Coatings for ferrous substrates
AssigneeMerck & Co., Inc.
InventorsLeonard S. Lee, Samuel W. Sopp, Howard M. Siegel
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Abstract
Coatings for silicon steel comprised of MgO, an amorphous magnesia-silica complex and a lithium bearing compound.
Claims2
A composition for coating magnetic ferrous material prior to the step of annealing said material comprising MgO, Mg(OH).sub.2 or mixtures thereof, at least one lithium compound and at least one magnesia-silica complex containing from about 0.001 to 2.0% by weight of an alkali metal oxide or hydroxide wherein the mole ratio of the MgO:SiO.sub.2 is from about 1:25 to 14:1, said magnesia-silica complex being amorphous as indicated by its X-ray powder diffraction pattern and exhibiting the following differential thermal behavior characteristics:
- an endothermic peak at about 250.degree.C., an exothermic peak at about 820.degree. and at about 980.degree.C.
Dependencies are inferred from the claim text.