Review on Dynamic Recrystallization of Martensitic Stainless Steels during Hot Deformation: Part I—Experimental Study

Abstract

The evolution of the microstructure changes during hot deformation of high-chromium content of stainless steels (martensitic stainless steels) is reviewed. The microstructural changes taking place under high-temperature conditions and the associated mechanical behaviors are presented. During the continuous dynamic recrystallization (cDRX), the new grains nucleate and growth in materials with high stacking fault energies (SFE). On the other hand, new ultrafine grains could be produced in stainless steel material irrespective of the SFE employing high deformation and temperatures. The gradual transformation results from the dislocation of sub-boundaries created at low strains into ultrafine grains with high angle boundaries at large strains. There is limited information about flow stress and monitoring microstructure changes during the hot forming of martensitic stainless steels. For this reason, continuous dynamic recrystallization (cDRX) is still not entirely understood for these types of metals. Recent studies of the deformation behavior of martensitic stainless steels under thermomechanical conditions investigated the relationship between the microstructural changes and mechanical properties. In this review, grain formation under thermomechanical conditions and dynamic recrystallization behavior of this type of steel during the deformation phase is discussed.

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“…The precipitation behavior in high temperature is strongly related to chemical composition. [ 28,29 ]…”

An experimental and theoretical investigation of the effect of second-phase particles on grain growth during the annealing of hot-rolled AZ61 magnesium alloy

“…This restoration phenomenon tends to happens in strain hardened metals deformed at temperatures beyond half of their melting point. During hot rolling processes, the material is heated up before the process, and after during deformation, it stands simultaneous strain hardening and thermallyactivated restoration phenomena [26]. According to the deformation processing map developed for AZ61 [27], at the rolling temperature of 430 C, DRX is likely to proceed to completion, followed by grain growth.…”

Investigation on Improved Hot Processing Map of Cr4Mo4Ni4V Aerospace Bearing Steel Based on Carbide Content

“…Hot processing parameters can significantly affect the content of carbide in bearing steel, [16] and the content of carbide has an important impact on the subsequent process as well as service performance. [17][18][19][20] Therefore, the regulation of carbide content is also a crucial role in bearing steel hot processing. Tang et al [21] proposed that, with the decrease of the strain rate and the prolongation of the high-temperature holding time, the nanoscale carbides gradually dissolve in the matrix.…”