Centerline Segregation in Twin-Roll-Cast Aluminum Alloy Slab

A horizontal-type twin roll casting method has been popular for producing aluminum alloy strips, however, it is characterized by a relatively low productivity (1~6 m/min). In contrast, a vertical-type high-speed twin-roll casting method possesses an extremely high productivity (60~120 m/min (1~2 m/s)) and an excellent heat extraction ability. The rapid cooling effect provided significant microstructure refinement and mechanical properties improvement in various kinds of cast aluminum alloy products. Not only “product to product recycling” but also “up-grade recycling” can be achieved by making good use of these merits. Two examples of application showing the potential of vertical-type high-speed twin roll casting method are presented. (1) Several kinds of Al-Si base alloy were cast into the strips. Not only strength and toughness but also formability was increased in the twin roll cast products. In particular, great improvement in deformability shows the potential of the twin-roll cast aluminum alloy products as substitutes for some wrought aluminum alloy products. (2) The vertical-type tandem twin-roll caster was able to fabricate a clad strip by single step. The A4045/A3003/A4045 aluminum alloy clad sheets produced by the twin-roll casting showed better mechanical properties than the conventional hot-roll bonded clad sheets.

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Centre Line Segregation in Twin Roll Cast Aluminum Alloy Slab

Essential Readings in Light Metals ◽

10.1007/978-3-319-48228-6_124 ◽

2016 ◽

pp. 981-988

Author(s):

I. Jin ◽

L. R. Morris ◽

J. D. Hunt

Keyword(s):

Aluminum Alloy ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Centre Line ◽

Twin Roll Cast ◽

Twin Roll

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Centre line Segregation in Twin Roll Cast Aluminum Alloy Slab

Essential Readings in Light Metals ◽

10.1002/9781118647783.ch124 ◽

2013 ◽

pp. 981-988

Author(s):

I. Jin ◽

L.R. Morris ◽

J.D. Hunt

Keyword(s):

Aluminum Alloy ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Centre Line ◽

Twin Roll Cast ◽

Twin Roll

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Globular Crystals in the Center of Roll Cast Aluminum Alloy Strips

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1007.34 ◽

2020 ◽

Vol 1007 ◽

pp. 34-40

Author(s):

Toshio Haga ◽

Maho Tsuchida ◽

Hirotaka Sakata ◽

Hisaki Watari ◽

Shinichi Nishida

Keyword(s):

Aluminum Alloy ◽

High Speed ◽

Strip Casting ◽

Cast Aluminum Alloy ◽

Thickness Direction ◽

Cast Aluminum ◽

Cooling Slope ◽

Roll Gap ◽

Twin Roll ◽

Center Area

This study investigated the crystallization position and formation mechanism of globular crystals at the center area in the thickness direction of aluminum alloy strips cast by a high-speed twin roll caster. Twin roll casters for single strips and clad strips were used, as well as twin roll casters equipped with a cooling slope. The globular crystals were formed from dividing arms of dendrites of the solidified layer facing the center area at the roll gap. The arms of isolated dendrite also divided. No globular crystals were formed at the interfaces of clad strips with different solidification temperatures because of the temperature gradient at the interface which inhibited division of the dendrite arms. It was demonstrated that globular crystals at the center area of the thickness direction were formed by dendrite-arm-dividing at the roll gap by the strip casting clad strip. Experiments by semisolid-strip casting with the cooling slope showed that globular crystals in the molten metal existed in the solidification layers.

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Elimination of edge cracks and centerline segregation of twin-roll cast aluminum strip by ultrasonic melt treatment

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2020.03.021 ◽

2020 ◽

Vol 9 (3) ◽

pp. 5034-5044 ◽

Cited By ~ 2

Author(s):

Jinxian Huang ◽

Jianguo Li ◽

Cong Li ◽

Chunfa Huang ◽

Bernd Friedrich

Keyword(s):

Cast Aluminum ◽

Centerline Segregation ◽

Melt Treatment ◽

Aluminum Strip ◽

Edge Cracks ◽

Ultrasonic Melt Treatment ◽

Twin Roll Cast ◽

Twin Roll

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Effect of Ultrasonic Field on Centerline Segregation of Cast Aluminum Alloy 7050 Ingots

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.66 ◽

2011 ◽

Vol 399-401 ◽

pp. 66-70 ◽

Cited By ~ 1

Author(s):

Xiao Qian Li ◽

Ding Xin Chen ◽

Ri Peng Jiang

Keyword(s):

Aluminum Alloy ◽

Ultrasonic Treatment ◽

Solid Solubility ◽

Solidification Process ◽

Ultrasonic Field ◽

Cast Aluminum Alloy ◽

Ultrasonic Power ◽

Cast Aluminum ◽

Segregation Index ◽

Centerline Segregation

By introducing ultrasonic field during the solidification process of aluminum alloy melt, the effects of ultrasonic treatment (UST) on macroscopic and microscopic segregation were investigated. The results show that under 170W of UST, the macrosegregation degree of Zn is diminished to the minimum, the segregation index reaches 0.0583. At a higher ultrasonic intensity, the UST greatly contributes to the positive centerline segregation in the ingot. Compared with conventional casting (without UST), the solid solubility of Zn, Cu and Mg inside crystals of ultrasonic casting can be strengthened so that the microsegregation tends to be minimized. Overall, the ultrasonic cavitation and acoustic stream promote the redistribution of solute elements in the ingots, and a reasonable ultrasonic power is beneficial to weaken the segregation.

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