Bulk nanostructured (ns)/ultrafine-grained (UFG) metallic materials possess very high strength, making them attractive for high strength, lightweight and energy efficient applications. The most effective approach to produce bulk ns/UFG metallic materials is severe plastic deformation (SPD). In the last 30 years, significant research efforts have been made to explore SPD processing of materials, SPD-induced microstructural evolutions, and the resulting mechanical properties. There have been a few comprehensive reviews focusing mainly on SPD processing and the mechanical properties of the resulting materials. Yet no such a review on SPD-induced microstructural evolutions is available. This paper aims to provide a comprehensive review on important microstructural evolutions and major microstructural features induced by SPD processing in single-phase metallic materials with face-centered cubic structures, body-centered cubic structures, and hexagonal close-packed structures, as well as in multi-phase alloys. The corresponding deformation mechanisms and structural evolutions during SPD processing are discussed, including dislocation slip, deformation twinning, phase transformation, grain refinement, grain growth, and the evolution of dislocation density. A brief review on the mechanical properties of SPD-processed materials is also provided to correlate the structure with mechanical properties of SPD-processed materials, which is important for guiding structural design for optimum mechanical properties of materials.

Structural evolutions of metallic materials processed by severe plastic deformation

Development of low-alloyed and rare-earth-free magnesium alloys having ultra-high strength

Recent developments in rare-earth free wrought magnesium alloys having high strength: A review

Mechanistic investigation of a low-alloy Mg–Ca-based extrusion alloy with high strength–ductility synergy

Ultrafine-grain metals by severe plastic deformation

Room-temperature equal channel angular extrusion of pure magnesium

Asymmetric rolling (AsR) was carried out to achieve a gradient ultrafine ferrite and martensite duplex structure in a commercial low-carbon microalloyed steel and compared with symmetric rolling. Two specific fiber textures 〈110〉//RD and 〈111〉//ND were developed through the thickness when imposing shear strains by AsR. In hibition of plastic instability in the ultrafine ferrite was closely associated with the gradient grain-size distribution, beneficial shear fiber textures and the dispersed martensite, resulting in high strength (~905 MPa) with good ductility (~17%).

Gradient ultrafine ferrite and martensite structure and its tensile properties by asymmetric rolling in low carbon microalloyed steel

In this study, severe plastic deformation (SPD) of Ti-bearing interstitial-free steel was carried out by multi-axial forging (MAF) technique. The grain refinement achieved was comparable to that by other SPD techniques. A considerable heterogeneity was observed in the microstructure and texture. Texture of multi-axially forged steels has been evaluated and reported for the first time. The material exhibited a six-fold increase in the yield strength after four cycles of MAF.

Microstructure and Texture Evolution in Interstitial-Free (IF) Steel Processed by Multi-Axial Forging

The texture evolution is wearing the signature of the deformation path in plastic deformation. In asymmetric rolling, plain strain compression and shear are the main components of the imposed strain. In this work, viscoplastic self-consistent (VPSC) simulations of the texture evolution were used to determine the combination and sequence of the two deformation components. It has been found that the deformation path is composed of two parts in asymmetric rolling: it is first essentially rolling, followed by the simple shear process. Simultaneous rolling and shear process cannot produce the observed textures, while the decomposed simulation can reproduce it faithfully.

https://www.mdpi.com/1996-1944/13/1/101/pdf

Satyaveer Singh Dhinwal

Papers

Room-temperature equal channel angular extrusion of pure magnesium

Gradient ultrafine ferrite and martensite structure and its tensile properties by asymmetric rolling in low carbon microalloyed steel

Microstructure and Texture Evolution in Interstitial-Free (IF) Steel Processed by Multi-Axial Forging

Unlocking Deformation Path in Asymmetric Rolling by Texture Simulation

Effect of strain path change on texture and microstructure evolution in asymmetric rolled extra-low carbon steel