FORMING OF NANOSTRUCTURED MATERIALS — NUMERICAL ANALYSIS IN EQUAL CHANNEL ANGULAR EXTRUSION (ECAE) OF MAGNESIUM, ALUMINIUM AND TITANIUM ALLOYS

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International Journal of Computational Engineering ScienceVol. 05, No. 02, pp. 417-424 (2004) No AccessFORMING OF NANOSTRUCTURED MATERIALS — NUMERICAL ANALYSIS IN EQUAL CHANNEL ANGULAR EXTRUSION (ECAE) OF MAGNESIUM, ALUMINIUM AND TITANIUM ALLOYSB. H. HU and J. V. KREIJB. H. HUSingapore Institute of Manufacturing Technology (SIMTech), 71 Nanyang Drive, Singapore 638075, Singapore Search for more papers by this author and J. V. KREIJC/o Singapore Institute of Manufacturing Technology (SIMTech), 71 Nanyang Drive, Singapore 638075, Singapore Search for more papers by this author https://doi.org/10.1142/S1465876304002472Cited by:1 PreviousNext AboutSectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsRecommend to Library ShareShare onFacebookTwitterLinked InRedditEmail AbstractEqual channel angular extrusion (ECAE) is a promising technique for producing ultra-fine grained (UFG) or nanostructured materials based on the principle of simple shearing. Through analysis, it is shown that only the geometrical factor Φ, namely, the half-angle of the two intersecting channels, and the number of ECAE passes, N, affect the effective strain. The equivalent linear reduction ratio, r0/r1, is derived to describe the size reduction effect of an object such as a grain. The most effective intersecting angle (2Φ) is 90°. Compared to traditional area reduction extrusion, the deformation effect is equivalent to an area reduction ratio of 1 million or a linear reduction ratio of 1022 after 12 passes of ECAE. Magnesium AZ31B, aluminium 6061 and commercially-pure Titanium were used for the study. Three types of die designs for ECAE of each alloy were proposed and numerically analysed. The effective strain, von Mises stress, equivalent area reduction ratio and equivalent linear reduction ratio were compared for the three types of die designs based on the simulation results using ANSYS/LS-DYNA. The parameter Nμ→nm, namely, the number of passes of ECAE required to reduce 100μ structures into 100nm structures, was calculated for each design. A grain size of 100μ can be deformed into a nanostructure through as few as 12-17 passes of ECAE.Keywords:Equal channel angular extrusion (ECAE)numerical simulationnanostructuresimple shearmaterials processingplastic deformation References M. C. Roco, J. of Nanoparticle Research 3(5-6), 353 (2001). Crossref, Google Scholar Kimet al., Scripta Materialia 45, 575 (2001). Crossref, Google ScholarL. R. Corwellet al., Materials Characterisation 37, 295 (1996). Google Scholar H. G. Selam, Proceedings of ICCE/9 (San Diego, July 1-6, 2002), p. 689 . Google ScholarV. M. Segal, Materials. Science. & Engineering. A197, 157 (1995). Google Scholar S. C. Chen, Z. Q. Wu, B. H. Hu, J. Liang & B. J. Wu, Hot-working Technology (Tsinghua University, 1992), p. 150 . Google Scholar FiguresReferencesRelatedDetailsCited By 1Finite element modelling and simulation of bulk material formingJaroslav Mackerle1 Apr 2006 | Engineering Computations, Vol. 23, No. 3 Recommended Vol. 05, No. 02 Metrics History KeywordsEqual channel angular extrusion (ECAE)numerical simulationnanostructuresimple shearmaterials processingplastic deformationPDF download