Solder POS-61– this tin-lead solder. POS-61 - low-temperature, soft solder. The material that is used when soldering (joining) various workpieces. It has a lower melting point than the joining metals. It is widely used when working with products of small size or made of low-melting metals. Tin-lead solders (POS) are widely used in all areas of industry.
They have low corrosion resistance in a wet environment, so soldered joints are protected by paint coatings. They have high technological properties, are plastic and do not require expensive equipment when soldering. Soldering with tin-lead solders is usually done by heating with a soldering iron(//tractor-service.com)
The content of tin in such solder is 59-61%, the rest is due to lead and impurities. The melting point of POS-61 is 183-191ºС