2004 Fiscal Year Final Research Report Summary
Rheo-extrusion of high-strength aluminum alloys using semi-solid slurry made by solidification-rate controlling technique
| Project/Area Number |
15560644
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Metal making engineering
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| Research Institution | Toyama Prefectural University |
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Principal Investigator |
UETANI Yasuhiro Toyama Prefectural University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (60099405)
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| Project Period (FY) |
2003 – 2004
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| Keywords | semi-solid slurry / rheo-extrusion / Al-10%Mg alloy / 7075 aluminum alloy / 2014 aluminum alloy / extrudability / tensile property / agw-hardening |
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| Research Abstract |
Rheo-extrusion process of high strength 7075 and 2014 aluminum alloys has been tried to develop utilizing their semi-solid slurries made by an easy and unique method, because this process has some great advantages such as saving energies and low lost in contrast to the thixo-extrution process. At first, low ductility (resulted in low strength), which occurs in the materials thixo-extruded at relatively higher speeds and then may also be caused in rheo-extruded ones, could be improved by an adequate forced-air cooling at forward position of die out-let in the thixo-extrusion tests using Al-10%Mg and 7075 alloys. The author used a simple device made of a thin SUS upright tube followed by a certain length of inclined water-cooled tube to make semi-solid slurries of 2014 and 7075 alloys. After many trials, especially in the latter alloy, semi-solid slurries containing solid particles with mean diameter of less than 50μm could be obtained under the condition feeding the melt, which had been cooled to slightly above liquidus temperature by passing down through the upright tube, into the water-cooled tube at forced high pressure. Semi-solid slurries of 7075 and 2014 alloys with various mean diameters of solid particles ranging 110 to 50μm were directly introduced within an extrusion container and then extruded to round bars at given temperatures, extrusion ratios of 25 to 100 and ram speeds of 5 to 20mm/s. They could be extruded soundly at a few times less force and faster by an order of magnitude than those of hot-extrusion. In the usages of 7075 alloy semi-solid slurries containing the finest solid particles, the bars rheo-extruded at 560℃, extrusion ratio of 36 and ram speed of 10mm/s showed the favorable tensile elongation, strength and age-hardenability equivalent to those of hot-extruded one.
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Research Products
(7 results)
