Sintered molybdenum and its alloys due to the melting point is too high, large deformation resistance, narrow plastic range, so the heating temperature is cannot too low, otherwise the rolling process can not proceed. When TZM alloy billet heating temperature is higher than 1100 ℃, the alloy is only a little plastic, but when the temperature exceeds 1250 ℃, the alloy plasticity improved significantly. Reasonable cogging-down temperature TZM alloy can not only reduce the deformation resistance in cogging process. Besides, at the large cogging-down pressure, alloy billet fracture does not occur.
The experiment found that the cogging-down temperature selected too high, not only easy to make billet has coarse grains, waste of energy, but also have a negative impact on organizational performance of the finished TZM alloy. The cogging-down temperature is too low, TZM alloy billet easy to crack. Therefore, in selecting the appropriate cogging-down temperature, not only to refer to past experiences, but also consider process control, general TZM alloy billet reasonable cogging-down temperature is at 1400 ℃. At this temperature the alloy none cracking scrapped, and has good performance.
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