ISSN:
1662-9752
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The strength of a deformed metal depends on the content of high angle boundaries, lowangle dislocation boundaries and the dislocations between the boundaries. High angle boundariescontribute by Hall-Petch strengthening, whereas for the low angle dislocation boundaries anddislocations between boundaries the strengthening is proportional to the square root of the dislocationdensity. Based on an assumption of additivity of these contributions, the flow stresses of metalsdeformed by cold rolling have been calculated successfully. In the present investigation pure Ni(99.9%) has been deformed by high pressure torsion (HPT) to von Mises strains of 0.9, 1.7, 8.7 and 12.The strength of the HPT Ni has been determined by Vickers microhardness (HV) measurements andthe microstructural parameters have been determined by transmission electron microscope (TEM) inthe longitudinal section. HPT has been compared with deformation by cold rolling and torsion basedon the structural evolution with strain and the stress-structure relationship. Based on an assumption ofa linear additivity of boundary strengthening and dislocation strengthening, good agreement has beenfound between the calculated and the experimental flow stress
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/02/19/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.584-586.417.pdf
