In order to improve the properties of silicon based ceramic core

the Al

2

O

3

fibers with different content were added to the core slurry

and the core was made by hot pressure casting.The change of the bending strength and porosity of the core with different Al

2

O

3

fibers was analyzed

and the microstructure of the sample was observed.The results show that the effect of Al

2

O

3

fiber on the flexural strength and porosity of the ceramic core is significant.With the fiber content of 1%

the core flexural strength reaches the maximum value of 20.48 MPa

and with the fiber content of 0.75%

the porosity of the core is 36.16%.However

with the fiber addition more than 1%

the fiber presents poor dispersion

and the fiber bridging action is weak

so the enhancement effect is weakened.Al

2

O

3

fiber reinforced ceramic core includes two mechanisms

bridging enhancement and pull-out enhancement.