TZM Alloy Cogging-down

Firstly, TZM alloy billet temperature should not be too high or too low and a reasonable amount of cogging-down process not only reduces the deformation resistance, and will reduce the chance of breakage of the alloy.

In addition, the cogging reduction can reflect the deformation parameters of TZM alloy, which determines the microstructure and properties of the alloy. Cogging-down reduction of TZM alloy is similar to molybdenum which is usually used 25%~ 30% deformations amount. This is because a large amount of deformation, not only it can help the TZM alloy billet has uniform deformation, so that in subsequent processing, there will not produce delamination, burst and other defects. But also it can make the TZM alloy obturator, porosity, and other crushing closure.

On the other hand, due to the quality of alloy billet will affect the subsequent processing steps, so often before the billet into the rolls, which fall under for two in the instruments on stage to shake off most of the scale, and then quickly push into a roll. Meanwhile, TZM alloy billet in the heating stage to have hydrogen protection system to prevent oxidation of the alloy. 

Because the alloy is easily oxidized in the air, and the resulting oxide not only be pressed into the molybdenum rolling, forming pits, affecting the surface quality and smooth TZM alloy blanks for subsequent rolling process, and will significantly reduce the friction, thereby undermining the bite condition and stable rolling conditions, slippage phenomenon.