Critical parameters of heat-treating process are time, temperature and cooling rate.
Some phase transformations of the steel (e.g. tempering) are controlled by diffusion processes, which are strongly dependent on time and are relatively slow.
On the other hand, Martensite formation (by quenching austenite to room temperature), depends only on temperature and not on time. Fraction of a second is sufficient for this type of transformation.
I expect similar processes also during grinding. In this case we expose the edge to short heat pulses, which are probably not long enough to enable diffusion processes, but may locally rise the temperature sufficiently to initiate some shear-type transformation of Martensite, which solely depends on temperature.
Jan
Some phase transformations of the steel (e.g. tempering) are controlled by diffusion processes, which are strongly dependent on time and are relatively slow.
On the other hand, Martensite formation (by quenching austenite to room temperature), depends only on temperature and not on time. Fraction of a second is sufficient for this type of transformation.
I expect similar processes also during grinding. In this case we expose the edge to short heat pulses, which are probably not long enough to enable diffusion processes, but may locally rise the temperature sufficiently to initiate some shear-type transformation of Martensite, which solely depends on temperature.
Jan