Frequently Asked Questions

Find answers to the most asked questions about your purchase, order or shipping

Cryogenic Treatments

This is the opposite of heat treating and it’s done to a part that is generally finished, such as a complete axle shaft. The part is cooled by normal refrigeration to about 100 degrees below zero, Fahrenheit, then further cooled by nitrogen gas to about 300 degrees below zero. The timing and length of the treatment is precisely controlled according to the material and the end result desired and, after cooling, the part is heated to over 300 degrees then allowed to cool naturally in the air. The advantages are that it relieves internal stress in parts and tightens the grain structure. The treated part is much more fatigue resistant, though only very slightly stronger. Dimensional changes are usually miniscule or non-existent.

Normalized

Steel that is reheated to its critical range temperature, then cooled in still, open air. The process makes the piece uniform in strength and relieves stresses. Without heat treatment, formed metal will try to go back to its original shape.

DRIVELINE | AXLES - What kind of heat-treating does Yukon perform on its chromoly axles?

The goal is to alter the properties of the metal on a molecular level, producing a tighter grain structure that changes the hardness, strength, toughness, ductility, and elasticity of the material in a beneficial way.

Induction hardening is the method Yukon uses on its entire line of performance axles. The process starts with an axle shaft that has likely been fully machined with splines etc. The shaft is heated with an induction coil to a predetermined temperature usually between 1,550- and 1,600-degrees Fahrenheit then quenched. Quenching is basically dousing the part with water or dropping it in an oil bath to quickly cool it. Yukon’s quality assurance staff will test axles from random production batches to ensure they receive proper heat treating and measure up dimensionally to engineering blueprints.