About Usmore

About us
 Shenzhen KingshengPCBA Tech Co.,Ltd (HK C-Alley Co.,Ltd), an professional PCBA manufactuer and electronics manufacturing service (EMS) provider for 12years.SMT factory has ISO9001, ISO14001, TS16949 certification, advanced production equipment and rich experience in the production of PCBA. more

PCBA Solder formulations
PCBA Solder formulations

Common solder formulations based on tin and lead are listed below. The fraction represent percentage of tin first, then lead, totaling 100%:
 
63/37: melts at 183 °C (361 °F) (eutectic: the only mixture that melts at a point, instead of over a range)
60/40: melts between 183–190 °C (361–374 °F)
50/50: melts between 183–215 °C (361–419 °F)
For environmental reasons (and the introduction of regulations such as the European RoHS (Restriction of Hazardous Substances Directive)), lead-free solders are becoming more widely used. They are also suggested anywhere young children may come into contact with (since young children are likely to place things into their mouths), or for outdoor use where rain and other precipitation may wash the lead into the groundwater. Unfortunately, most lead-free solders are not eutectic formulations, melting at around 250 °C (482 °F), making it more difficult to create reliable joints with them.