What is the composition of solder paste used for reflow soldering process?
What is the composition of solder paste used for reflow soldering process? The solder paste We use a lead free soldering paste with a composition of 96,5% tin, 3% silver, 0.5% copper available in 100g cans and conforming to RoHS requirements, and containing a flux according to EN ISO 9454:2016, 1231; DIN EN 61190-1-3 / IPC J-STD-004B, REL0. What causes solder balls during reflow? Solder balls can be ejected from the joint area during soldering due to excessive outgassing of the PCB. It is caused by squeeze out of the tin/lead from under the solder mask. or just simple adhesion....