Method for fabricating an alumina body having nano-sized open-cell pores that are stable at high temperatures
A method for fabricating an alumina body having nano-sized open-cell pores, the alumina body is formed from α-Al 2 O 3 and Al(OH) 3 . The alumina body has porosity of greater than 36 percent by volume and a mean pore flow diameter less than 25 nm. The alumina body retains porosity of over 20 volume percent for temperatures up to 1510° C. for 1 hour. The nano-sized open-cell porous body can be scaled to any 3-dimensional structure.
1. A method of fabricating a ceramic body, comprising the steps of:
a) providing crystalline α-Al 2 O 3 particles having D50 of 0.4-0.6 micron and Gibbsite phase Al(OH) 3 particles of D50 of 5-6 microns;
b) combining and milling all of the particles;
c) granulating the milled particles;
d) forming a green compact of the granulated particles; and
e) sintering the green compact in a temperature range of 1316° C. to 1510° C.
2. A method as recited in claim 1 , wherein the sintering step e) is for 1 hour.
3. A method as recited in claim 1 , wherein the ceramic body has a porosity greater than 36 percent by volume when annealed at a temperature in the range of 1316° C. to 1400° C.
4. A method as recited in claim 1 , wherein the ceramic body has a porosity greater than 20 percent by volume when annealed at a temperature over 1350° C.
5. A method as recited in claim 1 , wherein the ceramic body has a mean pore flow diameter less than 25 nanometers.
6. A method as recited in claim 1 , wherein the α-Al 2 O 3 particles are in the range of 50-90 weight percent of the total α-Al 2 O 3 particles and Gibbsite phase Al(OH) 3 particles combined.