By John McHale
BOSTON - U.S. Department of Defense (DOD) and industry experts will discuss procedures and methods for dealing with lead-free compliance at the Military Technologies Conference (MTC 2007) on March 27 and 28 in Boston. The two presentations will be part of the conference’s opening session March 27.
The first presentation is from Anthony J. Rafanelli, an engineering fellow at Raytheon Integrated Defense Systems, and Lloyd Condra, Technical Fellow at Boeing Phantom Works on “A Protocol for Reliability Testing of Aerospace and High-Performance Lead-Free Electronic Assemblies.”
“Under the facilitation of the Aerospace Industries Association, the Government Electronics Industries Association (GEIA) has stood up a team whose charter is to generate a document with two objectives: define a default method for reliability testing of AHP products containing lead-free solder; establish a protocol for designing, conducting, and interpreting results from reliability tests,” the presenters state.
This presentation will report on the progress of this team and present information on each of the objectives in an effort to solicit feedback. The presentation will also discuss the diversified team membership and those aerospace and defense perspectives that each brings to the process.
A team from Naval Surface Warfare Center, Crane Division, will present “Methodology for Evaluating Data for ‘Reverse Compatibility’ Solder Joints.” The authors of the paper are Dennis Fritz-SAIC, Christian Navarro-Purdue Calumet, Carol Handwerker-Purdue, Lafayette, Bill Russell-Raytheon, Gary Latta-Navy Crane, and Andrew Ganster-Navy Crane.
The Navy authors state that “particular attention is being paid today to lead-free components and/or solder alloys being used to repair legacy military electronics. Military hardware, manufactured for decades with eutectic tin/lead solder, is now being caught up in the global shift to lead-free solder. A “backward compatibility” problem occurs as parts suppliers due to market concerns (military is less than 5 percent of market share) eliminate eutectic tin/lead solder as a component finish substituting other finishes (usually electroplated matte tin) on existing part numbers.
“In addition, the proliferation of commercial of the shelf (COTS) hardware into military systems greatly increases the probability of mixing tin/lead and lead-free solders and component finishes within the assembly during repair,” the presenters state. “The intermixing of tin/lead and lead-free solders raises long-term reliability issues that are yet unanswered. A large database of information was assembled from publicly available data on mixed solder assembly. Methodology was developed for comparing information sources by analyzing Weibull reliability charts for data consistency. Using these comparisons, reliability predictions are made for mixed solder assembly of military electronics, to guide rework and repair options and making informed decisions possible.”
MTC 2007 also has three focused modules lead by industry leaders: Networking on the Move, which focuses on the design challenges in providing non line-of-sight communications to military units on the move; Software Implementation for Open Architectures, which discusses how military program managers today adapting legacy code and legacy systems to modern open architectures that are independent of hardware; and Thermal and Power Management Trends for Military Electronics, which covers the challenges and solutions in managing the power and thermal burdens modern high-performance electronics place on military platforms.
The conference will be at the Hynes Convention Center in Boston. For more information, please visit www.miltechconference.com.