Hardenability Of Steel
While a piece of metal is quenched its loss of heat is calculated by various factors but ore face can be simply understood such the loss will not be standardized from total volume. That part of the metal such is in direct contact along with quenching media will lose heat faster than the inner side. It will bring diameter or thickness of the part into focus to play a significant role in hardening. Following figure represents the cooling curves for surface, for material merely underneath the surface and the core. The cooling rate within the material is governed via thermal conductivity of the steel. This is the function also of the thermal gradient existing inside the piece to be hardened. There is all times a possibility such that at the inner core the rate of cooling is less than the critical rate consequential into unhardened material present there.