| Porous ceramics have become high-performance, the role of a unique and widely used ceramic materials because of its unique pore structure and special properties of ceramic itself. In order to adapt the development of biotechnology and the use of energy, and to control and improve the environment this century, the exploitation and application of porous ceramics will be developed rapidly. At present, among many properties of porous ceramic materials, the improvement in corrosion resistance has become one of the keys to accelerate development and application. The resistant to corrosion of porous ceramic materials is closely related to their composition and structure. In this study, the alumina ceramic was used as substrate. The resistant to corrosion of alumina substrate-ceramic has been improved by doping Cr3+ and Zr4+ ions.The Cr2O3, Zr(OH)4 and ZrO2 were added into alumina substrate, respectively. Then the factors that influence the properties of porous ceramics were investigated, including content of additives and sintering temperatures. The sintered samples were characterized by SEM, XRD, porosity,mass loss rate, bending strength, etc. The influence of the amount of doping Cr3+ and Zr4+on the porosity,mass loss rate of corrosive solution and impact bending strength of the samples before and after corrosion was discussed. The changes of microstructure of the samples before and after corrosion were analyzed. The mechanism of the corrosion of doping Cr3+ and Zr4+ in Al2O3 porous ceramic was also studied.According to large numbers of experiments, some conclusions have been drawn: (1) The high-sintering activity ZrO2 powders obtained by calcining Zr(OH)4 promote the coarseness of ZrO2 particles connected with Al2O3 particles and strengthen the neck-connect of Al2O3 particles, so the corrosion resistance has been improved. (2) The Cr2O3 and Al2O3 can form a continuous solid resistance at high temperatures, and the finer of the Cr2O3 particles introduced, more evenly dispersed, the better corrosion resistance. (3) The mass loss rate of the alumina porous samples doped with Cr3+ and Zr4+ increases with the concentration of etching solution and etching time, but the mass loss rate is relatively flat and significantly lower than that of comparison samples. (4) The etching rate of samples at 80℃is higher than that of room temperature, but the decrease of the flexural strength of samples after corrosion is relatively smaller than that of comparison samples. The results show that: the samples added with 2% Cr2O3, after sintered at 1600℃for 2h have the porosity of 38%. When the samples are etched by 80℃,5mol/L of HNO3 for 10h, the mass loss rate is 0.11%, which is 0.195% less than the original sample;The samples added with 10% Zr(OH)4 and 10% ZrO2, after sintered at 1550℃for 2h have the porosity of 35%, When the samples are etched by 5mol/L of HNO3 for 10h, the mass loss rate is 0.06%, which is 0.245% less than the original sample.
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