MICROSTRUCTURAL INTERACTION IN THE WAKE COHESIVE ZONE FOR SMALL CRACK-OPENING DISPLACEMENTS

Authors
Citation
Jc. Hay et Kw. White, MICROSTRUCTURAL INTERACTION IN THE WAKE COHESIVE ZONE FOR SMALL CRACK-OPENING DISPLACEMENTS, Acta materialia, 45(9), 1997, pp. 3625-3633
Citations number
40
Categorie Soggetti
Material Science","Metallurgy & Metallurigical Engineering
Journal title
ISSN journal
13596454
Volume
45
Issue
9
Year of publication
1997
Pages
3625 - 3633
Database
ISI
SICI code
1359-6454(1997)45:9<3625:MIITWC>2.0.ZU;2-1
Abstract
This study examines the role of crack-face bridging microstructural li gaments in alumina subjected to small applied displacements. Quasistat ic, monotonic loading studies have been important in the foundation of toughening mechanism characterization, where the critical features ar e of the order of the grain size. This work, however, reveals the more subtle role of subgrain-size features responsible for degradation of the R-curve by load-cycling in the small-displacement regime. Based on the current results, fatigue-related degradation depends upon damage to features of the order of 0.1 mu m, or about 0.5% of the mean grain size. Applied displacements beyond the 0.1 mu m critical displacement for this alumina resulted in nonrecoverable displacements. (C) 1997 Ac ta Metallurgica Inc.