Grain refinement of pure vanadium by equal channel angular pressing

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 479; no. 1; pp. 285 - 292
• Main Authors: Jiang, Z.Z., Yu, S.H., Chun, Y.B., Shin, D.H., Hwang, S.K.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 25.04.2008; Elsevier
• Subjects: Cold working, work hardening; annealing, quenching, tempering, recovery, and recrystallization; textures; Cross-disciplinary physics: materials science; rheology; ECA pressing; Exact sciences and technology; Grain refinement; Materials science; Mechanical properties; Other heat and thermomechanical treatments; Physics; Recrystallization; Texture; Treatment of materials and its effects on microstructure and properties; Vanadium; Mechanical properties; ECA pressing; Texture; Grain refinement; Vanadium; Recrystallization; Grain size; High strain; Equiaxed structure; Plastic deformation; ECAP; Heat treatments; Tensile strength; Transition elements; Yield strength; Microstructure
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2007.06.052

Commercial vanadium of 99.8% purity was extensively grain-refined by application of equal channel angular pressing at 350 °C. A total of eight passes via route B C reduced the grain size from 100 μm to 200 nm. In the as-deformed state, the microstructure consisted mainly of lamellar grains and a smaller fraction of equiaxed grains. A strong fiber texture consisting of <1 1 1> θ and {1 1 0} θ components was also produced by severe plastic deformation. More than a threefold increase of the yield strength was realized by the processing, and a balanced combination of strength and tensile elongation, 406 MPa and 32%, respectively, was obtainable by subsequent recrystallization heat treatment at 700 °C. Dynamic recovery and continuous recrystallization are thought to be the key mechanisms with regard to characterizing the microstructure evolution during deformation and recrystallization, respectively.