Does the Cryogenic Process makes the metal harder, and therefore more brittle?
Although cryogenic processing makes metals (and other materials) more wear resistant, it rarely increases the hardness any significant amount. The wear resistance comes from a refined crystal structure and the transformation of retained Austenite into Martensite*, not an increase in hardness. Most items are post-tempered after cryogenic treatment to ensure they are not more brittle after processing.
