Casting direct-chill

Zinc rolling slabs have been cast successfully by semicontinuous direct-chill casting methods. This is the preferred method for superplastic zinc alloys which, because of their large freezing range, display unacceptable surface shrinkage when cast in open molds. 

The casting methods used in aluminum forming can be divided into three classes direct chill casting, continuous casting, and stationary casting. 

Cooling water from direct chill casting... 

Direct chill casting or continuous rod casting Solution heat treatment Cleaning or etching... 

Summary of Pollutant Data for the Direct Chill Casting Subcategory Verification Data... 

Direct chill casting is the pouring of molten aluminum into a water-cooled mold. Contact cooling water is sprayed onto the aluminum as it is dropped into the mold, and the aluminum ingot falls into a water bath at the end of the casting process. 

Two examples may be used to illustrate the complexity of problems of this kind. When film is made by extrusion followed by casting on chill rolls there can be a tendency for the extruded web to shrink inwards towards the centre of the rolls—the phenomenon known as neck-in . The edge of film concerned becomes thicker than the rest. It has been found that more elastic melts, capable of keeping a tension in the direction of extrusion, are less liable to exhibit this fault. 

Some heats were cast directly into chills without runners. Ten casts were made for each alloy in cylinders 50 mm. in diameter and 50 mm. in length. 

Two alloys, the chemical compositions of which are shown in Table 3, were produced by continuous direct chill (DC) casting in Wagstaff, Inc., Spokane, WA. The cast billets had 76 mm diameter and 4 m length. Blanks of 150 mm long were cut from the billets and homogenized at 733K for up... 

Reddy AV, Beckermann C (1997) Modeling of macrosegregation due to thermosolutal convection and contraction-driven flow in direct chill continuous casting of an Al-Cu round ingot. Metall Mater Trans B 28 479- 89... 

DC direct chill (casting) GB gain X bandwidth (product)... 

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