Emulsifiable oils

[Mike Arsenault]

I've noticed a thread or two regarding an oil and water heat treatment, and was wondering:

Would an emulsifiable oil (such as Dromus B, a machine tool cutting fluid) be useful for such an endeavor? Perhaps one could make the mixture as thin or as thick as desired, changing the quenching properties relative to the required task.

 

[Stacy E. Apelt - Bladesmith]

Viscosity (Thin and thick) is not the primary issue of a quenchant. The rate of thermal absorption is what determines the quench speed.This is affected by the vapor point,bath volume,bath temperature,and conditions that control the amount of heat that can be absorbed (agitation,spray,etc.)
There are water based quenchants and polymer quenchants out there. I don't know of any knife makers that use them. They are more of an industrial chemical to deal with vapors and flammability issues.
All that aside, you could do a series of tests on quenching pieces of 1/8X1X6" bars in 1095 or 1084. That should tell you a lot about the oil/water quenchant being fast enough.
Final note - Most soluble oil cutting fluids are created to prevent rust, cool,and lubricate. The cooling is mostly a function of flow rate not quench speed.The main chemical nature is in the rust prevention and lubrication ends.
Stacy