There are many factors that can affect the final quality of the SMT patch, such as: the quality of the patch components, the quality of the pads of the pcb circuit board, solder paste, solder paste printing, the placement accuracy of the placement machine, Furnace temperature curve adjustment for reflow soldering, etc. So, author from qihe smt pick and place machine tell you about the most commonly used auxiliary materials in SMT patches: how to choose solder paste and flux?