| 摘要 |
<p>1298409 Modifying steel surfaces ALLEGHENY LUDLUM INDUSTRIES Inc 18 Dec 1970 [2 Jan 1970] 60288/70 Heading C7U An electrically insulative coating is provided on an alloy having a high permeability and a low core loss by treating it with an aqueous solution containing 6-18 mole per cent ammonium ions, 21-63 mole per cent phosphate ions, 8-24 mole per cent chromate ions, and 15-45 mole per cent metal ions from at least one GpIIA metal, at least 1 mole per cent of said metal ions having resulted from the oxide, hydroxide, carbonate, bicarbonate, or chromate of said metal. The coated alloy is cured at 400-1900‹F for 2 seconds to 4 hours. Calcium and magnesium are the preferred metal ions. The alloy treated may be silicon-steel, and the coating is from 0À06 to 0À2 mils thick. Reference is made to Specification 1298410.</p> |
