Study On Ultrasonic Bonding Technology Of Carbon Fiber Reinforced Aluminum Matrix Composites

Carbon fiber reinforced aluminum matrix composites are mainly composed of aluminum alloy matrix and carbon fiber reinforcement,which can give full play to their respective performance characteristics and form a high strength and high modulus composite.The composite material not only has the characteristics of high thermal conductivity of aluminum and high tensile strength of carbon fiber,but also has good electrical conductivity and corrosion resistance.Therefore,carbon fiber reinforced aluminum matrix composites have broad application prospects in aviation,automobiles,ships,architecture and other fields.Due to the difference in structure and properties between the reinforcement and the aluminum matrix,the commonly used metal bonding methods are no longer suitable for the composite.Therefore,it is of great practical significance to study the ultrasonic bonding of carbon fiber reinforced aluminum matrix composites.In this paper,the ultrasonic bonding experiment of carbon fiber reinforced aluminum matrix composites was carried out by using the self-developed ultrasonic metal bonding equipment.The main research contents are as follows:(1)The ultrasonic metal consolidation system and auxiliary working system in the ultrasonic metal consolidation equipment were selected and designed,and then their feasibility was verified.Finally,the ultrasonic metal rolling consolidation equipment with integrated design of transducer and horn is developed.(2)After the ultrasonic metal consolidation test was carried out with self-made equipment,the micro-structure of the consolidation interface was observed by metallographic microscope,and there were four kinds of consolidation interface defects,namely,excessive deformation of the bonding line,chain-shaped,arcuate cavity and interface edge defects,and the causes of the consolidation interface defects were studied and analyzed.The effects of different consolidation process parameters(consolidation pressure,consolidation amplitude and consolidation speed)on the micro-bonding interface are studied and analyzed.It was concluded that consolidation pressure was the prerequisite for consolidation connection,consolidation amplitude changes the consolidation quality by influencing the deformation degree of the bonding line,and finally appropriate consolidation can further improve the consolidation quality.(3)Using thermocouple thermometer to collect the peak temperature of the consolidation area under different consolidation modes,so as to analyze the temperature rise of different consolidation modes;The distribution of temperature field and stress field under rolling consolidation was analyzed by simulation software,and it was found that the highest temperature was 172.249℃ and the deepest heat source center can reach 0.6 mm.(4)The mechanism of ultrasonic metal consolidation was analyzed by means of SEM,EDS and XRD,and it was found that the mechanism of ultrasonic rolling metal consolidation was micromechanical locking.(5)The tensile strength test,three-point bending test,micro-hardness test and surface roughness test were carried out on the consolidated specimens,and the test results were compared and analyzed,so as to analyze the influence of different process parameters on many mechanical properties of the consolidated specimens.