Out-of-autoclave(OoA) processing has the advantages of low cost,light weight and environmental protection,and has become a hot spot in the field of composite materials worldwide. This paper investigates the applicatio...Out-of-autoclave(OoA) processing has the advantages of low cost,light weight and environmental protection,and has become a hot spot in the field of composite materials worldwide. This paper investigates the application of OoA processing in the gondola of the AS700 civil manned airship. The production cost of gondolas is reduced by selecting low cost materials such as glass fiber,PVC foam and OoA processing. The porosity of parts is reduced and controlled at about 2% by optimizing the edge breathing of prepreg during curing. The maximum tensile strain of the glass fiber is 4 593 με;its maximum compressive strain is 3 680 με;and its maximum shear strain is4 884 με. The maximum Von Mises stress of the foam is 0.70 MPa. These settings all meet the margin requirement of safety. Finally,the ultimate load test of the gondola is carried out to verify the safety of the gondola structure. Our study presents critical parameters for the gondola design,including load,structure,strength,and manufacturing process test,and provides certain references for the design of similar products.展开更多
Effects of layer quantities and stacking sequences on L-shape composite manufacturing qualities in using OOA(out-of-autoclave)prepregs were studied.The mechanisms of air evacuated in 5 kinds of lay-ups were revealed b...Effects of layer quantities and stacking sequences on L-shape composite manufacturing qualities in using OOA(out-of-autoclave)prepregs were studied.The mechanisms of air evacuated in 5 kinds of lay-ups were revealed by image analysis of cut surfaces and thickness measurements.Results show that air in OOA prepregs is evacuated in two ways.Most of the air is forced out of layers directly by vacuum before air accesses in prepregs closed.Very little entrapped air moves perpendicularly to outer layers under hydrostatic resin pressure.When a laminate contains less than 16 layers,voids can hardly be found in layers.When a laminate contains more than 16 layers,voids cannot be expelled completely during the window of vertical movement.As for stacking sequences,the synergetic effect of slip function and nest function determines the thickness and voids content of laminates.Results show that the average of single layer thickness of unidirectional layers is the lowest,and the average of single layer thickness of quasi-isotropic layers is the highest.The voids content of quasi isotropic is the highest,which is consistent with the theoretical analysis.展开更多
为满足复合材料低成本制造需求,研发出了一款适用于非热压罐(out of autoclave, OOA)成型工艺的环氧树脂LCE201。采用热熔法制作预浸料,将预浸料分别用热压罐和OOA成型工艺制作层压板。比较了两种成型工艺制作层压板的物理和力学性能,...为满足复合材料低成本制造需求,研发出了一款适用于非热压罐(out of autoclave, OOA)成型工艺的环氧树脂LCE201。采用热熔法制作预浸料,将预浸料分别用热压罐和OOA成型工艺制作层压板。比较了两种成型工艺制作层压板的物理和力学性能,结果表明,两者性能相当。使用该预浸料采用OOA成型工艺制作某无人机U型后墙制件,制件厚度及无损结果满足指标要求。展开更多
基金supported in part by China Special Vehicle Research Institute and the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Out-of-autoclave(OoA) processing has the advantages of low cost,light weight and environmental protection,and has become a hot spot in the field of composite materials worldwide. This paper investigates the application of OoA processing in the gondola of the AS700 civil manned airship. The production cost of gondolas is reduced by selecting low cost materials such as glass fiber,PVC foam and OoA processing. The porosity of parts is reduced and controlled at about 2% by optimizing the edge breathing of prepreg during curing. The maximum tensile strain of the glass fiber is 4 593 με;its maximum compressive strain is 3 680 με;and its maximum shear strain is4 884 με. The maximum Von Mises stress of the foam is 0.70 MPa. These settings all meet the margin requirement of safety. Finally,the ultimate load test of the gondola is carried out to verify the safety of the gondola structure. Our study presents critical parameters for the gondola design,including load,structure,strength,and manufacturing process test,and provides certain references for the design of similar products.
文摘Effects of layer quantities and stacking sequences on L-shape composite manufacturing qualities in using OOA(out-of-autoclave)prepregs were studied.The mechanisms of air evacuated in 5 kinds of lay-ups were revealed by image analysis of cut surfaces and thickness measurements.Results show that air in OOA prepregs is evacuated in two ways.Most of the air is forced out of layers directly by vacuum before air accesses in prepregs closed.Very little entrapped air moves perpendicularly to outer layers under hydrostatic resin pressure.When a laminate contains less than 16 layers,voids can hardly be found in layers.When a laminate contains more than 16 layers,voids cannot be expelled completely during the window of vertical movement.As for stacking sequences,the synergetic effect of slip function and nest function determines the thickness and voids content of laminates.Results show that the average of single layer thickness of unidirectional layers is the lowest,and the average of single layer thickness of quasi-isotropic layers is the highest.The voids content of quasi isotropic is the highest,which is consistent with the theoretical analysis.
文摘为满足复合材料低成本制造需求,研发出了一款适用于非热压罐(out of autoclave, OOA)成型工艺的环氧树脂LCE201。采用热熔法制作预浸料,将预浸料分别用热压罐和OOA成型工艺制作层压板。比较了两种成型工艺制作层压板的物理和力学性能,结果表明,两者性能相当。使用该预浸料采用OOA成型工艺制作某无人机U型后墙制件,制件厚度及无损结果满足指标要求。
