This study presents the first stage of a multi-scale numerical framework designed to predict the non-linear constitutive behavior of metal-composite interfaces in titanium-graphite fiber metal laminates. Scanning elec...This study presents the first stage of a multi-scale numerical framework designed to predict the non-linear constitutive behavior of metal-composite interfaces in titanium-graphite fiber metal laminates. Scanning electron microscopy and x-ray diffraction techniques are used to characterize the baseline physical and chemical state of the interface. The physics of adhesion between the metal and polymer matrix composite components are then evaluated on the atomistic scale using molecular dynamics simulations. Interfacial mechanical properties are subsequently derived from these simulations using classical mechanics and thermodynamics. These molecular-level property predictions are used in a companion study to parameterize a continuum-level finite element model of the interface by means of a traction-separation constitutive law. Extension of the proposed approach to other dissimilar metal- or metal oxide-polymer interfaces is also discussed.展开更多
Through theoretical analysis and finite element simulation,the low-velocity impact of rectangular foam-filled fiber metal laminate(FML)tubes is studied in this paper.According to the rigid-plastic material approximati...Through theoretical analysis and finite element simulation,the low-velocity impact of rectangular foam-filled fiber metal laminate(FML)tubes is studied in this paper.According to the rigid-plastic material approximation with modifications,simple analytical solutions are obtained for the dynamic response of rectangular foam-filled FML tubes.The numerical calculations for low-velocity impact of rectangular foam-filled FML tubes are conducted.The accuracy of analytical solutions and numerical results is verified by each other.Finally,the effects of the metal volume fraction of FMLs,the number of the metal layers in FMLs,and the foam strength on the dynamic response of foam-filled tubes are discussed through the analytical model in details.It is shown that the force increases with the increase in the metal volume fraction in FMLs,the number of the metal layers in FML,and the foam strength for the given deflection.展开更多
GLARE(glass fibre/epoxy reinforced aluminum laminate) is a member of the fiber metal laminate(FML) family,and is built up of alternating metal and fiber layers.About 500 m 2 GLARE is employed in each Airbus A380 becau...GLARE(glass fibre/epoxy reinforced aluminum laminate) is a member of the fiber metal laminate(FML) family,and is built up of alternating metal and fiber layers.About 500 m 2 GLARE is employed in each Airbus A380 because of the superior mechanical properties over the monolithic aluminum alloys,such as weight reduction,improved damage tolerance and higher ultimate tensile strength.Many tons of new GLARE scraps have been accumulated during the Airbus A380 manufacturing.Moreover,with the increasing plane orders of Airbus A380,more and more end-of-life(EOL) GLARE scrap will be generated after retire of planes within forty years.Thermal processing is a potential method for the material recycling and re-use from GLARE with the aim of environmental protection and economic benefits.The current study indicatdes that thermal delamination is a crucial pre-treatment step for the GLARE recycling.The decomposition behavior of the epoxy resins at elevated temperatures was investigated by using the simultaneous thermal analysis,thermogravimetry analysis(TGA) and differential scanning calorimetry(DSC).Based on the thermal analysis results,GLARE thermal delamination experiments at refined temperatures were carried out to optimize the treatment temperature and holding time.展开更多
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
It is known that fiber metal laminates （FML） as one of hybrid materials with thin metal sheets and fiber/epoxy layers have the characteristics of the excellent damage tolerance, fatigue and impact properties with a ...It is known that fiber metal laminates （FML） as one of hybrid materials with thin metal sheets and fiber/epoxy layers have the characteristics of the excellent damage tolerance, fatigue and impact properties with a relatively low density. Therefore, the mechanical components using FML can contribute the enhanced safety level of the sound construction toward the whole body. In this study, the impact performance of carbon reinforced aluminum laminates （CARAL） is investigated by experiments and numerical simulations. Drop weight tests are carried out with the weight of 4.7 kg at the speed of 1 and 2 m/s, respectively. Dynamic non-linear transient analyses are also accomplished using a finite element analysis software, ABAQUS. The experiment results and numerical results are compared with impact load-time histories. Also, energy-time histories are applied to investigate the impact performance of CARAL.展开更多
研究了AZ31B镁合金经高锰酸盐-磷酸盐改性处理后的表面形貌、润湿性及镁合金-玻璃纤维/环氧树脂叠层板的界面粘接性能和力学性能。结果表明,AZ31B镁合金表面经高锰酸盐-磷酸盐改性处理5min后形成的转化膜为致密的网状单层膜,此时镁合金...研究了AZ31B镁合金经高锰酸盐-磷酸盐改性处理后的表面形貌、润湿性及镁合金-玻璃纤维/环氧树脂叠层板的界面粘接性能和力学性能。结果表明,AZ31B镁合金表面经高锰酸盐-磷酸盐改性处理5min后形成的转化膜为致密的网状单层膜,此时镁合金的面自由能达到最大值,值为92.04 m J/m2,比仅打磨处理的镁合金提高了64.6%左右,镁合金的表面润湿性得到极大的改善。与仅打磨处理的镁合金制备的镁合金-玻璃纤维/环氧树脂叠层板相比,镁合金经高锰酸盐-磷酸盐改性处理后制备的叠层板的结合界面更为致密、均匀。仅打磨处理的叠层板和高锰酸盐-磷酸盐改性处理的叠层板的抗拉强度分别为284.2 MPa和298.3 MPa,分别比AZ31B镁合金板提高了23%和29.1%。展开更多
文摘This study presents the first stage of a multi-scale numerical framework designed to predict the non-linear constitutive behavior of metal-composite interfaces in titanium-graphite fiber metal laminates. Scanning electron microscopy and x-ray diffraction techniques are used to characterize the baseline physical and chemical state of the interface. The physics of adhesion between the metal and polymer matrix composite components are then evaluated on the atomistic scale using molecular dynamics simulations. Interfacial mechanical properties are subsequently derived from these simulations using classical mechanics and thermodynamics. These molecular-level property predictions are used in a companion study to parameterize a continuum-level finite element model of the interface by means of a traction-separation constitutive law. Extension of the proposed approach to other dissimilar metal- or metal oxide-polymer interfaces is also discussed.
基金the National Natural Science Foundation of China(Nos.11872291 and11972281)the Jiangsu Key Laboratory of Engineering Mechanics,Southeast University+2 种基金the Fundamental Research Funds for the Central Universities(No.LEM21B01)the Key Laboratory of Impact and Safety Engineering(Ningbo University),Ministry of Education(No.cj202002)the Natural Science Basic Research Plan in Shaanxi Province of China(No.2020JM-034)。
文摘Through theoretical analysis and finite element simulation,the low-velocity impact of rectangular foam-filled fiber metal laminate(FML)tubes is studied in this paper.According to the rigid-plastic material approximation with modifications,simple analytical solutions are obtained for the dynamic response of rectangular foam-filled FML tubes.The numerical calculations for low-velocity impact of rectangular foam-filled FML tubes are conducted.The accuracy of analytical solutions and numerical results is verified by each other.Finally,the effects of the metal volume fraction of FMLs,the number of the metal layers in FMLs,and the foam strength on the dynamic response of foam-filled tubes are discussed through the analytical model in details.It is shown that the force increases with the increase in the metal volume fraction in FMLs,the number of the metal layers in FML,and the foam strength for the given deflection.
基金the Royal Netherlands Academy of Science and Arts(KNAW)(No.10CDP026)the National Outstanding Young Scientist Foundation of China (No.50825401)the National Natural Science Foundation of China(No.50821003)
文摘GLARE(glass fibre/epoxy reinforced aluminum laminate) is a member of the fiber metal laminate(FML) family,and is built up of alternating metal and fiber layers.About 500 m 2 GLARE is employed in each Airbus A380 because of the superior mechanical properties over the monolithic aluminum alloys,such as weight reduction,improved damage tolerance and higher ultimate tensile strength.Many tons of new GLARE scraps have been accumulated during the Airbus A380 manufacturing.Moreover,with the increasing plane orders of Airbus A380,more and more end-of-life(EOL) GLARE scrap will be generated after retire of planes within forty years.Thermal processing is a potential method for the material recycling and re-use from GLARE with the aim of environmental protection and economic benefits.The current study indicatdes that thermal delamination is a crucial pre-treatment step for the GLARE recycling.The decomposition behavior of the epoxy resins at elevated temperatures was investigated by using the simultaneous thermal analysis,thermogravimetry analysis(TGA) and differential scanning calorimetry(DSC).Based on the thermal analysis results,GLARE thermal delamination experiments at refined temperatures were carried out to optimize the treatment temperature and holding time.
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。
基金supported by a grant-in-aid for the Na-tional Core Research Center Program from the Ministry of Education Science & Technology and the Korea Science & Engineering Foundation (No. R15-2006-022-01001-0)support by the Korea Science and Engineering Foundation (KOSEF) NRL Program grant funded by the Korea government (MEST) (No. R0A-2008-000-20017-0)
文摘It is known that fiber metal laminates （FML） as one of hybrid materials with thin metal sheets and fiber/epoxy layers have the characteristics of the excellent damage tolerance, fatigue and impact properties with a relatively low density. Therefore, the mechanical components using FML can contribute the enhanced safety level of the sound construction toward the whole body. In this study, the impact performance of carbon reinforced aluminum laminates （CARAL） is investigated by experiments and numerical simulations. Drop weight tests are carried out with the weight of 4.7 kg at the speed of 1 and 2 m/s, respectively. Dynamic non-linear transient analyses are also accomplished using a finite element analysis software, ABAQUS. The experiment results and numerical results are compared with impact load-time histories. Also, energy-time histories are applied to investigate the impact performance of CARAL.
文摘研究了AZ31B镁合金经高锰酸盐-磷酸盐改性处理后的表面形貌、润湿性及镁合金-玻璃纤维/环氧树脂叠层板的界面粘接性能和力学性能。结果表明,AZ31B镁合金表面经高锰酸盐-磷酸盐改性处理5min后形成的转化膜为致密的网状单层膜,此时镁合金的面自由能达到最大值,值为92.04 m J/m2,比仅打磨处理的镁合金提高了64.6%左右,镁合金的表面润湿性得到极大的改善。与仅打磨处理的镁合金制备的镁合金-玻璃纤维/环氧树脂叠层板相比,镁合金经高锰酸盐-磷酸盐改性处理后制备的叠层板的结合界面更为致密、均匀。仅打磨处理的叠层板和高锰酸盐-磷酸盐改性处理的叠层板的抗拉强度分别为284.2 MPa和298.3 MPa,分别比AZ31B镁合金板提高了23%和29.1%。
