Indium Blog

Lead Free Alloy Selection

Ignoring the solder selection as part of your design process is risky business. 

 

 

As Terry Costlow, the IPC online editor of EMS Now noted in an article ‘Controlling the Explosion of Lead Free Solders’, the choice of the right solder alloy can affect the manufacturing process, the cost, and the field performance of the product.

 

 

Initially it was thought that the move to Pb free solders was just a matter of changing reflow profiles but major issues such as tin whiskers, brittle intermetallic layers and other concerns soon pushed solder selection into the forefront.

 

 

With over 200 published alloys and over 300 custom alloys shipped each year, we have seen the need for considering the solder design first.  Before you settle on a solder you have to consider:

·         Surface metallizations

·         Operational temperature of your product or device

·         Form of the solder you want to use (solder paste, solder preform, solder wire, etc.)

·         Temperature of subsequent soldering steps

·         Thermal coefficient of expansion

·         Tensile strength

 

 

And these are just a few of the considerations.  Let us help you make the right selection.  Contact us at: askus@indium.com.

 

 

Feel free to discuss solder selection with our industry professional, Dr. Lasky on November 11th, IPC is having a materials conference: Engineering for Compliance in Irvine, CA.