title: Ultrafine-grained porous titanium and porous titanium/magnesium composites fabricated by space holder-enabled severe plastic deformation.
abstract: Compaction of powders by equal channel angular pressing (ECAP) using a novel space holder method was employed to fabricate metallic scaffolds with tuneable porosity. Porous Ti and Ti/Mg composites with 60% and 50% percolating porosity were fabricated using powder blends with two kinds of sacrificial space holders. The high compressive strength and good ductility of porous Ti and porous Ti/Mg obtained in this way are believed to be associated with the ultrafine grain structure of the pore walls. To understand this, a detailed electron microscopy investigation was employed to analyse the interface between Ti/Ti and Ti/Mg particles, the grain structures in Ti particles and the topography of pore surfaces. It was found that using the proposed compaction method, high quality bonding between particles was obtained. Comparing with other powder metallurgy methods to fabricate Ti with an open porous structure, where thermal energy supplied by a laser beam or high temperature sintering is essential, the ECAP process conducted at a relatively low temperature of 400°C was shown to produce unique properties.
authors.affiliation: Centre for Advanced Hybrid Materials, Department of Materials Engineering, Monash University, Clayton, Victoria 3800, Australia. Electronic address: yuanshen.qi@monash.edu.
authors.forename: Yuanshen
authors.initials: Y
authors.lastname: Qi
authors.affiliation: Monash Institute of Medical Engineering, Faculty of Engineering, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: Karla G
authors.initials: KG
authors.lastname: Contreras
authors.affiliation: Liquid Processing & Casting Technology R&D Group, Korea Institute of Industrial Technology, Incheon 406-840, Republic of Korea; Department of Materials Science and Engineering, Seoul National University, Seoul 151-742, Republic of Korea.
authors.forename: Hyun-Do
authors.initials: HD
authors.lastname: Jung
authors.affiliation: Department of Materials Science and Engineering, Seoul National University, Seoul 151-742, Republic of Korea; Advanced Institutes of Convergence Technology, Seoul National University, Gwanggyo, Yeongtong-gu, Suwon-si, Gyeonggi-do 443-270, Republic of Korea.
authors.forename: Hyoun-Ee
authors.initials: HE
authors.lastname: Kim
authors.affiliation: Centre for Advanced Hybrid Materials, Department of Materials Engineering, Monash University, Clayton, Victoria 3800, Australia.
authors.forename: Rimma
authors.initials: R
authors.lastname: Lapovok
authors.affiliation: Centre for Advanced Hybrid Materials, Department of Materials Engineering, Monash University, Clayton, Victoria 3800, Australia; Laboratory of Hybrid Nanostructured Materials, NUST MISiS, Moscow 119490, Russia. Electronic address: yuri.estrin@monash.edu.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Estrin
mesh_terms: D006358:Hot Temperature; D008274:Magnesium / Q000737:chemistry*; D011312:Pressure; D014025:Titanium / Q000737:chemistry*
chemical_list: D014025:Titanium; D008274:Magnesium
keywords: Equal channel angular pressing compaction; Microstructure; Porous Ti; Porous Ti/Mg composite; Space holder method