Procedure

VN

Overview

This Part 1 of the standard series IEC 62647 defines the objectives of, and requirements for, documenting processes that assure customers and regulatory agencies that ADHP electronic systems containing Pb-free solder, piece parts, and PWBs will satisfy the applicable requirements for performance, reliability, airworthiness, safety, and certifiability throughout the specified life of performance. The requirements for a Pb-free Control Plan (LFCP), hereinafter referred to as the Plan, are described in this specification, it shall also assist the Plan Owners in the development of their own Plans. The Plan documents the Plan Owner's processes that assure their customers, and all other stakeholders that the Plan Owner's products will continue to meet their requirements, given the risks stated in the Introduction. This specification does not contain detailed descriptions of the processes to be documented but lists high-level requirements for such processes, and areas of concern to the ADHP industries that shall be addressed by the processes. The control of the Pb-free activities will be accomplished by the Plan owner addressing the requirements of their customer. These activities include, but are not limited to, those performed by the system integrator, the original equipment manufacturer (OEM), and their respective supply chains, to the lowest level possible. This should be done with the knowledge that, at the component level, the aerospace industry may not have a great influence over those suppliers. In such cases, the Plan owner assumes responsibility. Some applications may have unique requirements that exceed the scope of this specification. The extended scope should be covered separately. The requirements of this specification may be tailored to address unique/specific program needs. If tailoring is performed, the user will obtain documented customer concurrence. Annex A provides a tailoring template that may be used. This document may be used by other high-performance and high-reliability industries, at their discretion. The European Union (EU) enacted two directives; 2002/95/EC Restriction of Hazardous Substances (RoHS) and 2002/96/EC Waste Electrical and Electronic Equipment (WEEE) that restrict or eliminate the use of various substances in a variety of products that are put on the market after July 2006. Other countries have also enacted similar legislation. One of the key materials restricted is lead (Pb), which is widely used in electronic solder and electronic piece part terminations. These regional regulations affect the global market place. However, due to the reduced market share of the ADHP industries, many of the lower tier suppliers to those industries will change their products to serve their primary, non-ADHP markets. Additionally, several United State (US) states have enacted similar "green" laws and many Asian electronics manufacturers have recently announced completely green product lines. Since ADHP is one of the few major industrial sectors that still repair Circuit Card Assemblies (CCAs) and the Pb-free materials and processes are relatively immature and not fully understood, an aerospace-wide approach to their application is desired. ADHP companies may be developing and/or managing Pb-free electronics and whose products fall into one of the five categories below: 1) Products that have been designed and qualified with traditional tin-lead (SnPb) electronic piece parts, materials, and assembly processes, and that will need to be maintained in the SnPb configuration; 2) Products that have been designed and qualified with traditional SnPb electronic piece parts, materials and assembly processes, and have incorporated Pb-free electronic piece parts; 3) Products that have been designed and qualified with SnPb materials, and are re-designed and requalified with Pb-free materials; 4) Products that have been designed and qualified with Pb-free electronic piece parts, materials, and assembly processes, and that will need to be maintained in the Pb-free configuration; 5) Commercial-Off-The-Shelf (COTS) assemblies built with Pb-free materials. The risks with Pb-free technology include: 1) For some service conditions, use of Pb-free solder may compromise electronic interconnection performance due to potential differences in fatigue characteristics under thermal cycling and vibration relative to traditional solders. 2) Use of Pb-free surface finishes such as pure tin can lead to the formation of tin whiskers which in turn can result in various levels of product and system failure. 3) Higher processing temperatures associated with Lead-free solders. The responsible committee is K 684 "Prozessmanagement für Avionik" ("Process Management for Avionics") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.

Document: references other documents

Document: referenced in other documents

Responsible national committee

DKE/K 682 - Aufbau- und Verbindungstechnik für elektronische Baugruppen