Research On Mechanical Properties Of Interlayer Hybrid Fiber Composite Materials For Wind Power I-beam

Facing the dual problems of energy scarcity and environmental degradation,countries around the world have adjusted their national development strategies and paid more attention to the development and utilization of wind energy instead of traditional energy.With the development of offshore wind power and low speed of wind power technology,the use of pure glass fiber as a reinforcement material has been unable to meet the basic stiffness requirements of large-scale wind power installation technology,and pure carbon fiber composite materials are expensive and the overall performance is not ideal.Effectively mixing carbon fiber and glass fiber can not only make up for the brittleness and impact resistance of carbon fiber,improve the modulus and rigidity of glass fiber,but also solve the high cost problem caused by the high amount of carbon fiber.Therefore,the glass carbon hybrid structure design scheme provides a good solution and optimization scheme for the increase of the length of the I-beam of the wind power blade.The specific content,conclusions and results of this study are as follows:(1)Characterize the curing characteristics of the 2511-1A/BS epoxy resin matrix by differential scanning calorimeter,considering the curing effect and efficiency,the curing process of the resin system is set to 85℃/150 min + 130℃/50 min.A rotary rheometer was used to analyze the viscous flow characteristics of the resin at constant temperature and variable temperature.Considering the injection efficiency and fiber infiltration effect,40 ℃ was determined as the optimal temperature point for resin defoaming and infusion during the VARI molding process.(2)Based on Darcy’s law,the unidirectional method is used to study the effect of interlayer mixing on the permeability of glassy carbon fabric.The results show that with the increase of carbon fiber content,the flow front of epoxy resin gradually changes from a sharp peak shape to a gentle peak shape,and at the same time,the injection time increases.Under a certain mixing ratio,the square of the flow front position of epoxy resin shows a linear relationship with time;whilethe fabric permeability shows a linear growth trend with the increase of carbon content.(3)Longitudinal and lateral stretching and compression of different glass-carbon hybrid ratio plates,the research shows that the longitudinal stretching and compression properties are significantly improved with the increase of carbon fiber content;and the lateral performance mainly depends on the degree of resin/fiber bonding and bundling Yarn,the increase is more obvious;however,the transverse tensile modulus shows a negative mixing effect,which decreases with the increase of carbon content;while the transverse compression performance shows up and down fluctuations with the mixing ratio,and there is no significant change.(4)Three-point bending and interlaminar shearing of plates with different glass-carbon hybrid ratios.Studies have shown that bending strength changes irregularly with increasing carbon content.For pure GFRP plates,the bending modulus is obtained with increasing carbon content Significant improvement.The failures of the bent samples are all compression-side fractures,and the cross-section fractures of pure glass and pure carbon composites are relatively neat,while hybrid composites mostly exhibit interlayer fractures or dendritic crack enrichment.In terms of HFRP interlayer shear performance,the shear strength increases with the increase of carbon content,and the shear modulus increases first and then decreases with the increase of carbon content.The failure of shear specimens is mainly layered failure,accompanied by partial matrix and fiber crack failure.Appropriately increasing the carbon fiber content can reduce the phenomenon of large-area delamination fracture area of the fiber.When the mixing ratio is 1: 4and 1:3,the plate shows fiber enrichment and fracture,but no large-area delamination cracking phenomenon occurs,and the sample damages the morphology Relatively complete.(5)Using ANSYS modeling to simulate and analyze the static modulus of hybrid laminates.By applying cantilever beam constraints and simply supported beam constraints,the modulus of fiber-reinforced composites with various hybrid ratios is calculated.The results show that with the increase of carbon fiber content,the tensile,bending,and compression modulus growth trends,the simulation results are basically consistent with the experimental results.