EP0002918A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Method of treating a ceramic body prior to hot pressing and ceramic body thus treated; method of manufacturing a ceramic assembly, and ceramic assembly thereby produced
Assignee: Ford-Werke GmbH
•
Filing: 1978-12-18
•
Granted: —
•
Expires: 1998-12-18
Abstract
Abstract A process for preventing thecracking of ceramic bodies during a hot pressing operation comprises applying a relatively thin layer of a release material to surfaces of the ceramic body which are to be load reaction surfaces during the hot pressing operation. A relatively thick layer of the release material is applied to surfaces of the ceramic body which are not to be load reaction surfaces during the hot pressing operation.
Inventors
- 👤 Robert R. Baker
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 06:07
CPC Classifications
B; B28; B28B; B28B3/00; B28B3/02; B28B3/025; B22; B22F; B22F3/00; B22F3/12; B22F3/1208; B22F3/1216; C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C04B35/593; C04B35/622; C04B35/64; C04B35/645; F; F01; F01D; F01D5/00; F01D5/12; F01D5/28; F01D5/284
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
148 words
A method of treating a ceramic body to protect the body from cracking during a hot pressing operation in which pressure is applied to the body, the ceramic body having a portion thereof of complex shape defined by surfaces extending in different directions, the complex shaped portion of the body being supported by an encapsulating medium during the hot pressing operation, which method comprises the steps of applying a relatively thin layer of a release material to the surfaces of the ceramic body which are to be load reaction surfaces during the hot pressing operation, said release material being non-reactive with the ceramic body and encapsulating medium at the temperatures and pressures encountered in the hot pressing operation; and applying a relatively thick layer of said release material to the surfaces of the ceramic body which are not to be load reaction surfaces during the hot pressing operation.
Claim 2
Independent Claim
148 words
A method of treating a ceramic body to protect the body from cracking during a hot pressing operation in which pressure is applied to the body, the ceramic body having a portion thereof of complex shape defined by surfaces extending in different directions, the complex shaped portion of the body being supported by an encapsulating medium during the hot pressing operation, which method comprises the steps of applying a relatively thin layer of a release material to the surfaces of the ceramic body which are to be load reaction surfaces during the hot pressing operation, said release material being non-reactive with the ceramic body and encapsulating medium at the temperatures and pressures encountered in the hot pressing operation; and applying a relatively thick layer of said release material to the surfaces of the ceramic body which are not to be load reaction surfaces during the hot pressing operation.
Claim 3
Dependent Claim
40 words
A method according to Claim 1 wherein said relatively thin layer of release material has a thickness in a range of 0.001-0.003 inches and said relatively thick layer of release material has a thickness in the range from 0.005-0.010 inches.
Claim 4
Dependent Claim
18 words
A method according to Claim 1 or Claim 3 wherein the ceramic body is composed of silicon nitride.
Claim 5
Independent Claim
20 words
A method according to any one of Claims 1 to 3 wherein the release material is composed of boron nitride.
Claim 6
Independent Claim
68 words
A method of manufacturing a ceramic assembly which comprises forming a first ceramic body, encapsulating the body in a protective medium, bondingt second ceramic body to the first ceramic body in a hot pressing operation, and removing the protective medium, characterised in that the first ceramic body is treated in accordance with any one of Claims 1 to 4 prior to the application of the protective medium thereto.
Claim 7
Dependent Claim
17 words
A ceramic body which has been treated in accordance with any one of Claims 1 to 4.
Claim 8
Dependent Claim
11 words
A ceramic assembly produced by a method according to Claim 5.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.