GB/T 31474-2015

This standard specifies the classification, technical requirements, test methods, and inspection rules for soldering fluxes used in high-reliability electronic assemblies, such as those in aerospace, military, and telecommunications equipment. It is applied in the manufacturing and quality control of printed circuit board (PCB) assemblies where flux residues must be minimized to ensure long-term electrical reliability and corrosion resistance. The standard is particularly relevant for processes involving lead-free soldering and fine-pitch components in demanding operational environments.