Efeitos de transformações de fase na recristalização em aços baixo carbono

Abstract

Phenomena such as recrystallization and phase transformation involve nucleation and grain growth steps, respectively. Both depend on diffusion, in other words, time, temperature and chemical potential. When both, recrystallization and diffusion, occur on metal at the same time, different mechanical properties rather than those observed when each phenomena occurs singly. Therefore, the purpose of this research is to study the recrystallization in conjunction with the phase transformation on low carbon steels, analyzing the results of this interaction. For this research, previously strain hardened low carbon steel samples were submitted to four different recrystallization temperatures (first one to below the eutectoid temperature, two other to next to the two-phase field and the last one in the austenitic zone); and after the process was complete, the samples were submitted to hardness and micrographs evaluation. The results showed that when recrystallization occurs in conjunction with phase transformation, the drop in hardness is lower than when recrystallization occurs alone, below the eutectoid zone. These results are interesting to industrial process where the decrease in strength obtained by hardening is not wanted.