Solder Paste: How To Choose The Right Pb-Free Solder

Electronic products generally have planned obsolescence and contribute to millions of tons of E-Waste. According to The World Counts only 12 % is recycled and the rest ends up in landfill or is burned. Most E-waste contains lead, which is harmful to humans, animals, and the environment. There is a worldwide push to change over to Pb-free solder in electronic manufacturing.

EU bans lead-based solder

Environmental and public safety concerns about the toxicity of lead found in solder paste propelled the European Union׳s (EU) Restriction of Hazardous Substances (RoHS) to eliminate lead-based solder in electronic production. The Australian and New Zealand governments have not legislated to remove lead from solder paste. Manufacturers can use solder paste with or without Pb.

Pb-free alternative challenges

Industry-developed Pb-free alternatives include alloys containing tin, silver, and copper.  However, there are no perfect match solutions. For instance, defence/space industries are reluctant to use Pb-free solder because of long-term concerns with “Tin Whisker” issues which can short out conductors. Pb-free solders also tend to have a higher melting point than Pb-based alloys and therefore are harder to work with.  They are also more expensive due to the higher cost of metals.

Shift to Pb-free solder

In Australia and New Zealand, CEMs are usually guided by the end-user on which solder paste is used on their PCBs. Some manufacturers use both and keep the processes separate to avoid mix-ups. Some engineers specify that they want to use a certain Pb-free paste type i.e. INDIUM 8.9HF. As consumer demand for environmentally friendly products gains momentum, more manufacturers will switch to Pb-free alternatives because using Pb-based solders will be hard to justify.

The right Pb-free solder paste

There are many Pb-free solder pastes on the market. It’s important for product developers and manufacturers to choose the right Pb-free solder paste to ensure products are reliable with fewer end-of-line defects. For more information, download the white paper from experts at Indium on how to choose the right Pb-free solder paste.

Contact our team if you have any questions about the best solder paste for your application.