is known most common materials as steel, that the conversion rate without diffusion martensitic have a degree of progress that depends only on the temperature. That is, exceeded a certain speed of cooling required to grow non-nuclear and equilibrium phases, the high temperature phase (austenite steel) without diffusion transforms into a new phase (martensite BCT). The percentage of transformed material is related to the temperature at which cooling ends. Within the group of alloys with phase changes occur without diffusion, the temperature at which transformation begins as the alloy cools, it is called Ms (martensite start) and the temperature at which no longer show phase changes as long as the cooling process continues, it is called Mf (martensite finish). If cooling is interrupted, that is, if the temperature remains constant during a finite time, transformation does not evolve, but maintains the percentages of phases corresponding to that temperature. Conversely (and not in the case of steel, but in general), when heating the alloy, and a temperature exceeding As (austenite start) the alloy begins to transform to the primary phase, or high temperature and finished to transform when the temperature exceeds Af (austenite finish) or what is, when the temperature is greater than Af all the alloy is in primordial phase high temperature.
Maria Linares 19881179 EES
Sec 1
0 comments:
Post a Comment