Mechanical Properties of Cold-Rolled and Annealed Al–12%Mg Alloy Sheet with High Mg Solid Solubility Fabricated from Vertical-Type High-Speed Twin-Roll Cast Strip

Si ranging from 0.2 mass% to 2.0 mass% was added to Al-5%Mg alloy (5182) and strip was cast by a vertical type high-speed twin-roll caster at a speed of 80 m/min. The as-cast strip was cold-rolled down to 1 mm thickness and annealed. The mechanical properties were investigated using cup tests and tension tests. The limiting draw ratio (LDR) of the 5182 alloy was 2.0 and the LDR became smaller as the Si content increased. When the Si content was 2.0 mass%, the LDR was 1.8, which shows that Si-added 5182 can be used for sheet forming, if the Si content is less than 2.0 mass%. The tensile strength and elongation were almost constant when the Si content was less than 1 mass%, but decreased at 2.0 mass% Si. However, the elongation was greater than 20% at 2.0 mass% Si. For die casting, 2.0 mass% Si was determined as the appropriate content from the results of the tension tests. When the Si content is in the range from 1.0 mass% to 2.0 mass%, then the Si added Al-5%Mg has the ability to be used for both die casting and sheet forming.

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Microstructure and mechanical properties of high-manganese-containing high-speed twin-roll cast Al-Mn-Si alloy strips and their cold-rolled sheets

MATEC Web of Conferences ◽

10.1051/matecconf/202032606004 ◽

2020 ◽

Vol 326 ◽

pp. 06004

Author(s):

T.Ha Nguyen ◽

Ram Song ◽

Yohei Harada ◽

Shinji Muraishi ◽

Shinji Kumai ◽

...

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

High Speed ◽

Solid Solution Hardening ◽

Columnar Dendrite ◽

Dispersion Hardening ◽

High Manganese ◽

Solution Hardening ◽

Cold Rolled ◽

Twin Roll

Al-Mn based alloys with high-manganese content are expected to have improved mechanical properties due to solid solution hardening and/or dispersion hardening. However, the increase of Mn solubility of the alloy is difficult by using the conventional DC casting. In order to solve this problem, in the present study, we focused on the twin-roll casting method which is characterized by high cooling rates. Several kinds of high Mn-containing Al-Mn-Si alloy strips were fabricated by using a vertical-type high-speed twin-roll caster equipped with a pair of water-cooled copper rolls. Direct temperature measurement of the liquid melt during the casting was also performed. The alloy strips of various compositions containing up to 4 Mn and 2 Si (wt%) were successfully obtained. By observing the microstructure of the cross section of the strip, we found the characteristic solidified structure. The solidified structure consisted of three layers. Two solidified shells with a columnar dendrite structure grew from the roll surfaces toward the strip center. In the mid-thickness region, the band structure consisting of equiaxed dendrites and globular grains was observed between the solidified shells. Very fine primary particles were observed in the matrix near the strip surface, while, relatively coarse particles with blocky and needle-like shape were observed in the central band of the as-cast strip. The electric conductivity measurement was performed for the as-cast strips. Mn solubility in Al matrix was estimated from the obtained values. The estimated Mn solubility in the Al-2Mn-xSi strips was between 1.5 ~ 1.8wt% Mn. It was over 1.43wt%Mn for the Al-4Mn-xSi strips. We found that the Mn solubility of the as-cast strips was considerably high. The strips were cold-rolled to the sheets and then annealed at various conditions. They were subjected to the tensile tests, and the effects of solid solution hardening and dispersion hardening are discussed.

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Twin-Roll Cast Al-Clad Magnesium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.618-619.467 ◽

2009 ◽

Vol 618-619 ◽

pp. 467-470 ◽

Cited By ~ 5

Author(s):

A.K. Prasada Rao ◽

K.H. Kim ◽

J.H. Bae ◽

Geun Tae Bae ◽

Dong Hyuk Shin ◽

...

Keyword(s):

Reaction Zone ◽

Transverse Section ◽

Intermetallic Phases ◽

Alloy Sheet ◽

Mg Alloy ◽

Microstructural Investigation ◽

Twin Roll Casting ◽

Roll Casting ◽

Twin Roll Cast ◽

Twin Roll

An attempt has been made to clad Mg alloy with Al by twin-roll casting. This was done by inserting an Al sheet between the roll and the Mg alloy melt during twin-roll casting. Microstructural investigation across the transverse section of the as-cast Al-clad Mg alloy sheet reveals a very good interfacial bonding between Al and the base Mg alloy. Annealing of the Al-clad Mg alloy sheet results in the formation of layers of various intermetallic phases along the Mg/Al interface. Subsequent rolling of the as-annealed sheet significantly improves the formability of the reaction zone, as evidenced by the cracking of the base Mg alloy before the cracking of the reaction zone.

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High Speed Roll Casting of Aluminum Alloy Strip

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.343 ◽

2005 ◽

Vol 475-479 ◽

pp. 343-348 ◽

Cited By ~ 5

Author(s):

Ryoji Nakamura ◽

Hisaki Watari ◽

Shinji Kumai

Keyword(s):

Mechanical Properties ◽

High Speed ◽

The Other ◽

Alloy Strip ◽

Cast Ingot ◽

Cast Strip ◽

Cooling Slope ◽

Roll Casting ◽

Twin Roll Caster ◽

Twin Roll

Two kinds of roll casters, which were suitable for high speed roll casting, were devised. One was a vertical type twin roll caster, and the other was an unequal diameter twin roll caster. The semisolid roll casting using a cooling slope was adopted to these roll casters. The solid fraction was smaller than 5%. 3 mm thickness of 6111 strip was cast at 60 m/min by the vertical type twin roll caster, and 5 mm thickness of 6111 strip was cast at 30 m/min by the unequal diameter twin roll caster. The microstructure of the as-cast strip was equiaxed and spherical, not columnar. The mechanical properties of the strip rolled from roll-cast strip were almost as same as that of the strip made from cast ingot.

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Roll Casting of Al-SiCp Strip

Materials Science Forum ◽

10.4028/www.scientific.net/msf.675-677.811 ◽

2011 ◽

Vol 675-677 ◽

pp. 811-814 ◽

Cited By ~ 1

Author(s):

Toshio Haga ◽

Teppei Nakamura ◽

S. Kumai ◽

H. Watari

Keyword(s):

Hot Rolling ◽

High Speed ◽

Strip Casting ◽

Cast Strip ◽

Fine Grain ◽

Roll Casting ◽

Speed Up ◽

Cold Rolled ◽

Twin Roll Caster ◽

Twin Roll

The strip casting of Al-SiCp alloy was operated by a high speed twin roll caster. The content of SiCp was 20Vol% and 30Vol%. Both of Al-20Vol%SiCp and Al-30Vol%SiCp strips could be cast continuously at the speed up to 90m/min. The SiCp particle distributed uniformly. This was the effect of fine grain of the strip. The as-cast strip of Al-20Vol%SiCp could be cold rolled after homogenization. The as-cast strip of Al-30Vol%SiCp could be cold rolled after once hot rolling and annealing. The as-cast strip of Al-20Vol%SiCp could be coiled at the diameter of 460mm.

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Center Segregation and Cross-Hatched Surface Pattern of Vertical-Type High-Speed Twin-Roll Cast Al–Si–Mg Alloy Strip Formed by Wide Rolls

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.f-m2019822 ◽

2019 ◽

Vol 60 (8) ◽

pp. 1643-1650

Author(s):

Tomoo Goda ◽

Shinji Kumai

Keyword(s):

High Speed ◽

Mg Alloy ◽

Surface Pattern ◽

Alloy Strip ◽

Twin Roll Cast ◽

Twin Roll

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Application of Vertical-Type High-Speed Twin-Roll Casting for Up-Grade Recycling and Clad Sheets Fabrication of Aluminum Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.877.56 ◽

2016 ◽

Vol 877 ◽

pp. 56-61 ◽

Cited By ~ 2

Author(s):

Shinji Kumai ◽

Yusuke Takayama ◽

Ryoji Nakamura ◽

Daisuke Shimosaka ◽

Yohei Harada ◽

...

Keyword(s):

Mechanical Properties ◽

Aluminum Alloy ◽

High Speed ◽

Cast Aluminum Alloy ◽

Cast Aluminum ◽

Casting Method ◽

Twin Roll Casting ◽

Roll Casting ◽

Twin Roll Cast ◽

Twin Roll

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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