High-pressure torsion of hafniurn

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

卷:527

Article

Edalati, Kaveh¹  Horita, Zenji¹  Mine, Yoji^2,3 

[1] Kyushu Univ, Fac Engn, Dept Mat Sci & Engn, Fukuoka 8190395, Japan

[2] Kyushu Univ, Fac Engn, Dept Mech Engn, Fukuoka 8190395, Japan

[3] Natl Inst Adv Ind Sci & Technol, Res Ctr Hydrogen Ind Use & Storage HYDROGENIUS, Fukuoka 8190395, Japan

关键词: Hafnium;    Hydrides;    Hydrogen;    High-pressure torsion;    Severe plastic deformation;    Ultrafine-grained structure;   

DOI  :  10.1016/j.msea.2009.11.060

来源: Elsevier

【 摘 要 】

Pure Hf (99.99%) is processed by high-pressure torsion (HPT) under pressures of 4 and 30 GPa to form an ultrafine-grained structure with a gain size of similar to 180 nm. X-ray diffraction analysis shows that, unlike Ti and Zr, no omega phase formation is detected after HPT processing even under a pressure of 30 GPa. A hydride formation is detected after straining at the pressure of 4 GPa. The hydride phase decomposes either by application of a higher pressure as 30 GPa or by unloading for prolong time after HPT processing. Microhardness, tensile and bending tests show that a high hardness (360 Hv) and an appreciable ductility (8%) as well as high tensile and bending strength (1.15 and 2.75 GPa, respectively) are achieved following the high-pressure torsion. (C) 2009 Elsevier B.V. All rights reserved.

【 授权许可】

Free