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:
Jun. 20, 1978
Filed:
Mar. 05, 1976
Applicant:
Inventors:
Philippe M Galmiche, Clamart, FR;
Andre R Hivert, Pontoise, FR;
Andre M Walder, L'Hay-les-Roses, FR;
Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C23C / ;
U.S. Cl.
CPC ...
427247 ; 2915 / ; 148-63 ; 427250 ; 427252 ; 427253 ; 427300 ; 427401 ;
Abstract
A metal article having perforations therein whose transverse cross-sectional dimension is less than 0.4 mm has formed thereon a surface diffusion alloy by applying a refractory filter element to the workpiece surface prior to the diffusion treatment, the filter element being a refractory felt based on metal fibres including chromium in a proportion by weight of from 10 to 60%. The felt is oxidized to give a layer of chromium oxide. This is followed by conventional thermochemical powder diffusion treatment in the presence of at least one chromium oxide-reducing element selected from aluminium, yttrium, titanium and the lanthanides.