Review: Overcoming the paradox of strength and ductility in ultrafine-grained materials at low temperatures

Kumar, Praveen and Kawasaki, Megumi and Langdon, Terence G (2016) Review: Overcoming the paradox of strength and ductility in ultrafine-grained materials at low temperatures. In: JOURNAL OF MATERIALS SCIENCE, 51 (1). pp. 7-18.

PDF jou_mat_sci_51-1_7-18_2016.pdf - Published Version Restricted to Registered users only Download (2MB) | Request a copy

Abstract

Ultrafine-grained (UFG) materials with grain sizes in the submicrometer or nanometer range may be prepared through the application of severe plastic deformation (SPD) to bulk coarse-grained solids. These materials generally exhibit high strength but only very limited ductility in low-temperature testing, thereby giving rise to the so-called paradox of strength and ductility. This paradox is examined and a new quantitative diagram is presented which permits the easy insertion of experimental data. It is shown that relatively simple procedures are available for achieving both high strength and high ductility in UFG materials including processing the material to a very high strain and/or applying a very short-term anneal immediately after the SPD processing. Significant evidence is now available demonstrating the occurrence of grain boundary sliding in these materials at low temperatures, where this is attributed to the presence of non-equilibrium grain boundaries and the occurrence of enhanced diffusion along these boundaries.

Item Type:	Journal Article
Publication:	JOURNAL OF MATERIALS SCIENCE
Publisher:	SPRINGER
Additional Information:	Copyright for this article belongs to the SPRINGER, 233 SPRING ST, NEW YORK, NY 10013 USA
Department/Centre:	Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy)
Date Deposited:	02 Dec 2015 08:32
Last Modified:	02 Dec 2015 08:32
URI:	http://eprints.iisc.ac.in/id/eprint/52858

Actions (login required)

View Item