Natural Vibration Characteristics And Vibration Response Analysis Of Glass/Carbon Fiber Hybrid Composite Laminates

Hybrid composite materials have been widely used in many industrial fields such as aerospace,wind turbine blades,automobiles,and infrastructure due to their high designability,high specific modulus,high specific stiffness,wear resistance,and corrosion resistance.By using carbon and glass fibers to jointly strengthen the same resin matrix,glass/carbon fiber hybrid composites(G/CFHC)with higher specific strength and stiffness can be obtained,which is a commonly used hybrid composite material.In the field of aviation industry,G/CFHC laminated structures are often used as the constituent materials of some key structures.Factors such as the ply design and ambient temperature of G/CFHC laminated structures can have an impact on the natural vibration characteristics and vibration response of the structure itself.Analyzing the impact of these factors on the natural vibration characteristics and vibration response of G/CFHC laminated structures has important reference significance for optimizing the vibration characteristics of G/CFHC laminated structures.Based on the first order shear deformation theory and finite element method,this paper investigates the effects of ply design and ambient temperature on the natural vibration characteristics of G/CFHC laminated plates;Based on CAE simulation analysis,the influence of pavement design on its vibration response is explored.The main contents and conclusions are as follows:(1)Based on the first order shear deformation theory and finite element method,the undamped natural vibration characteristics of G/CFHC laminates were analyzed,and the natural vibration characteristics of G/CFHC laminates with different fiber laying angles,hybrid ratios,ply thicknesses,and ply sequences were studied and compared.The results show that the first three natural frequencies of G/CFHC laminates decrease with the increase of fiber laying angle,and the influence of carbon fiber laying angle on their natural frequencies is more obvious than that of glass fiber laying angle;It will increase with the increase of the proportion of carbon fiber/epoxy resin composites;It will increase with the increase of the ply thickness,and increasing the thickness of the carbon fiber/epoxy resin composite single layer board will have a more significant impact on its size;The carbon fiber/epoxy resin composite material will be affected by the laying sequence.The closer it is to the outside during laying,the greater its value will be.The influence of laying angle and hybrid ratio on the vibration mode of G/CFHC laminated plates is obvious.(2)Based on the analysis of undamped natural vibration characteristics of G/CFHC laminates,the influence of variable temperature environment on their natural frequencies was analyzed.The results showed that the first three natural frequencies of G/CFHC laminates would decrease with the increase of ambient temperature.The higher the ambient temperature is,the more obvious the influence of the laying angle and the laying sequence on the first three natural frequencies of G/CFHC laminates will be;The smaller the impact of the hybrid ratio.(3)Harmonic response analysis,transient response analysis,and random vibration analysis were conducted on G/CFHC laminated plates with different fiber laying angles,hybrid ratios,and ply sequences to explore their vibration characteristics under load.The results showed that the greater the fiber laying angle,the greater the displacement response amplitude of the free end of the G/CFHC cantilever laminated plate at resonance,and the greater the displacement response amplitude under simple harmonic load,The maximum response value of energy under random load is also relatively larger.The larger the proportion of glass fiber/epoxy resin composites in G/CFHC laminates,the greater the amplitude of the free end of the G/CFHC cantilever laminates under resonance and harmonic loading,and the greater the maximum energy response value under random loading.An increase in the thickness of a single layer of G/CFHC cantilever laminate can reduce its amplitude at free end resonance,and in contrast,an increase in the thickness of a single layer of carbon fiber/epoxy resin composite has a more significant impact on the vibration amplitude of G/CFHC laminate.When the laying of carbon fiber/epoxy resin composite single layer plate is concentrated towards the outer side of the laminated plate,the amplitude of the free end of the G/CFHC cantilever laminated plate at resonance or under simple harmonic load is smaller,and the maximum energy response value under random load is also smaller.