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:
Dec. 19, 1978
Filed:
Aug. 15, 1977
Edmondo Marianeschi, Terni, IT;
Sandro Basevi, Terni, IT;
Mario Barisoni, Albano Laziale (Rome), IT;
Paolo Marini, Rome, IT;
Carlo Borgianni, Rome, IT;
Roberto Ricci Bitti, Lanuvio (Rome), IT;
Centro Sperimentale Metallurgico S.p.A., Rome, IT;
Terni-Societa per l'Industria e l'Elettricita S.p.A., Rome, IT;
Abstract
An annealing separator for use on grain-oriented silicon steel strip comprises a magnesium oxide base composition containing rare earth metal oxides. The rare earth metal oxides are present in an amount of 0.8 to 30% by weight of the composition; but in the lower range of 0.8 to 5% by weight, and preferably up to 7% by weight, the oxides have a particle size of less than 325 mesh, and a fraction of 35-55% by weight smaller than 500 mesh. Alkali metal silicate may be present in an amount 5 to 45% by weight. Strip coated with annealing separator of the invention is characterized in that the coating is almost totally free of surface cavities, in that the denitriding and desulfuring rates are greatly accelerated, in that the surface resistivity of the coating is substantially increased, and in that the coating adheres more strongly to the strip.