Droplet Weld an Environmentally Friendly, Lead - Free Joining Technology Using Metal Droplets.

Up-coming legislation will forbid the use of lead-containing solders in the near future. Good alternatives for electrical interconnection have not been found. Alternative solder materials are much more expensive (factor 4), and have a lower though output (longer contact times of the product). Very often lead-free solders contain other environmental unfriendly components (such as bismuth and antimony). Gluing is limited to low temperature applications. Droplet weld is a novel alternative of a lead-free joining technology and this welding is using simple and low costs materials. In droplet welding a metal droplet is produced from a feed wire by local heating using a plasma arc or laser irradiation. A hot metal droplet is subsequently detached and will fall onto the parts to be joined. First tests have shown that a single hot droplet is sufficient to make a high temperature weld.