Evaluation of Mechanical Properties of Nano-structured Al6061 Synthesized Using Machining
01 Jan 2013-Vol. 6, pp 111-118
TL;DR: In this article, the synthesis of nano-structured Al6061 using machining under plane strain and evaluation of its mechanical properties is discussed, which is in agreement with results reported in existing literature.
Abstract: This work focuses on the synthesis of nano-structured Al6061 using machining under plane strain and evaluation of its mechanical properties. It discusses an unusual application of the machining process by using it as a severe plastic deformation (SPD) process to develop nano-structured or ultra-fine grained materials. Chips obtained from this process show higher hardness than the bulk material which is in agreement with results reported in existing literature. Chips with minimum curvature have been obtained using restricted contact tool and extrusion-machining processes. Hardness of the straight chips obtained by the stated methods, though higher than the bulk material, was less than the hardness of the curled chips obtained from conventional orthogonal machining. Furthermore, hardness of the chips obtained using tool with restricted contact length of 0.6mm showed lesser variation. Hence they were used to prepare samples for the tensile test. A novel method was used to prepare small test specimens from chips to measure tensile strength. Specimens made from the chips had higher ultimate tensile strength (53%) and yield strength (85%) than that of bulk material. Improvement in strength was accompanied by a reduction in ductility (58%) for chips as compared to bulk material. It was observed that for both the chip and the bulk material, the reduction in gauge length leads to lower values of Young s modulus showing size effect.
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TL;DR: In this article, an empirical model has been developed to relate the flow stress of the drawn wire to the spacing of substructural barriers in terms of the drafting strain, which indicates that this type of strengthening mechanism is operative in the case of drawn iron wire of commercial purity.
510 citations
25 Nov 2005-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, the deformation fields associated with chip formation in plane strain machining are described and the ability to impose very large strain deformation in a controlled manner is highlighted.
Abstract: Characteristics of the deformation fields associated with chip formation in plane strain machining are described. The ability to impose very large strain deformation in a controlled manner is highlighted. The creation of nano- and ultra-fine grained structures by machining is demonstrated in a variety of metals and alloys. These results indicate that machining not only offers a simple method for large scale manufacturing of nanostructured materials, but also provides a unique experimental configuration for studying large strain deformation phenomena.
112 citations
TL;DR: In this article, the equal channel angular pressed (ECAPed) 6061 Al alloys processed with various pre- and post-ECAP heat treatments were compared in terms of the balance between strength and tensile ductility.
106 citations
25 Nov 2005-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this article, a study of characteristics of precipitation treatable aluminum alloys (6061-T6) deformed to large plastic strains, by analyzing chips created by plane strain machining, was made.
Abstract: A study has been made of characteristics of precipitation treatable aluminum alloys (6061-T6) deformed to large plastic strains, by analyzing chips created by plane strain (2-D) machining. By varying the geometry of the tool, different levels of strain were imposed in the chip in a single pass of machining. The microstructure of the chips was found to be composed of relatively equi-axed grains with mean size in the range of 70–100 nm. The evolution of the microstructure across the deformation zone has been tracked. The chip micro-hardness values were found to be somewhat greater than that reported for Al 6061-T6 deformed by equal channel angular pressing (ECAP).
85 citations