Influence of Welding Surface Distance on Welding Head
The propagation of ultrasonic waves in plastic media is dominated by longitudinal waves, and the maximum longitudinal wave peaks often appear at half wavelength. When the distance is close to half wavelength, the transmission of ultrasonic waves to the welding interface heat energy is the largest, and good ultrasonic welding joints can be obtained.
Ultrasonic welding of different thicknesses of HS 1000 (aryl phosphate and clay-modified polyphenylene ether, half-wavelength 3.86 cm). The results show that the critical thickness is 3.86 cm. When the critical thickness is less than the critical thickness, the strength and elongation of the ultrasonic welded joint increase with the thickness, and when the thickness is greater than the critical thickness, the strength and elongation of the joint decrease rapidly.
The welding effect of ultrasonic welding machine is proportional to elastic modulus, friction coefficient and thermal conductivity, and inversely proportional to density, specific heat capacity and melting point.
The influence of ultrasonic welding is mainly related to the melting point and surface friction coefficient of the material. These parameters vary with different materials and temperatures. The changes of these parameters during ultrasonic welding will affect the temperature, stress and deformation of the ultrasonic welding zone, thereby affecting the quality of ultrasonic welding.