Study of a new flux for lead-free solder paste

Active agent mixed with organic acid and organic amine were applied to keep good viscosity of flux for lead-free solder paste.In order to reduce the corrosion of components caused by the residue,the amount of rosin was controlled.It reduced significantly the amount of non-volatile matter.The properties of this flux were tested according to the industry standard,and compared with a flux which contains a high amount of rosin.The results show that when the amount of rosin decreased about 10 %,the amount of non-volatile matter reduced by 6 % after 260 ℃ welding,the flux is good viscosity,and it is halogen-free,nontoxic and environmentally friendly,thus it meets the needs of lead-free solder paste.