Application of Concentrated Electromagnetic Energy Streams in Electronics Manufacturing

Aims: The concentrated streams ultrasonic (US) and high frequency (HF) energy are widely used in electronics manufacture in assembly and mounting process. US soldering is non-polluting and more economic process, as such operations as fluxing and clearing, demanding expenses of time and materials, are excluded. US soldering joining difficult soldering materials and nonmetallic materials: ceramics, glass, ferrite. HF electromagnetic energy possessing of local high speed heating of conducting materials in any environments provides formation of qualitative soldering connections in electronics products.

Methods: The US metallization of glass-ceramic materials was performed in the chamber with a residual rarefaction of 1–10 Pa and using IR heating. A low-melt Sn–10Zn solder and experimentally developed sol­der on the basis Sn with the addition of Zn and In were used. The cavitation pressure in the melted solders was evaluated according to the spectral density of the cavitation noise in the frequency band of 100–450 kHz using a cavitometer. The optimal frequency of US oscillating local soldering system is modelling with ANSYS. Two types of inductors are investigated: circular winding inductor and with open-ended magnetic circuit. The first contained HF generator, circular inductor with the cylindrical detail, and capacitor. In the second the generator was connected to winding coils on magnetic circuit of ferromagnetic material.

Results and Conclusion: At local input US fluctuations in melts concentrate US energy in small volume and lower oxidation of solder in a bath. US fluctuations parallel to soldering surface are preferable to increase of soldering connections durability, maintenance of high stability of processes and reduction of mechanical influence by products. The efficient management of power and speed of induction heating is necessary to control the size of current power and speed of the induction heating in working winds.