EVIDENCE OF GRAIN-BOUNDARY-SLIDING-INDUCED CAVITATION IN CERAMICS UNDER COMPRESSION

被引:23
作者
BLANCHARD, CR
CHAN, KS
机构
[1] Southwest Research Institute, San Antonio, Texas
关键词
D O I
10.1111/j.1151-2916.1993.tb06631.x
中图分类号
TQ174 [陶瓷工业]; TB3 [工程材料学];
学科分类号
0805 ; 080502 ;
摘要
Detailed microscopy of two crept aluminas, one with (AD99) and one without (Lucalox) a grain boundary glassy phase, has been performed to determine the pertinent damage mechanisms during creep. Evidence is presented for a nucleation-controlled cavitation process where creep cavities nucleate primarily on two-grain facets, followed by cavity growth and coalescence to form grain-facet-sized cavities and microcracks. A variety of creep cavity morphologies were observed in Lucalox, including spheroidal and irregularly shaped cavities. The latter finding implies a strong influence of crystallographic orientation and the corresponding surface energy of the cavitated planes on the cavity shape. In contrast, classical spheroidal cavities were observed in AD99 due to the presence of a viscous phase along grain boundaries. Direct evidence for grain boundary sliding as the process driving force for cavitation in Lucalox is presented together with evidence for the nucleation of creep cavities at grain boundary ledges. These findings are compared to the grain boundary sliding (GBS) and small-angle neutron scattering (SANS) measurements performed previously on the same systems. Based on this study, the cavity nucleation process in the glassy-phase- and non-glassy-phase-containing aluminas is apparently similar as both involve the nucleation of rows of equally sized and equally spaced cavities.
引用
收藏
页码:1651 / 1660
页数:10
相关论文
共 31 条
[1]  
Argon A.S., 1980, CREEP FATIGUE ENV IN, P46
[2]   GRAIN-BOUNDARY SLIDING MEASUREMENTS IN AL2O3 BY MACHINE VISION PHOTOGRAMMETRY [J].
BLANCHARD, CR ;
PAGE, RA .
JOURNAL OF MATERIALS SCIENCE, 1991, 26 (12) :3165-3170
[3]   GRAIN-BOUNDARY SLIDING MICRODISPLACEMENT MEASUREMENTS DURING THE CREEP OF ALUMINA [J].
BLANCHARD, CR ;
PAGE, RA .
JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 1992, 75 (06) :1612-1620
[4]  
BLANCHARD CR, UNPUB
[5]   CREEP-BEHAVIOR AND GRAIN-BOUNDARY SLIDING IN POLYCRYSTALLINE [J].
CANNON, WR ;
SHERBY, OD .
JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 1977, 60 (1-2) :44-47
[6]   ELECTRON-DIFFRACTION AND MICROSCOPY STUDIES OF THE STRUCTURE OF GRAIN-BOUNDARIES IN AL2O3 [J].
CARTER, CB ;
KOHLSTEDT, DL ;
SASS, SL .
JOURNAL OF THE AMERICAN CERAMIC SOCIETY, 1980, 63 (11-1) :623-627
[7]   TRANSIENT CAVITY GROWTH IN CERAMICS UNDER COMPRESSION [J].
CHAN, KS ;
PAGE, RA .
JOURNAL OF MATERIALS SCIENCE, 1992, 27 (06) :1651-1658
[8]   CONTINUOUS CREEP CAVITY NUCLEATION BY STOCHASTIC GRAIN-BOUNDARY SLIDING [J].
CHAN, KS ;
PAGE, RA .
JOURNAL OF MATERIALS SCIENCE, 1990, 25 (11) :4622-4629
[9]   CAVITY NUCLEATION AT GRAIN-BOUNDARY LEDGES [J].
CHAN, KS ;
PAGE, RA ;
LANKFORD, J .
ACTA METALLURGICA, 1986, 34 (12) :2361-2370
[10]  
CHANG TJ, 1982, J AM CERAM SOC, V65, P93