| The benefit of cyro treating steels is completion of the austenite (soft phase) to martensite (hard phase) transformation. This is where cryo treated parts get their improved wear and fatigue properties. Cryo treating by itself will not relieve residual stresses or crystal structure imprefections (dislocations). To reduce the dislocation density requires atomic diffusion. At cryo tempreatures there is not enough energy for dislocation diffusion. Typically cryo treating is followed by a temper at a few hundered degrees F. At this elevated temperature there is enough energy for dislocations to diffuse, reducing residual stresses. IMO cryo treating is typically misunderstood, therefore, it becomes a mythical, wonder process.
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