fracture morphology is dimples-cleavage fracture, so the elongation get some improvement, higher than the room temperature elongation. Molybdenum high-temperature tensile fracture morphology shows ridge pattern humanoid, with a clear dimples, so it has good elongation.

TZM alloy starting recrystallization temperature is about 1350 ℃, the end recrystallization temperature is about 1700 ℃. Molybdenum starting recrystallization temperature is about 850 ℃, and the end recrystallization temperature is about 1250 ℃.