May 16, 2011 
Nihon Superior Co. Ltd., a supplier of advanced soldering materials to the global market, announces that Keith Howell, Technical Director for the Americas, will present during the SMTA Ohio Valley chapter meeting on June 3, 2011 at the Dave and Busters in Hilliard, Ohio.
The meeting will take place from 10 a.m.-2:30 p.m. with lunch served from 12-12:45 p.m.
From 12:45-2:30 p.m., Keith will present “Trends in Lead-free Solders and Concerns with Tin-Whiskers.”
Nearly five years after the implementation of the European Union RoHS Directive mandating the use of Pb-free solders in consumer electronics, it is becoming increasingly apparent that the simple ternary SAC305 alloy cannot deliver everything that the electronics industry requires in a solder in terms of cost and performance. The cost of the 3-4 percent Ag required to get the 217°C solidus temperature that was one of the main reasons for choosing the Sn-Ag-Cu eutectic has prompted the industry to reduce the Ag content as low as 0.1 percent Ag or to use Sn-Cu based alloys with no Ag. The non-eutectic behavior of nominally eutectic alloys that can result in dull, cracked solder fillets is being addressed by alloys such as SN100C with trace additions of Ni to Sn-Cu.
Since the move to lead-free solders that typically have a tin content of more than 95 percent, there has been concern about the possibility of circuit malfunctions due to growth of tin whiskers. There is a widely accepted view that whisker growth is a response to compressive stress within the tin crystal so that an effective mitigation strategy should be the identification and elimination or at least minimization of the processes that can generate such stress. Corrosion has been identified as one source of that stress. The likelihood of whisker growth occurring on lead-free assemblies soldered using no-clean technologies can be significantly reduced by using a halogen-free flux that does not promote the sort of corrosion that appears to be a driver for whisker growth.
Keith Howell has 25+ years of industry experience including 20 years in the field of electronics assembly and soldering. He has been in various roles in the development, manufacturing and marketing of new products and is currently Technical Director for the Americas for Nihon Superior, the developer of SN100C lead-free solder. He has a BS in Mechanical Engineering from the University of Illinois and a MBA from the University of Rochester, and has presented at numerous seminars on lead-free soldering.
If interested in attending the upcoming SMTA Ohio Valley chapter meeting, e-mail bcrane@bird-technologies.com or arrive at Dave and Busters from 9:30-10 a.m. on June 3 to register onsite.
Nihon Superior was founded in 1966 when it began marketing unique flux products imported from the US. The company made its mark on society by gathering the most advanced soldering and brazing technologies and products from around the world, and supplying them to companies in the metal-joining industry. A turning point for the company came when it started developing its own soldering materials and with the success of its unique SN100C lead-free solder alloy Nihon Superior has become a major player in the global market. To support the growing demand for its products Nihon Superior has established manufacturing and sales centers in Japan, China and other Asian countries and formed business partnerships with companies in other markets.
