Nanostructured Low Carbon Steels Obtained from the Martensitic State via Severe Plastic Deformation, Precipitation, Recovery, and Recrystallization

Abstract

The range of accessible microstructures from the combination of severe plastic deformation (SPD) and heat treatments of a low carbon steel martensite under various processing conditions is evaluated. SPD results in a temperature decrease for recrystallization and austenitization upon subsequent annealing. On the contrary, the precipitation of cementite takes place at higher temperatures after SPD. Whereas, a certain thermal stability is observed for subsequent processing, even low annealing temperatures have a strong impact on the results of simultaneous SPD and heat treatments which results from the differences of dynamic and static recovery. It is shown that with each processing sequence unique microstructures can be produced that have to be taken into account in order to produce a material with optimized tailored properties.

Comparison of the Thermal Stability in Equal‐Channel‐Angular‐Pressed and High‐Pressure‐Torsion‐Processed Fe–21Cr–5Al Alloy

“…[15] The degree of grain refinement is not only dependent on the corresponding SPD technique but also on the processing temperature. [16][17][18][19] Generally, the deformation temperature is preferred to be less than 0.3T m , where T m is the melting temperature in K, to predominantly achieve 70 to 80% of high-angle GBs (HAGB, GB misorientation >15°). [12,20] However, some metals and alloys cannot be processed at those temperatures owing to their limited workability.…”

Effect of Excessive Fe2O3 on Microstructural Evolution of Micro/Nanocrystalline 2205 Duplex Stainless Steel Prepared by Aluminothermic Reaction

“…At present, the methods to obtain refined grains mainly include the addition of rare earth elements (Liu et al, 2010) or large plastic deformation (Korznikov et al, 1994;Yanushkevich et al, 2016;Müller et al, 2019). However, economically, these two methods are not appropriate for mass production.…”

An Overview on the Corrosion Behavior of Steels Processed by Severe Plastic Deformation

“…High-Pressure torsion has also been used to process low and medium-carbon steel, low alloyed, and mild steel (7,8,38,39,40) . The studies have shown the occurrence of elongated grains and the dissolution of carbide precipitates and other phase colonies such as pearlite and cementite.…”