190 likes | 365 Views
Update on the ESA Lead Free Control Plan (LFCP) Working Group. Barrie Dunn barrie.dunn@esa.int May 2011. Main Objective of the Working Group. Main Objective of the Working Group is to publish a “Lead-free Control Plan” (LFCP) that can be used by the Space Industry in order to:
E N D
Update on the ESA Lead Free Control Plan (LFCP) Working Group Barrie Dunnbarrie.dunn@esa.intMay 2011 ESA UNCLASSIFIED – For Official Use
Main Objective of the Working Group • Main Objective of the Working Group is to publish a “Lead-free Control Plan” (LFCP) • that can be used by the Space Industry in order to: • ensure that spacecraft electrical systems and related hardware comply with the contractual requirements of ECSS standards, and, • assess the inherent risks with Pb-free • As of May 2011, the Plan is about 60% complete • Intention is to publish it as an ESA STR document (not a Standard, but a “good practice” document, parts of which could be formalised in the future as requirements) ESA UNCLASSIFIED – For Official Use
Secondary Objectives : • To exchange, share information, return of experience concerning Lead-Free • To identify the issues and problems to be solved regarding the concerns expressed by the CTB members • To define recommendations for solutions and answers to these concerns • The scope includes: • EEE components and COTS devices • Connectors • PCBs • Solder • Peripheral hardware : clamps, screws, pins, wires, electronic housings ESA UNCLASSIFIED – For Official Use
Chapter Titles for LFCP • Introduction (Chapter 1) • Problems associated with Lead-free (processes at higher temperatures, materials with different mech props, solderability, inspection criteria, whiskers, rework/repair, mixing of alloys, traceability, black pad, etc.) (Chapter2) • ESA Requirements (Chapter 3) • Definition of Pure Tin (Chapter 4) • Assessment of Suppliers’ LFCPs (Chapter 5) • Methods for detecting Tin and Lead (Chapter 6) • Method for Re-processing component terminations (Chapter 7) • Mitigation strategies for the avoidance of failures due to tin whiskers (Chapter 8) • Illustrations of problem situations (Annex 1) • Check List (for in-house awareness and auditing purposes) (Annex 2) ESA UNCLASSIFIED – For Official Use
Restriction of the use of certain hazardous substances in electrical and electronic equipment ***I A7-0196/2010 P7_TA-ROV(2010)0431 This Directive does not apply to: • equipment which is necessary for the protection of the essential interests of the security of Member States, including arms, munitions and war material intended for specifically military purposes; • equipment designed to be sent into space; • equipment which is specifically designed and to be installed as part of another type of equipment that is excluded or does not fall within the scope of this Directive, which can fulfil its function only if it is part of that equipment, and which can be replaced only by the same specifically designed equipment ; • large-scale stationary industrial tools; • large-scale fixed installations; • means of transport for persons or goods, excluding electric two-wheel vehicles which are not type-approved. ESA UNCLASSIFIED – For Official Use
Lead-free Control Plan Working Group • Flow Diagram for Plan (suggestion): 1. Procurement to define lead-free requirements 2. Incoming Inspection of components, pcbs, terminal posts, connectors Using: visual, swab (red means lead), XRF, SEM-EDAX,etc. 3. Lead-free parts may need reprocessing de-tin, pre-tin with solder, etc. per ECSS-Q-STD-70-08 4. Impossible to reprocess then a Risk Assessment is needed 5. Risk Assessment will include consideration of mitigation possibilities involving: tin composition, tin thickness, substrate material, heat treatment history, track/line spacing distance, conformal coating, environment exposure (life, temperature, cycles, etc.) ESA UNCLASSIFIED – For Official Use
Lead-free Control Plan Working Group ESA UNCLASSIFIED – For Official Use
Cross section 3 ESA UNCLASSIFIED – For Official Use
APPENDIX 2 of LFCP: CHECK LIST FOR CONTROLLING THE AVOIDANCE OF LEAD-FREE MATERIALS AND COMPONENTS ESA UNCLASSIFIED – For Official Use
Technical Tasks for WG members: Understand EU Directives Risks and Limitations with Lead-free such as: tin whiskers, solder joint reliability, copper dissolution, cross contamination, higher processing temperatures (most of these have been researched with answers available and some have been identified for small studies by ESA) Components and other items delivered per ECSS requirements must be without pure tin – inspection methods Provide recommendations for reworking pure tin components Identify other small studies where information is missing (such as the SPUR tin chemical stripping study) Present WG Members are from: ESA (Chair), CNES, Astrium, THALES Group, SEA Ltd UK NEW MEMBERS ARE WELCOME Technical Tasks for WG members: ESA UNCLASSIFIED – For Official Use
Link between LFCP & PSWG ad hoc WG on “Pb free incoming inspection test ESCC ECSS Cooperation on Q-60 discipline SCSB Technical Authority PSWG CTB Discipline focal point Ad hoc WG on Pb free incoming inspection test Lead Free Control Plan ECSS-Q-ST-60-13 (COTS) Astrium, TAS, others procedures RNC-CNES-Q-ST-60-100 (COTS) ESA UNCLASSIFIED – For Official Use
LFCP WG Next Meetings will be in the form of small workshops at THALES, Toulouse • 15th June 2011“Re-processing of component terminations” based on existing Thales and Astrium experiences and novel ideas from industry • 22nd September 2011: “Risk Assessment and Mitigation associated with lead-free and whisker growths” based on existing computer programmes and novel ideas from industry • INPUTS from both Workshops will be used for the LFCP Chapters 6, 7 and 8 • All Component and Materials specialists are invited to attend, contact: • Barrie.Dunn@esa.int or • Augustin.Coello-Vera@alcatelaleniaspace.com ESA UNCLASSIFIED – For Official Use