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Indexed by:期刊论文

Date of Publication:2012-09-30

Journal:MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

Included Journals:SCIE、EI、Scopus

Volume:554

Page Number:6-11

ISSN No.:0921-5093

Key Words:Al2O3-ZrO2 (3Y) ceramic; Superplastic compression; TiO2 dopants; Microstructure development; Deformation mechanism

Abstract:Compression deformation deformation behavior and mechanism of as-sintered Al2O3-ZrO2 (3Y) composite ceramics doped with four different amounts of TiO2 (0, 1, 4, and 8 wt.%, designated as 0T, 1T, 4T, and 8T) were systematically investigated in this work. It was found out that the strain rate significantly increased by doping TiO2 addition. The stress-jump deformation data showed that the strain rate of 8T was about two orders of magnitude higher than that of the undoped ceramic under the same flow stress. Then, the microstructures were examined. After deformation, texture was developed but its intensity decreases with increasing TiO2 concentration. Moreover, liquid phases (about 50-100 nm) were observed along the edge facets and at the junction pockets in deformed 4T and 8T specimens. Based on the microstructural features and deformation behavior, it is suggested that for 0T and 1T, the deformation mechanism was texture-controlled grain boundary sliding accompanied by diffusion; for 4T and 8T, it was grain boundary sliding accompanied by the liquid phases. (c) 2012 Elsevier B.V. All rights reserved.