纤维金属层板(Fiber Metal Laminates,FMLs)传统成形方法难以成形复杂曲面构件,限制了其在汽车行业的应用。为提高FMLs成形能力,提出了一种直接采用模具加热预堆叠层板的热态气胀成形方法。首先通过力学性能试验探究了热塑性FMLs中材料...纤维金属层板(Fiber Metal Laminates,FMLs)传统成形方法难以成形复杂曲面构件,限制了其在汽车行业的应用。为提高FMLs成形能力,提出了一种直接采用模具加热预堆叠层板的热态气胀成形方法。首先通过力学性能试验探究了热塑性FMLs中材料铺层参数对力学性能影响,随后结合试验和仿真探究了热态气胀成形方法制备FMLs曲率构件过程中工艺参数对成形效果的影响,研究显示纤维参数决定了FMLs损伤容限,PA6树脂基FMLs成形工艺温度窗口为230~250℃,成形所需最低压强为3 MPa。研究结果表明利用热态气胀成形方法可成功制备热塑性FMLs曲率构件,温度和压强是决定成形效果的关键因素。展开更多
GdF3 was synthesized with Gd2O3 and NH4HF2 under atmospheric pressure and vacuum. The effects of pressure,temperature,and reactant ratio on the reaction process were investigated. A new mechanism for the synthesis of ...GdF3 was synthesized with Gd2O3 and NH4HF2 under atmospheric pressure and vacuum. The effects of pressure,temperature,and reactant ratio on the reaction process were investigated. A new mechanism for the synthesis of GdF3 was proposed. Powdered Gd2O3 started to react with NH4HF2 at low temperature,and the products were GdNH4F4,NH4F,NH3,and H2O. GdNH4F4 decomposed to GdF3 and NH4F after further high-temperature treatment,accompanying the volatilization and decomposition of NH4F. The whole process could be divided into three steps： synthesis,decomposition,and deamination. The initial and final reaction temperatures decreased under vacuum condition. An optimized process for the preparation of GdF3 was obtained： synthesis under atmospheric pressure at low temperature and decomposition and deamination under vacuum at high temperature.展开更多
文摘纤维金属层板(Fiber Metal Laminates,FMLs)传统成形方法难以成形复杂曲面构件,限制了其在汽车行业的应用。为提高FMLs成形能力,提出了一种直接采用模具加热预堆叠层板的热态气胀成形方法。首先通过力学性能试验探究了热塑性FMLs中材料铺层参数对力学性能影响,随后结合试验和仿真探究了热态气胀成形方法制备FMLs曲率构件过程中工艺参数对成形效果的影响,研究显示纤维参数决定了FMLs损伤容限,PA6树脂基FMLs成形工艺温度窗口为230~250℃,成形所需最低压强为3 MPa。研究结果表明利用热态气胀成形方法可成功制备热塑性FMLs曲率构件,温度和压强是决定成形效果的关键因素。
文摘GdF3 was synthesized with Gd2O3 and NH4HF2 under atmospheric pressure and vacuum. The effects of pressure,temperature,and reactant ratio on the reaction process were investigated. A new mechanism for the synthesis of GdF3 was proposed. Powdered Gd2O3 started to react with NH4HF2 at low temperature,and the products were GdNH4F4,NH4F,NH3,and H2O. GdNH4F4 decomposed to GdF3 and NH4F after further high-temperature treatment,accompanying the volatilization and decomposition of NH4F. The whole process could be divided into three steps： synthesis,decomposition,and deamination. The initial and final reaction temperatures decreased under vacuum condition. An optimized process for the preparation of GdF3 was obtained： synthesis under atmospheric pressure at low temperature and decomposition and deamination under vacuum at high temperature.
