Process of working metals coated with a protective coating

摘要: A process for protecting metal from the deleterious effects of interaction with atmospheres surrounding said which comprises forming on surface a continuous film green chromium oxide and silica, portion being directly bonded to underlying base coacting silica provide impervious gas at temperatures about 500 DEG C. 1300 The invention contemplates product so protected composition matter comprising powder dispersed in an alkali-stabilized sol particularly adapted be used oxide-silica metals.