Microstructural refinement of Al before compression with oscillatory torsion process

• Autorzy: Rodak K.
• Języki publikacji: EN

Abstrakty

EN

Purpose: The present study is aimed at a quantitative description of microstructural parameters as a average subgrain size, subgrain width and length of Al deformed by using compression test at ε=0.8 with the next annealing. Conventional compression followed by annealing as a preliminary stage for compression with oscillatory torsion should contribute to refining grain size. Design/methodology/approach: Al samples were compressed in room temperature to a true strain of 0.8 and next annealed at 250 °C for 1 min and 1h. Structural investigations were conducted by using light microscopy (LM) and transmission electron microscopy (TEM). Findings: Compression leads to the formation of elongated subgrains bounded by microbands. The average subgrain size increase steadily with annealing time. The aspect ratio (R) of the grain length and the grain width is high initially especially for the as compressed materials and decreasing significantly after annealing. On annealing the deformed material, dislocation recovery occurs, leading to reductions in dislocation density both at grain boundaries and within the grains. Some of the dislocations arrange to form small eqiuaxed subboundaries. Research limitations/implications: An increase of the contribution of grain boundary (by using method of preliminary refining structure of Al) to the deformation process by compression with oscillatory torsion may influence on more refining Al structure than compression with oscillatory torsion only. Originality/value: Contributes to research on deformation procedure to achieve a refine structure of metals.

Słowa kluczowe

EN

nanomaterials; Al; microstructure; severe plastic deformation

PL

nanomateriały; aluminium; mikrostruktura; odkształcanie plastyczne

• Wydawca: International OCSCO World Press
• Czasopismo: Archives of Materials Science and Engineering
• Rocznik: 2007
• Tom: Vol. 28, nr 6
• Strony: 357--360
• Opis fizyczny: Bibliogr. 15 poz., il., wykr.

Twórcy

autor

Rodak K.

• Department of Materials Science, Silesian University of Technology, ul. Krasińskiego 8, 40-019 Katowice, Poland,

Bibliografia

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