EFFECTS OF THE LIQUID-PHASE ON THE HIGH-TEMPERATURE TENSILE DUCTILITY- FROM EMBRITTLEMENT TO SUPERPLASTICITY

Citation
J. Koike et al., EFFECTS OF THE LIQUID-PHASE ON THE HIGH-TEMPERATURE TENSILE DUCTILITY- FROM EMBRITTLEMENT TO SUPERPLASTICITY, Philosophical magazine. A. Physics of condensed matter. Structure, defects and mechanical properties, 78(3), 1998, pp. 599-614
Citations number
49
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics, Applied","Material Science","Physics, Condensed Matter","Metallurgy & Metallurigical Engineering
ISSN journal
1364-2804
Volume
78
Issue
3
Year of publication
1998
Pages
599 - 614
Database
ISI
SICI code
1364-2804(1998)78:3<599:EOTLOT>2.0.ZU;2-6
Abstract
Inclusions of liquid phase are generally considered to cause liquid-me tal embrittlement. On the other hand, there have been some reports imp lying the enhancement of tensile elongation by liquid inclusions. In t his paper, the possibility of elongation enhancement by liquid and its underlying mechanism were investigated in a model binary system of Al -Bi and a composite of(Al-Mg)-Si3N4. Clear evidence of elongation enha ncement was observed in the Al-Bi alloy. Liquid inclusions of Bi were found to assist stress accommodation processes and to delay cavitation failure. In the (Al-Mg)-Si3N4 composite, a close correlation was foun d between the incipient melting temperature and an optimum temperature for high-strain-rate superplasticity. The liquid phase was observed a long grain boundaries and interfaces of the composite, suggesting a si milar stress accommodation process to that of the Al-Bi alloy. The int erface microstructure was also studied by high-resolution transmission electron microscopy to understand the detailed mechanism of high-stra in-rate superplasticity.