HEAT TREATMENTS IN GASEOUS NITROGEN: CRYOBOX
There are also heat treatments with liquid nitrogen that gasifies and i are used CRIO BOX: liquid nitrogen is sprayed inside and gasifies, creating a sub-zero and adjustable temperature. This can create rise and fall ramps in temperature, with different times, so that you can give the material being treated a “State of function diagram” of cooling, or even of the heating, and this serves for example to obtain the transformation of the residual austenite in martensite. Martensite gives the steel a higher surface hardness and a longer wear resistance over time, compared to materials not treated in this way. The CRIOBOX substantially it is a large refrigerator, a large container in which a cold atmosphere is generated by means of gasified liquid nitrogen.
This cold atmosphere transfers the frigories to the various artifacts. In the Criobox, nitrogen is used in the gaseous phase with temperatures that can vary from – 100 ° to – 180 ° and the products are immersed in an atmosphere of nitrogen gas; while for the DEWAR, that is the small tank, nitrogen is used in the liquid phase at a constant temperature – 196 °