Ti/Al₃Ti Laminated Composites Prepared By Ultrasonic Consolidation And Mechanical Properties Evaluated

Ti/Al3Ti laminated composite has many advantages such as low density,high specific strength,high specific stiffness,high temperature oxidation resistance,corrosion resistance and damage resistance.It has wide application prospects in aerospace and armor protection.However,the traditional method of preparing Ti/Al3Ti laminated composites is characterized by high cost,low reaction efficiency and poor quality of the composite materials.Therefore,it is necessary to develop a low cost,high quality,high efficiency and environmental friendly Ti/Al3Ti laminar composite material.In this paper,Ti/Al3Ti laminated composites were prepared by combination of ultrasonic consolidation and vacuum sintering.The consolidation quality between Ti/Al layers was detected by peeling test and microstructure observation,and the parameters of ultrasonic consolidation were optimized.Ti/Al3Ti layered composite was successfully prepared by in-situ reaction.The mechanical properties of the material were tested and the microstructure was analyzed,and the process parameters of the in-situ reaction were optimized.The mechanical properties of the Ti/Al3Ti laminated composites were tested,and the comprehensive properties of the composites were evaluated.The process of ultrasonic consolidation is studied.The effect of ultrasonic consolidation parameters on the consolidation quality of Ti/Al laminated composites is explored,and the mechanism of ultrasonic consolidation is expounded.It is found that the greater the ultrasonic amplitude is,the better the experimental consolidation effect is.By means of SEM+EDS,microscopic observation and element content distribution of the debonding samples under ultrasonic consolidation parameters were carried out to confirm the form and effect of interface bonding.Then the mechanical properties of the Ti/Al composites were tested,the mechanical properties of the laminated composites were evaluated,and the form of crack propagation was studied.Finally,the ultrasonic consolidation process parameters are optimized.The ultrasonic amplitude is 35 m,the normal pressure is 1.5KN,the consolidation temperature is 200 ?,and the consolidation speed is 34.5mm/s.Ti/Al3Ti laminated composites were prepared by in-situ reaction test using Ti/Al laminated composites as raw materials.After analyzing the phase composition of the Ti/Al3Ti laminated composite,the intermetallic compound Al3Ti is the only product,and the relationship between the thickness of the reaction layer and the time is studied.The relationship between the thickness of the reaction layer and the time can be expressed as y=2.306t^1.13 83(in which Y represents the thickness of the reverse layer,and the T is expressed as the time).The experimental results show that when Al is completely reacted,the volume fraction of Al3Ti reaches the maximum,resulting in a hole in the Al3Ti layer,which greatly reduces the mechanical properties of the material.Based on the above study,the in-situ reaction test scheme was optimized,and the high quality Ti/Al3Ti laminated composite was successfully prepared,with a compact structure,good interface bonding and no defect.The process scheme was optimized.The mechanical properties of Ti/Al3Ti laminated composites were tested by compression test,in-situ bending test and uniaxial dynamic compression test.The reasons for the increase of ductility and plasticity of materials are analyzed,and the relationship between energy absorption characteristics and crack propagation is explained.It is found that the Ti layer and interlayer interface in the Ti/Al3Ti laminated composites can effectively prevent the crack propagation and change the crack propagation direction.This will greatly enhance the plasticity,toughness and energy absorption characteristics of the material.