Steel superstrengthening phenomenon, part I

The phenomenon of superstrengthening of metals was for the first time discovered in Kobasko (1967) and discussed many times in scientific literature (Kobasko, 1992, 1979, 1980; Ganiev et al., 1980). It lies in the following: very intensive cooling within the martensite range results in additional strengthening (superstrengthening) of material with simultaneous improvement of its plastic properties. There is also a different point of view (Gul et al., 1989; Sverdlin et al., 2003), according to which very intensive cooling within the range higher the martensite start temperature Ms results in additional strengthening of metals due to 'freezing of vacancies', formed during heating. The author has shown that intensive cooling higher Ms does not result in superstrengthening of material and only very intensive cooling within the range of Ms/Mf yields positive results. It is of great practical and scientific interest to discuss this information widely and apply it in production.