Typically occurring between the quenching and tempering processes, deep and cryogenic freezing helps to eliminate the presence of retained austenite in metal, meaning austenite not transformed during the quenching process. Bringing such parts to extremely low temperatures (around -100 to -120 degrees Fahrenheit) in deep freezes helps to transform the remaining austenite, which can contribute to part wear and fatigue. Cryogenic deep freezes occur at far lower temperatures than standard deep freezes (around -300 degrees Fahrenheit) and liquid nitrogen is added to the process. This process is sometimes used with ultra-high-precision parts such as gun barrels, dies and gears.
In some highly specialized applications, especially for parts performing precision functions, there is also concern about volume transformations over time. Such changes in the dimensions of a part, even very small ones, can easily render it useless in performing its intended function. Especially with components required to be tough and wear-resistant, it’s critically important they be treated in a way that allows them to retain their shape over time. Luckily, deep and cryogenic freezes can prevent volume changes in parts even for long after they’ve been treated.
And because Paulo customers can trust our purpose-built Production Information and Customer Service system (PICS), they know to expect consistency from start to finish. From the time your weight calculations are entered into our system, through process control, Paulo produces consistent results.