Continuous casting of light alloys - where ultrasonic transducer is partly immersed in melt in mould to produce castings with fine grain size and increased ductility

摘要

A molten light alloy is poured into a mould in which the melt is kept at 10-150 deg.C above its liquidus. An ultrasonic transducer is partly immersed in the melt to refine the latter and also to reduce the grain size in the cast billet. The transducer distributes uniform ultrasonic energy of 2-60 W/sq.cm. across the me and is immersed to a depth of W/12 to W/4, where W is the wavelength of the ultrasonic energy. To aid refining of the melt, a porous material may be immersed in the melt below the transducer, the distance between the material and the transducer being between W/12 and W/4. With the invention, the solid nonmetallic inclusions in the cast prod. are reduced by 50%, and its hydrogen content is reduced by 50 to 67%., as compared with similar prods. cast without using ultrasonic energy. The fine grain structure of the cast prods. increases their ductility.