Technical Details and Frequently Asked Questions
Technical details of Miles-Platts lead-free plating:
Nickel (Ni) underlay barrier layer.
Matt tin (Sn) top layer.
Solderability test - BS 2011:Part 2.1T: 1981 (IEC 60068-2-20:1979) Test Ta - Method 1.
Frequently asked questions:
Q. What is the directive that calls for "PB Free"?
A. Directive 2002/95/EC of the European Parliament and of the council on the restriction of the use of certain hazardous substances in electrical and electronic equipment (RoHS).
Q. When will the ban on lead be enforced?
A. From 1 July 2006 for all new electrical and electronic equipment put on the market.
Q. Why has tin been chosen by Miles-Platts as the alternative to tin/lead?
A. Tin has been well proven in solderability preservative applications for many years.
Tin is easily applied to copper base metals.
Pure tin is compatible with all leaded & lead-free solders.
Q. Why matt tin?
A. Additives in the plating chemistry that are required to give a bright finish can adversely affect solderability.
Matt tin-plating technology has been developed to plate with fewer internal stresses giving a low whisker propensity.
Q. What are tin whiskers?
A. This is a phenomenon where single whiskers of tin grow out from the surface of the tin plating. These crystals have a filamentary appearance, which has led to them being referred to as "whiskers".
Q. Can Miles-Platts guarantee that the plating on their products will not grow whiskers?
A. No plating manufacturer will guarantee their technology to be whisker free. With a barrier layer of nickel and the use of matt tin plating technology the risk of whisker formation is greatly reduced. It is perceived that the threat greatly outweighs the number of failures attributed to whisker growth. It is also important to note that whiskers have also been observed on tin/lead coatings.
Q. Will Miles-Platts lead-free products be more expensive?
A. No, there will be no change to the cost of products when converted to lead-free.
Q. How will I know which of Miles-Platts products are lead-free?
A. A "Pb free" sticker will appear on the carton adjacent to the product description/quantity label.
Q. Will pure tin plating work with our existing leaded solder process?
A. Practical evidence has proven that pure tin is fully compatible with existing leaded solder processes.