EP0208801A1
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Corrosion resistant silicon nitride bodies
Assignee: Osram Sylvania Inc
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Filing: 1985-07-16
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Granted: —
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Expires: 2005-07-16
Abstract
Abstract Corrosion resistant silicon nitride bodies are produced from a composition of lanthanum oxide, aluminium oxide, and relatively impure silicon nitride.
Inventors
- 👤 Martin Y. Hsieh
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 03:10
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
61 words
A silicon nitride body consisting essentially of, in percent by weight: from about 3% to about 18% lanthanum oxide, from about 0.5% to about 5% aluminum oxide, up to about 2% iron, and up to about 0.25% each of carbon, calcium, aluminum or their oxides, and the balance silicon nitride, said body having a relatively high resistance to phosphoric acid corrosion.
Claim 2
Dependent Claim
61 words
A silicon nitride body consisting essentially of, in percent by weight: from about 3% to about 18% lanthanum oxide, from about 0.5% to about 5% aluminum oxide, up to about 2% iron, and up to about 0.25% each of carbon, calcium, aluminum or their oxides, and the balance silicon nitride, said body having a relatively high resistance to phosphoric acid corrosion.
Claim 3
Dependent Claim
49 words
A silicon nitride body according to Claim 1 consisting essentially of, in percent by weight: from about 1% to about 5% aluminum oxide, from about 3% to about 15% lanthanum oxide and the balance silicon nitride, and the atomic ratio of lanthanum to aluminum of about 1 to 1.
Claim 4
Dependent Claim
36 words
A silicon nitride body according to Claim 1 consisting essentially, of in percent by weight: from about 0.5 to about 4% aluminum oxide, from about 3% to about 12% lanthanum oxide and the balance silicon nitride.
References Cited (Backward Citations)
US4409003A
Cited
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