TY - JOUR
T1 - Microstructure and mechanical properties of a directionally solidified Al2O3/Y3Al5O12/ZrO2 hypoeutectic in situ composite
AU - Su, Haijun
AU - Zhang, Jun
AU - Liu, Lin
AU - Fu, Hengzhi
PY - 2009/12
Y1 - 2009/12
N2 - Directionally solidified ternary Al2O3/Y3Al5O12(YAG)/ZrO2 hypoeutectic rod composites were successfully fabricated by the laser zone remelting technique. The microstructure and mechanical properties of the composite were investigated. The microstructure presented a complex three-dimensional network structure consisting of fine Al2O3 (41 vol.%) and YAG (49 vol.%) phases, with smaller ZrO2 (10 vol.%) phases partially distributed at the Al2O3/YAG interfaces. The irregular growth behavior in the hypoeutectic was revealed. The hardness and fracture toughness at ambient temperature were measured to be 17.3 GPa and 5.2 MPa m1/2, respectively. The toughness enhancement in comparison with previous binary Al2O3/YAG composites was mainly attributed to the refined microstructure, and crack deflection, branching and bridging. Moreover, the residual stresses, generated by different thermal expansion coefficients of the component phases, also importantly contributed to the improved toughness. Correlations between the addition of the third component ZrO2 and the microstructure and properties were discussed as well.
AB - Directionally solidified ternary Al2O3/Y3Al5O12(YAG)/ZrO2 hypoeutectic rod composites were successfully fabricated by the laser zone remelting technique. The microstructure and mechanical properties of the composite were investigated. The microstructure presented a complex three-dimensional network structure consisting of fine Al2O3 (41 vol.%) and YAG (49 vol.%) phases, with smaller ZrO2 (10 vol.%) phases partially distributed at the Al2O3/YAG interfaces. The irregular growth behavior in the hypoeutectic was revealed. The hardness and fracture toughness at ambient temperature were measured to be 17.3 GPa and 5.2 MPa m1/2, respectively. The toughness enhancement in comparison with previous binary Al2O3/YAG composites was mainly attributed to the refined microstructure, and crack deflection, branching and bridging. Moreover, the residual stresses, generated by different thermal expansion coefficients of the component phases, also importantly contributed to the improved toughness. Correlations between the addition of the third component ZrO2 and the microstructure and properties were discussed as well.
KW - A. Ceramic-matrix composites (CMCs)
KW - B. Fracture toughness
KW - C. Crack
KW - D. Microstructure and properties
KW - E. Directional solidification
UR - http://www.scopus.com/inward/record.url?scp=70350077108&partnerID=8YFLogxK
U2 - 10.1016/j.compscitech.2009.08.007
DO - 10.1016/j.compscitech.2009.08.007
M3 - 文章
AN - SCOPUS:70350077108
SN - 0266-3538
VL - 69
SP - 2657
EP - 2667
JO - Composites Science and Technology
JF - Composites Science and Technology
IS - 15-16
ER -