Study on Disassembling Approaches of Electronic Components Mounted on PCBs

With the rapid development of modern industry, more and more electronic and electric products containing Printed Circuit Boards (PCBs) are produced, consumed, and discarded in our daily life. The disassembling and reuse of electronic components mounted on these discarded PCBs are meaningful to reuse the valuable electronic components, reduce the pollution to the environment, reuse the bare PCBs, and retrieve the materials of PCBs. Four evaluation principles of disassembling methods, components reutilization rate, reliability and uniformity, thermal energy consumption and environmental impact, are analyzed. Based on the analysis of the existing disassembling approach, a new method is presented, which adopts a kind of special liquor, methylphenyl silicone oil, as the medium to transmit heat to the PCBs. The ultrasonic is used in the liquor to accelerate the melting and dropping of soldering tin through ultrasonic vibrations. An experimental framework has been established. The experiment proves that the method has good performances such as high efficiency of energy utilization and high unsoldering proportion.