Low-fuming, free-flowing fluxes for sherardising

摘要

Low-fuming, free-flowing fluxes for sherardising contain from 50 to 90% by weight of alkali metal chlorides and from 10 to 50% by weight of ammonium chloride. In addition they contain, based on the ammonium chloride and alkali metal chloride content, from 0.1 to 1% by weight of magnesium oxide and so much zinc chloride, that the weight ratio of magnesium oxide to zinc chloride is from 1 : 2 to 1 : 10.