The round circular wires are mainly net-shaped into various profiled wires by rolling or drawing, to be further worked for electronic parts, springs, piston rings and rails. These processes require a large number of mill stands, roll passes or dies. Authors have developed a new type of compact continuous mill named the satellite mill. In this satellite mill rolling, longitudinal compressive stress significantly decreases the elongation and promotes transverse metal flow. This elongation-constrained effect of the satellite mill was confirmed in the previous study for rolling of flat and T-shaped profiled wires using open passes. In this study, the satellite mill with closed passes is applied to production of U-shaped and H-shaped profiled wires. The obtained rolling characteristics and hardness are compared with those by a conventional rolling method. It is shown that the satellite-mill rolling is able to form much higher ribs in products than a conventional rolling method and has advantage in the ability to fill the metal into the roll grooves. The elongation-constrained effect is more enhanced in using closed passes than open passes. This type of mill is considered to be suitable for production of profiled wires with complex cross sections.

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The authors have developed a new type rolling mill named the satellite mill. The mill comprises one large diameter roll (central roll) and five smaller diameter rolls (satellite rolls) arranged along a circumference of the central roll. Material is passed continuously through the five gaps between the central roll and the satellite rolls and deformed into a profiled cross section. Since all rolls are driven at the same roll speed, longitudinal compressive stress is produced between stands during rolling. The elongation is greatly suppressed. The mill has been applied to the production of round-edged flat wires and two kinds of T-shaped profiled wires from round circular wires. The obtained rolling characteristics and product properties are compared with those by a conventional rolling method. It is shown that the transverse metal flow is enhanced and the filling ability to the roll groove is excellent in satellite-mill rolling. The effect is more apparent in rolling of T-shaped wire having thinner ribs. It is supposed that the satellite mill is favorable for profiled wire production.

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A rolling method to increase the width of materials would have advantages in multi-width strip production, yield efficiency, productivity and texture control. The authors proposed a new method for spread rolling of thin and wide strip. The method employs 3-pass caliber rolling, where several portions of the width are reduced. In this study, the method was applied to commercial 1050 Aluminum strips. Necking or fracture occurred at thin portions near edges. In order to prevent the occurrence of defects, the method is improved to the 5-pass rolling method. It is found that the 5-pass rolling is effective in lateral spread as well as in preventing in defects formation. Thin aluminum strips with an aspect ratio (width/thickness) of 100 are successfully widened up to 3% by 30%–reduction rolling. As for the mechanical properties of rolled strips, the spread strips are slightly work-hardened than those of the flat strip. Development of rolling texture is not so remarkable in the spread strips as that in the flat-rolled strips. It is concluded that the proposed spread rolling method can control the texture as well as the width of rolled strips.

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Most industrial products and components have been made of steel or another monolithic material. Recently, multi–material structure is often adopted to improve the performance. In the multi–material design, a few constituent materials should be selected and configured at appropriate locations. However, the optimization method has not been well established. With changing material properties intensively, further optimization is supposed to be possible. The authors propose the multi–property design method, where a material having prescribed properties is fabricated on demand. In this study, cold extrusion of multi–filament billets, where copper, iron, and aluminum filaments and copper sheath were used, was conducted. By changing materials and numbers of filaments to insert, three properties (density, yield strength, electrical resistivity) of extruded bars were controlled. As the measured three properties are close to the predictions by the mixture rule, the multi–property design is found to be feasible by the cold extrusion.

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