超声焊接的研究和工艺模型

为了能进行超声焊接工艺的线检测，必须了解超声焊接的机制。本文对这个问题作了研究。在本实验所用的焊机中，用一块压电晶体作为换能器产生超声振动。在通常的焊接过程中，研究了换能器驱动信号和从机械振动测出的信号这二者的变动情况，同时还研究了这二种信号的各次谐波信号。

Study on Process Model of Ultrasonic Bonding

To make an on-line monitoring of ultrasonic bonding process possible, an understanding of ultrasnoic bonding mechanism is essential. In bonding machine, a pieee of piezoeleetric crystal is used as a transducer to produce ultrasonic vibration. Variations of transducer-driving signal and the signal detected from mechanical vibration were studied during the normal bonding process, the harmonics of these two signals were concureently studied as well. It turns out that the 5th harmonic of the detected signal was susceptible to the mechanical vibration of bonding tool, and experiments were designed and conducted to clarify the behavior of this signal during the whole bonding process. According to the observed results, a bonding model was proposed which is based on the consideration of the flow of ultrasonic power. This model connects the harmonic signal waveform of a bonding operation with the physical phenomena of that process. Consequently, one can use this model to analyse this harmonic signal, get a insight of what was taken place in bonding zone and predict the bonding result, the strength of this bond.