The EMPF has initiated a new lead free soldering project entitled Lead Free Manufacturing for Navy Systems, developed in response to environmental legislation which aims to eliminate the use of lead (Pb) in electronics manufacturing in the next few years. The program’s goals are two-fold:

1. Demonstrate the viability of lead free solders and finishes in high reliability aerospace and military applications by assembling and certifying functional hardware for use in Naval systems.

2. Document the methodology and processes by starting the creation of a Lead Free Soldering Implementation Guideline to support the high reliability applications of the Navy and DoD. The guideline will be available in early 2006.

The longer term goals of the efforts in Lead Free Manufacturing Technology are to eventually qualify these materials and processes for use in high reliability Defense applications. This program will be the first step toward that end. Lead free soldering is the next major technology driver in electronics manufacturing. Legislation already passed in Europe and Asia requires commercial electronics manufacturers to convert their tin lead soldering processes to lead free by July 2006. In the United States, legislation has been proposed which would ban the use of lead in electronics, but none has been signed into law. There have been efforts to control the use of lead in this country through environmental executive orders and EPA regulations, so the trend clearly points towards legislative-imposed elimination of its use at some point in the future.

Due to the small size of the military electronics sector – less than 1% of the total – it is inevitable that the manufacturing of high reliability military electronic components and assemblies will be significantly impacted by the worldwide demand for lead free manufacturing by the much larger commercial sector. This demand may be driven by legislation not directly related to military applications, but it will eventually impact the availability of lead-based components and materials used in the manufacturing of military hardware. This new EMPF project is a proactive attempt to identify the unique lead free manufacturing challenges related to the defense electronics sector and to provide guidelines for the effective transition of existing practices for the manufacturing of high reliability military electronics systems.

The EMPF’s Lead Free Manufacturing for Navy Systems program will investigate this aspect of the lead free transition with assistance from members of its Industrial Advisory Board (IAB). The IAB consists of major defense electronics manufacturers, including Boeing, Rockwell Collins, ITT, Raytheon, Honeywell, and Lockheed Martin. Each participant in the project will build and test functional deliverable hardware manufactured with lead free solders and component finishes. The program’s stakeholder is the F-18 Program.

The 3 major efforts of the project focus on the following:

1) Research data evaluation
2) Process definition
3) Process and product certification

The deliverables of the project are the data set leading to the alloy selection for Navy use; the process definition; and the Lead Free Soldering Implementation Guideline.

Research data evaluation
The team must be aware of, evaluate, and factor in the myriad of research data that exists and currently supports the recommendation of lead free solder alloys for use on Navy platforms and applications.

Process definition
The team will demonstrate at the EMPF’s Demonstration Factory a qualified, standard lead free soldering manufacturing process and lead free soldering rework and repair process, using a recommended alloy which aerospace and military electronics manufacturers can choose to implement within their factories and depots.

The EMPF will perform a series of analyses of selected lead free solders in concert with the solder manufacturers. The goal is to assist solder manufacturers with the development of lead free soldering materials for military requirements. The EMPF will generate and present a standard to the military and aerospace communities, to track the solders, board finishes, and component finishes used on deliverable hardware.

Figure 1-2 – The EMPF’s Lead Free Soldering Technology Readiness Level Roadmap

It is inevitable that lead free solders and component finishes will be introduced into the manufacturing of military systems. The EMPF has developed a Lead Free Soldering Technology Readiness Level Roadmap (Figure 1-2). It is estimated that both aerospace and military systems will be lead free by 2008. This estimated time frame may be pulled in, depending upon the continued availability of tin lead components and customer requirements. To meet this 2008 time frame, functional lead free hardware will have to undergo Environmental Stress Screening (ESS) prior to production. This will ensure that the reliability of lead free soldered hardware is equivalent to or better than tin lead soldered hardware. Depending upon program requirements, the ESS testing can take up to one to two years to complete.

The Lead Free Manufacturing for Navy Systems project is an excellent example of the EMPF’s role in identifying critical manufacturing issues affecting the Navy’s electronics systems being used in both air and sea platforms around the world. It is also a powerful statement about the EMPF’s continuing connection with its industry partners and the leveraging of the collective resources to insert manufacturing technology improvements into existing Navy systems to positively impact affordability, performance, and reliability. The results of this project will become even more critical as tin lead solders and component finishes become less available as the worldwide electronics industry converts to lead free technologies.

For more information concering Lead Free processes and surrounding issues, please stop by ACI's new Lead Free Manufacturing Page to download articles contributed to ACI by some of the industry's most knowledgable individuals and organizations, as well as material generated by ACI, and documents on the legislation surrounding the Lead Free issue.