| eutectic ceramic with a high melting point and good thermal shock resistance, is expected to become a new generation of ultra-high-temperature structural materials. It can greatly improve the temperature of turbine blade forefront which may effectively improve the thrust-weight ration of engine, thus, great social and economic benefits may be gained. In this paper, temperature field and fluid field during zone-melting process have been simulated by MARC finite element analysis. And Al2O3/MgAl2O4/ZrO2 eutectic ceramic has been prepared by zone-melting method. Main research contents and conclusions are as follows.Effects of different crucible materials (tungsten, molybdenum and graphite) on temperature field during eutectic ceramic praperation have been researched. Molybdenum is chosen as the ideal crucible material by comprehensive analysis of factors containing temperature distribution, melting zone length, temperature gradients and chemical nature.Effects of parameters (crucible temperature and growth rates) on solid-liquid interface morphology and evolution of solid-liquid interface morphology during different growth stage have been simulated. As the crucible wall temperature increases from 2080℃to 2290℃, solid-liquid interface transits from a convex interface to a flat interface, and then transits from a flat interface to a concave interface when crucible temperature is higher than 2190℃. The temperature gradient of solid-liquid interface inceases greatly as the crucible wall temperature inceases. Temperature gradient of solid-liquid interface changes little between the center axis and the middle center of eutectic ceramic (30-50℃/cm), while significant changes appeared between the middle center and the edge of eutectic ceramic (250-320℃/cm). When the solid-liquid interface is flat interface, there is no significant change in morphology during the solidification process. When the solid-liquid interface is convex or concave interface, the protruding height or depression depth changes significantly at the end of the growth stage. Moreover, length of zone-melting increases during solidification process in any interface morphology. When the crucible radius is 4mm, the protrusion height of solid-liquid interface decreases as the growth rate reduces.Evolution of the flow chart during ACRT process and effects of process parameters on the convection strength have been discussed. The lower right corner and the central top of crucible maintains clockwise flow in the crucible rotation deceleration stage, while the central bottom and upper right corner of crucible keep counter-clockwise flow. And convection intensity become weaken as the rotation speed decreases. In the crucible reverse speed stage, a completely opposite flow field is presented, and convection intensity is enhanced as the rotation speed increasees. Moreover, convection intensity can be enhanced when crucible rotation accelerationωa, crucible maximum speedωmax, crucible radius r increases or constant time t2 become shorten.Al2O3/MgAl2O4ZrO2 eutectic ceramics have been prepared by ZM method on the basis of simulation result, and these organization and performance have been studied. When growth rate is 2mm/h, Al2O3/MgAl2O4ZrO2 eutectic ceramics have a dense organization without pores and amorphous phase, while a banded structure appears when the growth rate is 6mm/h. In addition, after a heat treatment in 1550℃for 15h, there is no obvious change in weight and grain size. Moreover, hardness and fracture toughness of this material are up to 17Gpa and 6.0MPa-m1/2 respectively, room temperature bending strength is 720MPa, which is up to 5 times of pre-sintered ceramics with same chemical constituent.
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