The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 18, 1995
Filed:
Jul. 28, 1993
Tawei Sun, Blacksburg, VA (US);
Nancy R Brown, Christiansburg, VA (US);
Jesse J Brown, Jr, Christiansburg, VA (US);
The Center for Innovative Technology, Herndon, VA (US);
Virginia Polytechnic Institute & State University, Blacksburg, VA (US);
Abstract
.beta.-Al.sub.2 TiO.sub.5 protective coatings have been developed for both dense and porous ceramics such as SiC and Si.sub.3 N.sub.4 using a chemical solution processing method involving the hydrolysis and condensation of aluminum tri-sec butoxide and titanium butoxide. The solution viscosities, pH values, H.sub.2 O/alkoxide molar ratios, and dip coating withdrawal rates required for crack-free .beta.-Al.sub.2 TiO.sub.5 are 1.0 to 6.2 cP, pH 1-4.5, molar ratio 1.5-10, and withdrawal rate of 2.2-8.0 cm/min, respectively. Conversion of the amorphous coating to crystalline .beta.-Al.sub.2 TiO.sub.5 is achieved by a succession of calcination below 450.degree. C. and a final heat-treatment at 1300.degree. C. for ten hours with controlled heating and cooling rates.