TY - GEN
T1 - Laser zone-remelted alumina-based eutectic in situ composite
AU - Jun, Zhang
AU - Haijun, Su
AU - Lin, Liu
AU - Hengzhi, Fu
PY - 2007
Y1 - 2007
N2 - Due to excellent oxidation and corrosion resistance at elevated temperature, oxide ceramic could be the preference served at high temperature oxidizing atmosphere over a long period of time. In recent years, alumina-based eutectic in situ composite prepared by various solidification techniques, which has superior properties even close to the melting point about 2100K, has been paid much attention. In this paper, Al2O3/YAG/ZrO 2 ternary eutectic and hypoeutectic ceramics are prepared from melt by laser zone-remelting technique, the rapid solidification characteristic and the mechanical property of the composites are investigated. The results show that: (1) Compared to sintered composite with the same composition, laser zone-remelted Al2O3/YAG/ZrO2 eutectic in situ composite has different microstructure showing fine interpenetrated network with Al2O3, YAG and ZrO2 phases continuously intergrown, while none of pores, grain boundaries and amorphous phases is found. (2) The scanning rate and the power density of the laser beam has strong effect on the microstructure morphology. When the power density is determined, the eutectic spacing is reduced with the scanning rate increased. The characteristic eutectic spacings and phase sizes of YAG and Al2O3 are about 2-3μm, and the characteristic dimension of ZrO2 is less than 1μm. (3) The hardness and the room-temperature fracture toughness of Al 2O3/YAG/ZrO2 eutectic are respectively H V=16.7±2.0 GPa and KIC=8.0±2.0 MPam 1/2, and those of hypoeutectic are respectively Hv=15. 8±2.0 GPa and KIC=3.9±1.0MPam1/2.
AB - Due to excellent oxidation and corrosion resistance at elevated temperature, oxide ceramic could be the preference served at high temperature oxidizing atmosphere over a long period of time. In recent years, alumina-based eutectic in situ composite prepared by various solidification techniques, which has superior properties even close to the melting point about 2100K, has been paid much attention. In this paper, Al2O3/YAG/ZrO 2 ternary eutectic and hypoeutectic ceramics are prepared from melt by laser zone-remelting technique, the rapid solidification characteristic and the mechanical property of the composites are investigated. The results show that: (1) Compared to sintered composite with the same composition, laser zone-remelted Al2O3/YAG/ZrO2 eutectic in situ composite has different microstructure showing fine interpenetrated network with Al2O3, YAG and ZrO2 phases continuously intergrown, while none of pores, grain boundaries and amorphous phases is found. (2) The scanning rate and the power density of the laser beam has strong effect on the microstructure morphology. When the power density is determined, the eutectic spacing is reduced with the scanning rate increased. The characteristic eutectic spacings and phase sizes of YAG and Al2O3 are about 2-3μm, and the characteristic dimension of ZrO2 is less than 1μm. (3) The hardness and the room-temperature fracture toughness of Al 2O3/YAG/ZrO2 eutectic are respectively H V=16.7±2.0 GPa and KIC=8.0±2.0 MPam 1/2, and those of hypoeutectic are respectively Hv=15. 8±2.0 GPa and KIC=3.9±1.0MPam1/2.
KW - AlO/YAG/ZrO
KW - Eutectic In situ composite
KW - Laser zone-remelting
UR - http://www.scopus.com/inward/record.url?scp=38349058265&partnerID=8YFLogxK
U2 - 10.4028/www.scientific.net/msf.539-543.832
DO - 10.4028/www.scientific.net/msf.539-543.832
M3 - 会议稿件
AN - SCOPUS:38349058265
SN - 0878494286
SN - 9780878494286
T3 - Materials Science Forum
SP - 832
EP - 836
BT - Supplement to THERMEC 2006, 5th International Conference on PROCESSING and MANUFACTURING OF ADVANCED MATERIALS, THERMEC 2006
PB - Trans Tech Publications Ltd
T2 - 5th International Conference on Processing and Manufacturing of Advanced Materials - THERMEC'2006
Y2 - 4 July 2006 through 8 July 2006
ER -