Quenching Process

Hot metal parts like gears, are quenched by water, air, oil, or liquid polymers for obtaining a specific hardness or mechanical properties. Quenching process is typically by cooling at a comparatively high rate. This is done to avoid problems like internal microstructure that are not desired, ensuring uniform mechanical property, minimal residual stress, warpage avoidance.

In quenching process it is inconsequential as which type of quenchant is being put to use. Cooling typically takes place in three distinct stages, each with a distinct characteristics:

• Vapour phase
• Boiling phase
• Convection phase

Limitations of Quenching
In Quenching of gears there can be certain disadvantages that can play spoil sport. For example in cases of quenching where there is plugged coolant nozzles, this invariably leads to improper quenching on one part of the gears.

Another example can be given of quenching oil an insensitive handling of which can lead to fire. Press Quenching
To improve upon the limitations imposed upon by Quenching methods there evolved a technique called Press quenching. This is a very unique technique. It involves the physical restraint of distortion prone Gear parts, in an ongoing quenching operation that requires close-tolerance fixtures. It is ideally used for minimizing distortion in automotive transmission ring gears.