Influence of grain shape and orientation on the mechanical properties of high pressure torsion deformed nickel

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:560

Article

Rathmayr, Georg B.¹  Hohenwarter, Anton²  Pippan, Reinhard¹ 

[1] Austrian Acad Sci, Erich Schmid Inst Mat Sci, A-8700 Leoben, Austria

[2] Univ Leoben, Dept Mat Phys, A-8700 Leoben, Austria

关键词: High pressure torsion (HPT);    Severe plastic deformation (SPD);    Nickel;    Orientation dependency;    Plastic anisotropy;   

DOI  :  10.1016/j.msea.2012.09.061

来源: Elsevier

【 摘 要 】

Severely plastically deformed (SPD) materials, for example those produced by high pressure torsion (HPT), are reported to possess outstanding mechanical properties. A typical HPT microstructure consists of elongated grains, usually of grain size well below 1 gm, which are aligned parallel to the shear plane and showing typical shear texture components. To answer the question of how these single features of a SPD microstructure affect the mechanical properties individually, such as the yield strength, the ultimate tensile strength, the uniform elongation and the reduction in area, uniaxial tensile tests have been conducted. The samples were tested in two different orientations. Within the same testing orientation the average grain aspect ratio was also varied. The variation in grain aspect ratio within a sample was achieved through a slight back rotation of the already deformed material and selective radius-dependent specimen extraction. The main results are as follows: the ductility (in terms of the reduction in area) is influenced by the grain aspect ratio. In contrast, the ultimate tensile strength is independent of the grain aspect ratio but shows an explicit dependency on the specimen orientation. (C) 2012 Elsevier B.V. All rights reserved.

【 授权许可】

Free