The Experts below are selected from a list of 2499 Experts worldwide ranked by ideXlab platform
Toshiji Mukai - One of the best experts on this subject based on the ideXlab platform.
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microstructure and mechanical properties of Az91 Alloy produced with ultrasonic vibration
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yoshiaki Osawa, Susumu Takamori, Toshiji MukaiAbstract:Ultrasonic vibration was introduced into the solidification of the Az91 magnesium Alloy. The coarse dendrite microstructure solidified in the Az91 Alloy without any ultrasonic vibration. However, the microstructure with fine uniform non-dendrite grains was achieved with ultrasonic vibration. According to the analysis of refinement mechanism, it indicated that due to the acoustic cavitation and flows induced by ultrasonic vibration, the most of insoluble impurity particles become active as nucleation centers and the temperature gradient near the solidification front increases, which led to the fine uniform microstructure. Besides, the Az91 Alloy produced with ultrasonic vibration exhibited the improved mechanical properties at room temperature, such as compressive yield strength (94 MPa), ultimate compressive strength (376 MPa) and fracture strain (22.0%).
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grain refinement of Az91 Alloy by introducing ultrasonic vibration during solidification
Materials Letters, 2008Co-Authors: Yoshiaki Osawa, Susumu Takamori, Toshiji MukaiAbstract:Ultrasonic vibration was introduced into the solidification of Az91 Alloy. Various microstructures were produced in this Alloy using ultrasonic vibrations at different temperatures of the melt. The coarse dendrite microstructures were obtained with ultrasonic vibrations at temperatures below the liquidus temperature. The fine uniform grains were achieved under ultrasonic vibrations during the nucleation stage, which was mainly attributed to the cavitation and the acoustic flow induced by the ultrasonic vibration.
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Casting Surface of Az91 Alloy and Its Reaction with Sand Mold
Materials Transactions, 2008Co-Authors: Susumu Takamori, Yoshiaki Osawa, Takashi Kimura, Toshiji MukaiAbstract:Due to its light weight and abundance as a resource, the utilization of magnesium is increasing. Az91 Alloy is the most common cast magnesium Alloy and is widely used as die-casting material. Az91 is also used for sand mold casting. In sand mold casting, reaction with mold sand is expected because magnesium is a very reactive element. This study investigated the surface condition of Az91 castings using sand mold. Higher pouring temperature promoted the reaction with silica sand, and the surface of castings became rough. Reacting with mold sand, Mg 2 Si and Mg and Al complex oxides were precipitated near the casting surface.
Yoshiaki Osawa - One of the best experts on this subject based on the ideXlab platform.
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microstructure and mechanical properties of Az91 Alloy produced with ultrasonic vibration
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yoshiaki Osawa, Susumu Takamori, Toshiji MukaiAbstract:Ultrasonic vibration was introduced into the solidification of the Az91 magnesium Alloy. The coarse dendrite microstructure solidified in the Az91 Alloy without any ultrasonic vibration. However, the microstructure with fine uniform non-dendrite grains was achieved with ultrasonic vibration. According to the analysis of refinement mechanism, it indicated that due to the acoustic cavitation and flows induced by ultrasonic vibration, the most of insoluble impurity particles become active as nucleation centers and the temperature gradient near the solidification front increases, which led to the fine uniform microstructure. Besides, the Az91 Alloy produced with ultrasonic vibration exhibited the improved mechanical properties at room temperature, such as compressive yield strength (94 MPa), ultimate compressive strength (376 MPa) and fracture strain (22.0%).
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grain refinement of Az91 Alloy by introducing ultrasonic vibration during solidification
Materials Letters, 2008Co-Authors: Yoshiaki Osawa, Susumu Takamori, Toshiji MukaiAbstract:Ultrasonic vibration was introduced into the solidification of Az91 Alloy. Various microstructures were produced in this Alloy using ultrasonic vibrations at different temperatures of the melt. The coarse dendrite microstructures were obtained with ultrasonic vibrations at temperatures below the liquidus temperature. The fine uniform grains were achieved under ultrasonic vibrations during the nucleation stage, which was mainly attributed to the cavitation and the acoustic flow induced by the ultrasonic vibration.
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Casting Surface of Az91 Alloy and Its Reaction with Sand Mold
Materials Transactions, 2008Co-Authors: Susumu Takamori, Yoshiaki Osawa, Takashi Kimura, Toshiji MukaiAbstract:Due to its light weight and abundance as a resource, the utilization of magnesium is increasing. Az91 Alloy is the most common cast magnesium Alloy and is widely used as die-casting material. Az91 is also used for sand mold casting. In sand mold casting, reaction with mold sand is expected because magnesium is a very reactive element. This study investigated the surface condition of Az91 castings using sand mold. Higher pouring temperature promoted the reaction with silica sand, and the surface of castings became rough. Reacting with mold sand, Mg 2 Si and Mg and Al complex oxides were precipitated near the casting surface.
Susumu Takamori - One of the best experts on this subject based on the ideXlab platform.
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microstructure and mechanical properties of Az91 Alloy produced with ultrasonic vibration
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yoshiaki Osawa, Susumu Takamori, Toshiji MukaiAbstract:Ultrasonic vibration was introduced into the solidification of the Az91 magnesium Alloy. The coarse dendrite microstructure solidified in the Az91 Alloy without any ultrasonic vibration. However, the microstructure with fine uniform non-dendrite grains was achieved with ultrasonic vibration. According to the analysis of refinement mechanism, it indicated that due to the acoustic cavitation and flows induced by ultrasonic vibration, the most of insoluble impurity particles become active as nucleation centers and the temperature gradient near the solidification front increases, which led to the fine uniform microstructure. Besides, the Az91 Alloy produced with ultrasonic vibration exhibited the improved mechanical properties at room temperature, such as compressive yield strength (94 MPa), ultimate compressive strength (376 MPa) and fracture strain (22.0%).
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grain refinement of Az91 Alloy by introducing ultrasonic vibration during solidification
Materials Letters, 2008Co-Authors: Yoshiaki Osawa, Susumu Takamori, Toshiji MukaiAbstract:Ultrasonic vibration was introduced into the solidification of Az91 Alloy. Various microstructures were produced in this Alloy using ultrasonic vibrations at different temperatures of the melt. The coarse dendrite microstructures were obtained with ultrasonic vibrations at temperatures below the liquidus temperature. The fine uniform grains were achieved under ultrasonic vibrations during the nucleation stage, which was mainly attributed to the cavitation and the acoustic flow induced by the ultrasonic vibration.
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Casting Surface of Az91 Alloy and Its Reaction with Sand Mold
Materials Transactions, 2008Co-Authors: Susumu Takamori, Yoshiaki Osawa, Takashi Kimura, Toshiji MukaiAbstract:Due to its light weight and abundance as a resource, the utilization of magnesium is increasing. Az91 Alloy is the most common cast magnesium Alloy and is widely used as die-casting material. Az91 is also used for sand mold casting. In sand mold casting, reaction with mold sand is expected because magnesium is a very reactive element. This study investigated the surface condition of Az91 castings using sand mold. Higher pouring temperature promoted the reaction with silica sand, and the surface of castings became rough. Reacting with mold sand, Mg 2 Si and Mg and Al complex oxides were precipitated near the casting surface.
Sh Mirdamadi - One of the best experts on this subject based on the ideXlab platform.
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Effects of calcium and rare earth elements on microstructure and creep properties of Az91 Alloy in as cast and semisolid processed conditions
International Journal of Cast Metals Research, 2011Co-Authors: Bahram Nami, H Razavi, S G Shabestari, Seyyed Mehdi Miresmaeili, Sh MirdamadiAbstract:The effect of Ca and rare earth (RE) elements on the microstructure and creep properties of Az91 magnesium Alloy was studied in as cast and semisolid processed conditions. The results showed that in as cast condition of Az91 Alloy grain refinement takes place and the amount of β‐Mg17Al12 intermetallic phase decreases due to addition of Ca and RE elements. Also, two new Al11RE3 and Al2Ca intermetallic compounds are formed in the Ca and RE containing Alloy. In the semisolid microstructure, the size and shape factor of the primary globular α‐Mg phase and the size of the α‐Mg grains formed during secondary solidification decrease by adding Ca and RE elements into Az91 Alloy. It was also shown that the creep properties of Az91 Alloy is greatly improved by adding Ca and RE elements in the as cast and semisolid processed specimens.
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effect of ca re elements and semi solid processing on the microstructure and creep properties of Az91 Alloy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2011Co-Authors: Bahram Nami, H Razavi, Sh Mirdamadi, S G Shabestari, Seyyed Mehdi MiresmaeiliAbstract:Abstract The effects of calcium and rare earth elements (RE) on the microstructure and creep properties of as-cast and thixoformed Az91 magnesium Alloy have been investigated. It has been shown that the amount of β(Mg17Al12) intermetallic compound decreases by adding Ca and RE elements into Az91 Alloy and new Al11RE3 and Al2Ca intermetallic compounds form in the microstructure. The coarsening of primary α(Mg) particles in Az91 Alloy and in the Ca and RE containing (AZRC91) Alloy takes place by Ostwald ripening mechanism. Adding Ca and RE elements into Az91 Alloy results in a decrease in the coarsening rate of solid particles in semi-solid slurry, whereas it has no visible effect on the shape factor of the solid-particles. The creep properties of Az91 Alloy are improved by adding Ca and RE elements particularly, in the thixoformed condition.
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the effect of rare earth elements on the kinetics of the isothermal coarsening of the globular solid phase in semisolid Az91 Alloy produced via sima process
Journal of Alloys and Compounds, 2010Co-Authors: Bahram Nami, H Razavi, S G Shabestari, Seyyed Mehdi Miresmaeili, Sh MirdamadiAbstract:Abstract In the present study, the effects of rare earth (RE) elements on the microstructure and coarsening kinetics of the solid globular particle in the semisolid slurry of Az91 magnesium Alloy have been studied at 570 °C and 580 °C. The results showed that the coarsening kinetics of the solid globular particles in semisolid slurry of Az91 Alloy satisfies the Ostwald ripening theory. It was shown that the coarsening rate of the solid particles decreases by adding RE elements into Az91 Alloy, specially at 580 °C, which results in the smaller particles size. It was attributed to the solid–liquid interfacial energy reduction due to the addition of RE elements.
Bahram Nami - One of the best experts on this subject based on the ideXlab platform.
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Effects of calcium and rare earth elements on microstructure and creep properties of Az91 Alloy in as cast and semisolid processed conditions
International Journal of Cast Metals Research, 2011Co-Authors: Bahram Nami, H Razavi, S G Shabestari, Seyyed Mehdi Miresmaeili, Sh MirdamadiAbstract:The effect of Ca and rare earth (RE) elements on the microstructure and creep properties of Az91 magnesium Alloy was studied in as cast and semisolid processed conditions. The results showed that in as cast condition of Az91 Alloy grain refinement takes place and the amount of β‐Mg17Al12 intermetallic phase decreases due to addition of Ca and RE elements. Also, two new Al11RE3 and Al2Ca intermetallic compounds are formed in the Ca and RE containing Alloy. In the semisolid microstructure, the size and shape factor of the primary globular α‐Mg phase and the size of the α‐Mg grains formed during secondary solidification decrease by adding Ca and RE elements into Az91 Alloy. It was also shown that the creep properties of Az91 Alloy is greatly improved by adding Ca and RE elements in the as cast and semisolid processed specimens.
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effect of ca re elements and semi solid processing on the microstructure and creep properties of Az91 Alloy
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2011Co-Authors: Bahram Nami, H Razavi, Sh Mirdamadi, S G Shabestari, Seyyed Mehdi MiresmaeiliAbstract:Abstract The effects of calcium and rare earth elements (RE) on the microstructure and creep properties of as-cast and thixoformed Az91 magnesium Alloy have been investigated. It has been shown that the amount of β(Mg17Al12) intermetallic compound decreases by adding Ca and RE elements into Az91 Alloy and new Al11RE3 and Al2Ca intermetallic compounds form in the microstructure. The coarsening of primary α(Mg) particles in Az91 Alloy and in the Ca and RE containing (AZRC91) Alloy takes place by Ostwald ripening mechanism. Adding Ca and RE elements into Az91 Alloy results in a decrease in the coarsening rate of solid particles in semi-solid slurry, whereas it has no visible effect on the shape factor of the solid-particles. The creep properties of Az91 Alloy are improved by adding Ca and RE elements particularly, in the thixoformed condition.
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the effect of rare earth elements on the kinetics of the isothermal coarsening of the globular solid phase in semisolid Az91 Alloy produced via sima process
Journal of Alloys and Compounds, 2010Co-Authors: Bahram Nami, H Razavi, S G Shabestari, Seyyed Mehdi Miresmaeili, Sh MirdamadiAbstract:Abstract In the present study, the effects of rare earth (RE) elements on the microstructure and coarsening kinetics of the solid globular particle in the semisolid slurry of Az91 magnesium Alloy have been studied at 570 °C and 580 °C. The results showed that the coarsening kinetics of the solid globular particles in semisolid slurry of Az91 Alloy satisfies the Ostwald ripening theory. It was shown that the coarsening rate of the solid particles decreases by adding RE elements into Az91 Alloy, specially at 580 °C, which results in the smaller particles size. It was attributed to the solid–liquid interfacial energy reduction due to the addition of RE elements.
