超声输入能量对 C_f/Al 与 TC4 接头微观组织和性能的影响

Ultrasonic soldering was used to join carbon fiber reinforced aluminum matrix composites (C_f/Al) and TC4 alloy in this work. The effects of ultrasonic power on the microstructure and mechanical properties of the joints were studied. To reduce the soldering temperature, a TiAl₃ particles reinforced layer was generated on the surface of TC4 alloy by hot dipping. The filler was Zn5Al and the soldering temperature was 420℃. Results show that the thickness of TiAl₃ reinforced layer has a thickness of 80 μm when the holding time is 30 min. Ultrasonic power has a significant effect on the distribution of TiAl₃ particles and carbon fiber in the joint. When the ultrasonic power is 333.3 W, TiAl₃ and carbon fiber has a small amount in the joint due to the weak dissolution of the base material and small solder squeeze. With increasing the ultrasonic power, the amount of TiAl₃ and carbon fiber in the joint gradually increases. When the ultrasonic power is 1 000 W, the composite joint seam reinforced by TiAl₃ particles and carbon fiber is obtained when the ultrasonic time is 10 s. The results of nanoindentation test show that the nanoindentation hardness and modulus of TiAl₃ particles are 7.56 GPa and 181.73 GPa, which are higher than other areas of the joint. When the ultrasonic power is 1 000 W, the shear strength of the joint is 30.16 MPa, which is almost as strong as the C_f/Al base material.