TY - JOUR
T1 - Rapid solidification behaviour of Al2O3/Y3Al5O12 (YAG) binary eutectic ceramic in situ composites
AU - Su, Haijun
AU - Zhang, Jun
AU - Cui, Chunjuan
AU - Liu, Lin
AU - Fu, Hengzhi
PY - 2008/4/25
Y1 - 2008/4/25
N2 - Rapid solidification of Al2O3/Y3Al5O12 (YAG) binary eutectic ceramic in situ composites during the remelting process using high-energy laser, which results in refinement of the solidification microstructure and improvement of the mechanical properties, is studied in this paper. The rapidly solidified Al2O3/YAG eutectic consists of Al2O3 and YAG phases without any other phases, effectively avoiding grain boundaries. The eutectic interspacing is extremely refined due to the high-temperature gradient and solidification rate of laser rapid solidification, and the minimal interspacing is as fine as 0.5 μm. The eutectic exhibits an obvious faceted-faceted eutectic growth characteristic which mainly derives from the high-fusion entropies of eutectic phases and large kinetic undercooling. The mean hardness and fracture toughness measured by an indentation technique are 17.5 GPa and 3.6 MPa m1/2, respectively. The increase of fracture toughness can be attributed to the refinement of eutectic phases which restrain and arrest crack propagations.
AB - Rapid solidification of Al2O3/Y3Al5O12 (YAG) binary eutectic ceramic in situ composites during the remelting process using high-energy laser, which results in refinement of the solidification microstructure and improvement of the mechanical properties, is studied in this paper. The rapidly solidified Al2O3/YAG eutectic consists of Al2O3 and YAG phases without any other phases, effectively avoiding grain boundaries. The eutectic interspacing is extremely refined due to the high-temperature gradient and solidification rate of laser rapid solidification, and the minimal interspacing is as fine as 0.5 μm. The eutectic exhibits an obvious faceted-faceted eutectic growth characteristic which mainly derives from the high-fusion entropies of eutectic phases and large kinetic undercooling. The mean hardness and fracture toughness measured by an indentation technique are 17.5 GPa and 3.6 MPa m1/2, respectively. The increase of fracture toughness can be attributed to the refinement of eutectic phases which restrain and arrest crack propagations.
KW - AlO/YAlO (YAG)
KW - Eutectic ceramic in situ composite
KW - Fracture toughness
KW - High-temperature gradient
KW - Laser rapid solidification
UR - http://www.scopus.com/inward/record.url?scp=40749151811&partnerID=8YFLogxK
U2 - 10.1016/j.msea.2007.06.080
DO - 10.1016/j.msea.2007.06.080
M3 - 文章
AN - SCOPUS:40749151811
SN - 0921-5093
VL - 479
SP - 380
EP - 388
JO - Materials Science and Engineering: A
JF - Materials Science and Engineering: A
IS - 1-2
ER -