Quench
Quench turns up in 2 fields: heat treating, nonwovens. Here is what it means to the people in each one.
Quench in heat treating
To cool hot metal rapidly in a liquid or gas so that it hardens, or the act of doing so.
Rapid cooling from the austenitizing or solution temperature in water, brine, oil, polymer solution, molten salt or pressurized gas. In steel the goal is to cool faster than the critical rate so austenite becomes martensite; in aluminum and precipitation-hardening alloys it freezes alloying elements in solution. Quench speed is a trade-off: faster means deeper hardening but more distortion and cracking risk.
"Pull the rack and quench, ten seconds max from door open to oil."
Quench in nonwovens
Stream of cooled, conditioned air that solidifies filaments just below the spinneret in spunbond and fiber spinning.
Quench air flows across the filament bundle as it leaves the spinneret, freezing the molten polymer before it is drawn. Its temperature, speed and evenness across the width decide filament diameter, breaks and how even the curtain looks. Warm or uneven quench gives stuck filaments, roping and drips, while overly cold quench makes filaments hard to draw.
"Quench on beam one is running two degrees warm and we're seeing stuck filaments on the operator side."