At the proper time and temperature, the crucible is dumped into aerated H2O, a chemical also known as water. This chemical solvent may have some potassium nitrate added, or maybe not. Most practitioners want this quench solvent known as water to be rather cold. The contents of the crucible are typically dumped into the quench as close to the surface as humanly possible, to prevent oxygen from coming in contact with the red hot steel. This little controlled chemical step is done because excess oxygen during that brief instant will cause our desired colors to become dull gray and muted. Of course, dumping the red hot contents into the cold water quench causes a violent reaction where the liquid water is instantly turned to steam. The goal is to keep the carbon based pack in contact with the surface of the steel until the moment it hits the cold water quench. The water is often aerated and/or agitated to attempt to keep the water in contact with the extremely hot steel parts. And the molecular structure of the surface of our carbon infused steel is thusly frozen into a molecular arrangement that causes the pleasing refraction of light that our eyes perceive as Case Hardening Colors. Not seen is the dramatically increased surface hardness...
from keith's post above...shore sounds like a chemical reaction to me...
Last edited by ed good; 08/09/22 12:09 PM.
