The invention discloses a preparation method of an in-situ synthesized
mullite whisker toughened 90
alumina ceramic. The method consists of: taking 85-95wt% of highly dispersed alpha-
alumina powder and 5-15wt% of highly dispersed
silicon dioxide
powder as the raw materials, adopting
aluminum fluoride trihydrate
powder accounting for 4-18% of the weight of the raw materials and
dry basis titanium dioxide accounting for 0.5-3% of the weight of the raw materials as the catalysts, mixing the raw materials with the catalysts, then using water as the medium to perform ball-milling so as to form an Al2O3-SiO2 precursor containing AlF3 and TiO2, then adding
polyvinyl alcohol accounting for 1-3% of the weight of the raw materials to serve as the
adhesive, conducting mixing, then employing
spray drying process to perform
granulation and
ageing, then conducting isostatic pressing dry process forming, and performing high temperature firing so as to obtain the
mullite whisker toughened 90
alumina ceramic. According to the invention, adding of expensive
whiskers is unnecessary, a complicated dispersion process of additional adding of
whiskers is omitted, also the preparation process is simple, the obtained
whiskers have large length, high length-
diameter ratio and uniform dispersion, and the method is suitable for industrial production.