During the metal forming process, Quench Fluids cool the metal at a controlled rate to produce the required hardness and minimize distortion.

As the hot metal is immersed in a bath of Quench Oil, cooling takes place in three phases:

• The Vapor Barrier Phase, where a vapor layer forms between the hot metals surface and the bulk of the quench fluid
• The Boiling Phase, where rapid cooling occurs
• The Diffusion Phase

When Quench Additives are added to Quench Oils, they fill the important function of collapsing the vapor barriers, thus accelerating the process towards the Boiling and Diffusion phases, and they allow an oil formulation tailored to the hardness requirements of the metals being quenched.