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Structural ceramic (also named Engineering ceramic) is a
newly developedmaterial. Compared with metal for structure, it
demonstrates manyexcellent physical and mechanical properties.
Such as low density, lowcoefficient of expansion,low heat
transfer coefficient, high Young'smodulus, high hardness, high
compress strength, and good corrosion, oxidization,and creep
resistance. Howrver, extreme brittleness is the primany
obstacleto its application in engineering. Alumina is the
typical material of ceramic. It is execellent for its high
srengthand good ability to resist corrosion and oxidization.
However,alumina alsopossess the weakness of low toughness.By
adding reinforcement, its strengthand toughness can be improved.
For example, the fracturetoughness can be increased by adding
the metallic reinforcement. However, theoxidization resistance
and the property of low density will be sacrificed.Therefore, it
will be a target for researchers to choose areinforcement that
will improve the weaknesses of the material and keep
itselementary properties at the same time. Owing to its low
density,easy to conduct heat, and excellent oxidization
resistance,NiAl is chosen as a reinforcement in this study. To
make a sample, we add NiAl particleinto alumina matrix evenly,
from the mixed powder into the initial sample bydie-pressing
method, and then sinter it in argon atmosphere at 1500℃.
After sintering and milling, we proceed the following
experiments: phase identificatinoby X-ray, measurement of
mechanical and physical properties (including density,flexural
strength, and fracture toughness)in room temperature, strength
and toughnessof the samples after oxidization, and properties of
the composite after thermalshock. By observing the
microstructure of the samples, We tempt to find out thecauses
that effect strength and toughness of the composit. Because
of the complexity of making ceramic materials and time
consumingprocess, we try to use the remaining material with
other materials glued toboth ends to reduced the processing time
and procedure.Thus, we can reusethe material and conduct the
experiments repeatedly. Meanwhile, we comparethe data with that
we got from experiment by standard sample. key words：fracture
toughness, NiAl metallic compound ,methanical properties,
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