A201铝合金为目前使用中机械强度最佳的铸造铝合金,但其铸造性能不良,铸造时常产生缺陷。通过系统地改变冒口大小及平板铸件的长度及厚度,探讨宽凝固范围铝合金的冒口理论,进而在铸造生产时,为冒口设计及金属凝固提供参考,是本研究的目...A201铝合金为目前使用中机械强度最佳的铸造铝合金,但其铸造性能不良,铸造时常产生缺陷。通过系统地改变冒口大小及平板铸件的长度及厚度,探讨宽凝固范围铝合金的冒口理论,进而在铸造生产时,为冒口设计及金属凝固提供参考,是本研究的目的。由实验结果显示,A201铝合金的冒口设计法则明显与常用的钢铁冒口设计法则(Caine法则)不同,经回归分析,冒口比(V R )与凝固比(F R )的关系式为:V R ≥0 52(F R )2 09。展开更多
The thermodynamic characterization as well as the rheological characterization of the A201 alloy were conducted.Thermodynamic simulations (CALPHAD method) and calorimetric experiments were performed to determine the s...The thermodynamic characterization as well as the rheological characterization of the A201 alloy were conducted.Thermodynamic simulations (CALPHAD method) and calorimetric experiments were performed to determine the solidus and liquidus temperatures, the melting range and the sensitivity of the solid fraction at the thixoforming temperatures.The rheology of aluminium alloy A201 was examined using a high temperature Searle rheometer.The flow behaviour was analyzed with concentric cylinders of graphite to avoid chemical interactions with the liquid or semi-solid aluminium.The rotational body was grooved to prevent a phenomenon called wall slippage.Continuous cooling experiment was used to observe the shear rate effects on the flow behaviour.It can be seen that the viscosity level decreases at higher shear rates.Shear rate jump experiment was carried out to evaluate the steady state flow curve within the analyzed shear rate range from 60 s-1 to 260 s-1.It is found that the power law indexes are-1.35 and-1.49 for 35% and 45% solid fraction, respectively.Finally, some mechanical property data of as-cast and as-thixoformed A201 alloy are included indicating the potential for high strength applications.展开更多
文摘A201铝合金为目前使用中机械强度最佳的铸造铝合金,但其铸造性能不良,铸造时常产生缺陷。通过系统地改变冒口大小及平板铸件的长度及厚度,探讨宽凝固范围铝合金的冒口理论,进而在铸造生产时,为冒口设计及金属凝固提供参考,是本研究的目的。由实验结果显示,A201铝合金的冒口设计法则明显与常用的钢铁冒口设计法则(Caine法则)不同,经回归分析,冒口比(V R )与凝固比(F R )的关系式为:V R ≥0 52(F R )2 09。
基金the "Ministerio de Ciencia e Innovación" and to the "Fondos FEDER",project "Integrauto" PSE-370000-2008-03the Basque Government,project "ETORTEK, Manufacturing 0.0 II",for their financial support
文摘The thermodynamic characterization as well as the rheological characterization of the A201 alloy were conducted.Thermodynamic simulations (CALPHAD method) and calorimetric experiments were performed to determine the solidus and liquidus temperatures, the melting range and the sensitivity of the solid fraction at the thixoforming temperatures.The rheology of aluminium alloy A201 was examined using a high temperature Searle rheometer.The flow behaviour was analyzed with concentric cylinders of graphite to avoid chemical interactions with the liquid or semi-solid aluminium.The rotational body was grooved to prevent a phenomenon called wall slippage.Continuous cooling experiment was used to observe the shear rate effects on the flow behaviour.It can be seen that the viscosity level decreases at higher shear rates.Shear rate jump experiment was carried out to evaluate the steady state flow curve within the analyzed shear rate range from 60 s-1 to 260 s-1.It is found that the power law indexes are-1.35 and-1.49 for 35% and 45% solid fraction, respectively.Finally, some mechanical property data of as-cast and as-thixoformed A201 alloy are included indicating the potential for high strength applications.
基金National Natural Science Foundation of China(51362017)Major Science and Technology Project of Yunnan Province-Major Project of New Materials(2018ZE005)。
