Advancements in Low Temperature Lead-Free Soldering Alloys

1. Advancements in Low Temperature Lead-Free Soldering Alloys Electronic devices have become a vital part of our daily lives and soldering is a major enabler in the development of these electronic items. Refreshing the memory a bit, soldering is a process wherein, through the use of a well-designed alloy, two electronic components are connected – and the connection is electrically and thermally conductive. The joint between two components is achieved by melting this alloy and coating it over the surfaces to be joined. It is like welding, but engineered to meet the demands of very sophisticated electronics assembly processes. Normal soldering temperature is 315 °C, which is quite high. Today, there are assemblies, which require forming a connection at much lower temperatures. It is for such assemblies that low temperature lead-free solders are being developed. The specialty of these solders is that they can melt at temperatures significantly lower than even the boiling point of water. This enables soldering on highly heat sensitive materials like plastic. Research and development on low temperature lead-free solders have led to a great expansion in possibilities of soldering and applications in the electronics industry. Let’s explore more. One of the important applications that low temperature lead-free solder has made possible is step soldering. There are certain applications where successive solder joints need to be formed after setting of the initial ones. Regular solders make it difficult to achieve this, since their operating temperatures are high, which melt the previous joints. In step soldering, connections are achieved by successively using low temperature lead-free solders in order of reducing melting points. This ensures that previous joints don’t melt, and new connections are still formed effortlessly. Another aspect of low temperature lead-free solders is that they can be used on materials which are pre- molded, and are susceptible to deformation when exposed to too much heat. Plastics and fibers are two such examples. Recycling plastics and using them in printed circuit board assemblies is an environmentally noble feat that has been achieved through low temperature lead-free solders. Explore some of the best performing low temperature lead-free alloys available in the market.