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:
Aug. 23, 1983
Filed:
Dec. 21, 1981
Applicant:
Inventors:
Anthony P Moschetti, Acton, MA (US);
J Thomas Smith, Acton, MA (US);
Carr L Quackenbush, Acton, MA (US);
Helmut Lingertat, Dorchester, MA (US);
Vincent W Nehring, Stillwater, MN (US);
Assignee:
GTE Laboratories Incorporated, Waltham, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B32B / ; C04B / ;
U.S. Cl.
CPC ...
428332 ; 428446 ; 501 98 ; 501152 ;
Abstract
Sintered silicon nitride-silica-yttria ceramic articles having silica-rich or yttria-rich casing layers are disclosed. The surface layers are formed by sintering pre-compacted bodies in a powder setter bed to produce unitary sintered bodies having surface layers in which the atom ratio of yttrium to silicon has a smooth gradient from the surface of the article to the interior body of the article.