Guest Editorial -For Plateworld.com

 Don Baudrand, Don Baudrand Consulting,   e-mail:donwb@tscnet.com

GET THE LEAD OUT

The regulations imposed on industry to remove lead from just about everything, is causing a surge of research and adaptation. Solder can no longer contain lead. All the industries that use tin-lead solder must change. The cost and difficulties in replacing lead have been and continue to be tremendous. The melting point of most of the practical alloys that substitute for lead is higher and the cost is higher also. For electronic devices the higher melting temperature often means major redesign of components.

The plating industry must reformulate alloys for so called solder plating by substituting other metals for the traditional lead.

Electroless nickel plating solutions have long used lead as a stabilizer for the plating solutions. Lead is used at concentrations of between 0.3 parts per million (ppm) to as high as 2 ppm. Lead happens to be one of the best, if not the best stabilizer for electroless nickel solution. What to substitute? Metals such as arsenic, antimony, cadmium, selenium, and thallium are stabilizers that work reasonably well, but because of their toxicity cannot or should not be used. What then shall we use? The replacement of lead has been the subject of a great deal of research done by all the major suppliers of electroless nickel worldwide. The problem is world wide because users of electroless nickel need to compete in the same markets. Therefore must comply.

My recent experience using lead free electroless nickels has been less than satisfactory. As a consultant I have encountered lead free electroless nickel solutions that do not perform well. Instability is the major problem. I am confident that plating suppliers will solve this problem, but at a significant cost. I think some have already succeeded. The result of the changes needed to replace lead electroless nickel solutions may become more specialized. That is, more closely tied to specific application needs. One formula will no longer have a multiplicity of applications. Instead of having high-phosphorus, mid-phosphorus and a low-phosphorus formulas, additional formulas may be needed to fit specific applications.

Electroless nickel alloys are finding new applications. Some of the alloy constituents contribute to stability and help solve the no lead problem. Also co-deposition of some of the particulate matter added for co-deposition to alter the surface characteristics aid in stabilization. Some add to the problem

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