The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform
Bo Wen Xiong - One of the best experts on this subject based on the ideXlab platform.
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Effect of synergistic action of ultrasonic vibration and solidification Pressure on tensile properties of vacuum Counter-Pressure casting aluminum alloy
China Foundry, 2018Co-Authors: Gang Lu, Bo Wen Xiong, Qiang-qiang ZhengAbstract:The effect of synergistic action of ultrasonic vibration and solidification Pressure on tensile properties of vacuum Counter-Pressure casting ZL114A alloys was studied systemically through testing and analyzing the tensile strength and elongation subjected to different ultrasonic powers and solidification Pressures. The results indicate that the synergistic action of ultrasonic vibration and solidification Pressure can result in the refinement of grains and improvement of tensile properties. Both the highest tensile strength and elongation of aluminum alloy were obtained under synergistic action of 600 W ultrasonic power and 350 kPa solidification Pressure. Moreover, the tensile fracture morphology shows obvious ductile fracture characteristics. When the solidification Pressure is lower than 300 kPa, the effect of ultrasonic power on tensile strength and elongation is more obvious, but when the solidification Pressure is higher than 300 kPa, the effect of solidification Pressure on tensile strength and elongation is greater. Meanwhile, the size and morphology of the eutectic silicon were improved significantly by the ultrasonic vibration and pressurized solidification. The strip and massive eutectic silicon phase are completely converted into small short rod-like and evenly distributed Si phases at the grain boundary of primary α-Al.
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Density and solidification feeding model of vacuum Counter-Pressure cast aluminum alloy under grade-pressuring conditions
China Foundry, 2016Co-Authors: Huan Yu, Bo Wen Xiong, Gang Lu, Suai XuAbstract:The density of vacuum Counter-Pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade Pressure difference and time on the density of aluminum alloys was discussed, and the solidification feeding model under grade-pressuring condition was established. The results indicate the grade-Pressured solidification feeding ability of vacuum Counter-Pressure casting mainly depends on grade Pressure difference and time. With the increase of grade Pressure difference, the density of all the aluminum alloy samples increases, and the trend of change in density from the pouring gate to the top location is first decreasing gradually and then increasing. In addition, in obtaining the maximum density, the optimal grade-pressuring time is different for samples with different wall thicknesses, and the solidification time when the solid volume fraction of aluminum alloy reaches about 0.65 appears to be the optimal beginning time for grade-pressuring.
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microstructures and mechanical properties of vacuum Counter Pressure casting a357 alloys solidified under grade pressurising effects of melt temperature
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2014Co-Authors: Bo Wen Xiong, Zhenjun Wang, Huan YuAbstract:Abstract The effects of the melt temperature on the relative densities, microstructures and mechanical properties of vacuum Counter-Pressure casting A357 alloys solidified under grade-pressurising (200 kPa) were investigated. The results indicated that the relative densities and mechanical properties of samples solidified under grade-pressurising were affected by the melt temperature (580–610 °C). The optimal relative density and mechanical properties were achieved at a melt temperature of 590 °C. The microstructures varied with the melt temperature as a result of the differences in the strengths of the feeding flow and dendrites. The powerful feeding flow caused by grade-pressurising solidification can induce stress on the dendrites, resulting in the collapse of the primary dendrite network to form equiaxed dendrites. Decreasing the feeding Pressure proportionally to the solid volume fraction was proposed to obtain a suitable melt temperature for improving the density and refining the microstructure.
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Effect of SF6 Concentrations on Protective Film of Vacuum Counter-Pressure Filling Molten Magnesium Alloy
Advanced Materials Research, 2013Co-Authors: Yang Zhen, Bo Wen Xiong, Gang Lu, Bai Ping LuAbstract:Through testing and analyzing Surface micromorphology of protective film and elemental composition and content of vacuum Counter-Pressure filling AZ91D magnesium alloy by SF6 mixed gas, the effect of SF6 concentrations on protective film of vacuum Counter-Pressure filling molten magnesium alloy was studied. The results show that SF6 concentrations have greater effect on protective film of molten magnesium alloy. With the increase of SF6 concentrations, surface micromorphology of protective filmof vacuum Counter-Pressure filling AZ91D magnesium alloy becomes more continuous and dense. Meanwhile, the mass fraction of F atom of the protective film is increased, and the content of O atom is decreased. Moreover, F/O atomic ratio increases significantly too, so MgF2 content of the protective film increases gradually. Therefore, protective effect of molten magnesium depends on F/O atomic ratio and MgF2 content of the protective film. When SF6 concentrations are greater than 4.8 , protective effect of molten magnesium is good.
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Study on the Grade-Controlled Filling of Vacuum Counter-Pressure Casting Thin Wall Aluminum Alloy
Advanced Materials Research, 2011Co-Authors: Huan Yu, Bo Wen Xiong, Jia Hui Wang, Zhi Feng XuAbstract:The grade-controlled filling behavior of vacuum Counter-Pressure casting thin wall aluminum alloy was studied by numerical simulation and experimental investigation. According to the analysis of filling behavior under fixed Pressure and the casting structure, the technology of the grade-controlled filling of vacuum Counter-Pressure casting thin wall aluminum alloy was suggested. The result shows that the filling velocity was controlled on grade, resulting in the smoothly and sequential filling behavior, and the decreasing of defects in castings.
Huan Yu - One of the best experts on this subject based on the ideXlab platform.
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Density and solidification feeding model of vacuum Counter-Pressure cast aluminum alloy under grade-pressuring conditions
China Foundry, 2016Co-Authors: Huan Yu, Bo Wen Xiong, Gang Lu, Suai XuAbstract:The density of vacuum Counter-Pressure cast aluminum alloy samples under grade-pressuring condition was studied. The effect of grade Pressure difference and time on the density of aluminum alloys was discussed, and the solidification feeding model under grade-pressuring condition was established. The results indicate the grade-Pressured solidification feeding ability of vacuum Counter-Pressure casting mainly depends on grade Pressure difference and time. With the increase of grade Pressure difference, the density of all the aluminum alloy samples increases, and the trend of change in density from the pouring gate to the top location is first decreasing gradually and then increasing. In addition, in obtaining the maximum density, the optimal grade-pressuring time is different for samples with different wall thicknesses, and the solidification time when the solid volume fraction of aluminum alloy reaches about 0.65 appears to be the optimal beginning time for grade-pressuring.
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microstructures and mechanical properties of vacuum Counter Pressure casting a357 alloys solidified under grade pressurising effects of melt temperature
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2014Co-Authors: Bo Wen Xiong, Zhenjun Wang, Huan YuAbstract:Abstract The effects of the melt temperature on the relative densities, microstructures and mechanical properties of vacuum Counter-Pressure casting A357 alloys solidified under grade-pressurising (200 kPa) were investigated. The results indicated that the relative densities and mechanical properties of samples solidified under grade-pressurising were affected by the melt temperature (580–610 °C). The optimal relative density and mechanical properties were achieved at a melt temperature of 590 °C. The microstructures varied with the melt temperature as a result of the differences in the strengths of the feeding flow and dendrites. The powerful feeding flow caused by grade-pressurising solidification can induce stress on the dendrites, resulting in the collapse of the primary dendrite network to form equiaxed dendrites. Decreasing the feeding Pressure proportionally to the solid volume fraction was proposed to obtain a suitable melt temperature for improving the density and refining the microstructure.
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Study on the Grade-Controlled Filling of Vacuum Counter-Pressure Casting Thin Wall Aluminum Alloy
Advanced Materials Research, 2011Co-Authors: Huan Yu, Bo Wen Xiong, Jia Hui Wang, Zhi Feng XuAbstract:The grade-controlled filling behavior of vacuum Counter-Pressure casting thin wall aluminum alloy was studied by numerical simulation and experimental investigation. According to the analysis of filling behavior under fixed Pressure and the casting structure, the technology of the grade-controlled filling of vacuum Counter-Pressure casting thin wall aluminum alloy was suggested. The result shows that the filling velocity was controlled on grade, resulting in the smoothly and sequential filling behavior, and the decreasing of defects in castings.
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Effect of Pressurizing Process on Molten Aluminum Alloy and Furnace Chamber Temperature of Vacuum Counter- Pressure Casting
Key Engineering Materials, 2011Co-Authors: Huan Yu, Bo Wen Xiong, Gang LuAbstract:In pressurizing process of vacuum Counter-Pressure casting, the pressurizing Pressure and velocity are very important parameters. Through testing the change of molten aluminum alloy and furnace chamber temperature with the time at difference pressurizing Pressure and velocity, the effect of pressurizing process on molten aluminum alloy and furnace chamber temperature of vacuum Counter- Pressure casting is studied. The results indicate the furnace chamber temperature reduces abruptly at beginning of pressurizing process, subsequently, it elevates to the initial temperature. Moreover, the change of the furnace chamber temperature is finished in the short time. But the change of molten aluminum alloy temperature is not obvious in pressurizing process. At identical pressurizing velocity, the change of the furnace chamber temperature is bigger with increase of pressurizing Pressure. Similarly, at identical pressurizing Pressure, the change of the furnace chamber temperature is bigger with increase of pressurizing velocity too. Moreover, the effect of pressurizing velocity on the furnace chamber temperature is bigger than pressurizing Pressure, and the change of the furnace chamber temperature don’t have effect on the change of molten aluminum alloy temperature.
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Study on Pressurizing Velocity and Model of Vacuum Counter-Pressure Filling Process
Advanced Materials Research, 2010Co-Authors: Huan Yu, Zhi Feng Xu, Bo Wen XiongAbstract:During filling process of vacuum Counter-Pressure casting, the pressurizing velocity is one of the most important parameters, and it affects whole filling process of molten metal and the quality of castings, the pressurizing velocity must be reasonably controlled and chosen. Through analyzing the pressurizing velocity of vacuum Counter-Pressure casting filling process, the results show that pressurizing velocity is related with absolute temperature of down kettle gas, radius of rising tube, initial volume of down kettle, height from original position of molten metal to top of rising tube and gas flux. When other conditions are same during filling process of vacuum Counter-Pressure casting, pressurizing velocity is proportional to gas flux, and it is linear. Meanwhile, through experimental verification for relationship of pressurizing velocity with gas flux, their actual relationships and mathematical models are obtained, and correction coefficient is determined at the range from 0.95 to 0.98.
Zhi Feng Xu - One of the best experts on this subject based on the ideXlab platform.
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Study on the Grade-Controlled Filling of Vacuum Counter-Pressure Casting Thin Wall Aluminum Alloy
Advanced Materials Research, 2011Co-Authors: Huan Yu, Bo Wen Xiong, Jia Hui Wang, Zhi Feng XuAbstract:The grade-controlled filling behavior of vacuum Counter-Pressure casting thin wall aluminum alloy was studied by numerical simulation and experimental investigation. According to the analysis of filling behavior under fixed Pressure and the casting structure, the technology of the grade-controlled filling of vacuum Counter-Pressure casting thin wall aluminum alloy was suggested. The result shows that the filling velocity was controlled on grade, resulting in the smoothly and sequential filling behavior, and the decreasing of defects in castings.
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Study on Pressurizing Velocity and Model of Vacuum Counter-Pressure Filling Process
Advanced Materials Research, 2010Co-Authors: Huan Yu, Zhi Feng Xu, Bo Wen XiongAbstract:During filling process of vacuum Counter-Pressure casting, the pressurizing velocity is one of the most important parameters, and it affects whole filling process of molten metal and the quality of castings, the pressurizing velocity must be reasonably controlled and chosen. Through analyzing the pressurizing velocity of vacuum Counter-Pressure casting filling process, the results show that pressurizing velocity is related with absolute temperature of down kettle gas, radius of rising tube, initial volume of down kettle, height from original position of molten metal to top of rising tube and gas flux. When other conditions are same during filling process of vacuum Counter-Pressure casting, pressurizing velocity is proportional to gas flux, and it is linear. Meanwhile, through experimental verification for relationship of pressurizing velocity with gas flux, their actual relationships and mathematical models are obtained, and correction coefficient is determined at the range from 0.95 to 0.98.
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Effects of Gating System on the Flow Behaviors during Vacuum Counter Pressure Casting Thin Wall Aluminum Alloy
Advanced Materials Research, 2010Co-Authors: Huan Yu, Bo Wen Xiong, Zhi Feng XuAbstract:The flow behaviors of molten Al alloy in sand mould cavity with varied gating system were simulated under vacuum Counter-Pressure casting and the ingate velocity was predicted using a software package. At same process conditions, the flow behaviors were investigated using electrode contact method. The comparison between the simulated results and the investigated results shows that a good agreement is achieved. The ingate flow velocity exceeding critical velocity and large velocity deviation are detected during filling mould withⅠtypes gating system, resulting in turbulent flow behavior. Whereas, flow behaviors take on stable flow pattern during filling the other mould cavity, although some differences of flow behaviors are present. The small ingate flow velocity and velocity deviation during filling mould cavity with Ⅲ type gating system may be conduce the more stable flow pattern thanⅡtype gating system.
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effect of holding Pressure on the microstructure of vacuum Counter Pressure casting aluminum alloy
Journal of Alloys and Compounds, 2010Co-Authors: Huan Yu, Zhi Feng Xu, Bo Wen XiongAbstract:The effect of holding Pressure on the microstructure of vacuum Counter-Pressure casting aluminum alloy was analyzed by observing the changes of the Si phase size and alloy density. The results show that with the increasing of holding Pressure of vacuum Counter-Pressure casting, the extrusion and infiltration ability among dendrites is enhanced and the microstructure of prepared alloy samples at the same location becomes finer, more uniform and denser. Under the same holding Pressure, the smallest extrusion and infiltration ability takes place at the middle of sample. Accordingly, from the pouring gate to middle, the microstructure of vacuum Counter-Pressure casting aluminum alloy sample becomes coarser, more non-uniform and less dense, while the microstructure from the middle to top becomes finer, more uniform and denser.
Hiroyuki Amino - One of the best experts on this subject based on the ideXlab platform.
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various applications of hydraulic Counter Pressure deep drawing
Journal of Materials Processing Technology, 1997Co-Authors: Takeo Nakagawa, K Nakamura, Hiroyuki AminoAbstract:Abstract Hydraulic Counter-Pressure deep drawing present numerous merits, many of which are not understood properly. In addition to clearing most forming restrictions, it is also capable of forming tapering shapes and complicated shapes. Economical advantages such as reduction of sheet metal material costs and die costs should also not be forgotten. This report summarizes the features of hydraulic Counter-Pressure deep drawing by introducing several actual examples of applications.
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Counter Pressure deep drawing and its application in the forming of automobile parts
Journal of Materials Processing Technology, 1990Co-Authors: Hiroyuki Amino, Kazuhiko Nakamura, Takeo NakagawaAbstract:Abstract Sheet metal forming with hydraulic Counter-Pressure has several advantages compared with conventional drawing, such as higher forming limits, higher accuracy of formed parts and the achievement of complicated formed shapes. About 50 special press machines have already been used in Japan for manufacturing lighting reflectors, aircraft parts and automobile parts. This report describes the techniques and the equipment used in the application of the process.
Takeo Nakagawa - One of the best experts on this subject based on the ideXlab platform.
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various applications of hydraulic Counter Pressure deep drawing
Journal of Materials Processing Technology, 1997Co-Authors: Takeo Nakagawa, K Nakamura, Hiroyuki AminoAbstract:Abstract Hydraulic Counter-Pressure deep drawing present numerous merits, many of which are not understood properly. In addition to clearing most forming restrictions, it is also capable of forming tapering shapes and complicated shapes. Economical advantages such as reduction of sheet metal material costs and die costs should also not be forgotten. This report summarizes the features of hydraulic Counter-Pressure deep drawing by introducing several actual examples of applications.
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Counter Pressure deep drawing and its application in the forming of automobile parts
Journal of Materials Processing Technology, 1990Co-Authors: Hiroyuki Amino, Kazuhiko Nakamura, Takeo NakagawaAbstract:Abstract Sheet metal forming with hydraulic Counter-Pressure has several advantages compared with conventional drawing, such as higher forming limits, higher accuracy of formed parts and the achievement of complicated formed shapes. About 50 special press machines have already been used in Japan for manufacturing lighting reflectors, aircraft parts and automobile parts. This report describes the techniques and the equipment used in the application of the process.
