Influence of Microstructure on Fatigue Fracture Characteristics of Al2O3

URI http://harp.lib.hiroshima-u.ac.jp/it-hiroshima/metadata/7128
File
Title
Influence of Microstructure on Fatigue Fracture Characteristics of Al2O3
Author
氏名 Kido Mitsuo
ヨミ キド ミツオ
別名 木戸 光夫
氏名 Katayama Gounozyo
ヨミ カタヤマ ゴウノジョウ
別名
氏名 Inoda Nana
ヨミ イノダ ナナ
別名
氏名 Tsuchibushi Yasuyuki
ヨミ ツチブシ ヤスユキ
別名
Subject
Al2O3 ceramics
Grain morphology
Grain boundary phase
Grain bridging effect
Stress corrosion cracking
NDC
531.2
Abstract

Fatigue fracture characteristics under static and cyclic loading were investigated for three kinds of Al2O3, with microstructures controlled by sintering additives (MgO, SiO2+CaO) and particle size. The microstructures were: fine equi-axed grains (Material M, MgO added), coarse columnar grains (Material SC, SiO2+CaO added) and fine columnar grains (Material SC-f, SiO2+CaO added). The crack propagation rates da/dN of Material SC was accelerated in water. The measurements of R-curve behavior and COD under cyclic loading showed that the grain bridging effect of Material SC was reduced further than that of Material SC-f. In addition, surface analysis by EDX on fatigue fracture surfaces in Material SC showed that Si and Ca, the components of the sintering additives, were decreased markedly at SCG sites under cyclic loading in water. Consequently, it is concluded that the degradation of fatigue strength in Material SC under cyclic loading in water was caused by the activation of a hydration reaction at grain boundaries in the crack tip and a marked decrease in the grain bridging effect (i.e., an increase in Ktip).

Journal Title
広島工業大学研究紀要
Volume
33
Spage
67
Epage
74
Published Date
36192
Publisher
広島工業大学
ISSN
3851672
NCID
AN0021271X
Language
eng
NIIType
Departmental Bulletin Paper
Text Version
出版社版
Relation URL
Old URI
Set
it-hiroshima