BS EN 61163-1-2006 Reliability stress screening - Part 1 Repairable assemblies manufactured in lots《可靠性应力筛分 第1部分 批制造的可修复组件》.pdf

1、Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 03:07, Uncontrolled Copy, (c) BSIg49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58m

2、anufactured in lotsThe European Standard EN 61163-1:2006 has the status of a British StandardICS 31.020Reliability stress screening Part 1: Repairable assemblies BRITISH STANDARDBS EN 61163-1:2006BS EN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 03:07, Uncontrolled

3、Copy, (c) BSIThis British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 August 2007 BSI 2007ISBN 978 0 580 54071 4Amendments issued since publicationAmd. No. Date Commentsrequest to its secretary.This publication does not purport to include all the n

4、ecessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard is the UK implementation of EN 61163-1:2006. It is identical to IEC 61163-1:2006. It supersedes

5、 BS 5760-16-1:1996 which is withdrawn.The UK participation in its preparation was entrusted by Technical Committee DS/1, Dependability and terotechnology, to Subcommittee DS/1/1, Dependability.A list of organizations represented on this committee can be obtained on EUROPEAN STANDARD EN 61163-1 NORME

6、 EUROPENNE EUROPISCHE NORM December 2006 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2006 CENELEC - All rights of exploitati

7、on in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61163-1:2006 E ICS 03.120.01; 03.120.30; 21.020 English version Reliability stress screening Part 1: Repairable assemblies manufactured in lots (IEC 61163-1:2006) Dverminage sous contraintes Partie 1: Assemblages rpa

8、rables fabriqus en lots (CEI 61163-1:2006) Zuverlssigkeitsvorbehandlung durch Beanspruchung Teil 1: Instandsetzbare Baugruppen, losweise gefertigt (IEC 61163-1:2006) This European Standard was approved by CENELEC on 2006-11-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regula

9、tions which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This

10、 European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members

11、 are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sw

12、eden, Switzerland and the United Kingdom. Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 03:07, Uncontrolled Copy, (c) BSIForeword The text of document 56/1102/FDIS, future edition 2 of IEC 61163-1, prepared by IEC TC 56, Dependability, was submitted to the IEC-CENELEC parallel vo

13、te and was approved by CENELEC as EN 61163-1 on 2006-11-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2007-08-01 latest date by which the national standards conflicting

14、with the EN have to be withdrawn (dow) 2009-11-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 61163-1:2006 was approved by CENELEC as a European Standard without any modification. _ 2 EN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA S

15、TANDARDS, 05/12/2007 03:07, Uncontrolled Copy, (c) BSI 3 CONTENTS INTRODUCTION.6 1 Scope 9 2 Normative references .9 3 Terms and definitions .11 4 Symbols .13 5 General description 13 5.1 The reliability stress screening principle.13 5.2 Failure categories15 5.3 Time of occurrence of failures16 6 Pl

16、anning.16 6.1 Stress conditioning 16 6.2 Evaluation of the failure-free period TM18 6.3 Time graphs for determination of the failure-free period20 7 Pilot-production screening 25 7.1 General .25 7.2 Collection of information 25 7.3 Evaluation of information .25 7.4 Re-evaluating the failure-free per

17、iod TM.26 8 Mature production screening.27 8.1 General .27 8.2 Collection of information 27 8.3 Evaluation of information .27 8.4 Dealing with discrepancies.27 8.5 Eliminating reliability stress screening29 Annex A (informative) Stress conditions General information .30 Annex B (informative) Stress

18、conditions Temperature 33 Annex C (informative) Stress conditions Vibration and bump37 Annex D (informative) Stress conditions Humidity 43 Annex E (informative) Stress conditions Operational stress46 Annex F (informative) Voltage stress48 Annex G (informative) Highly accelerated stress screening .49

19、 Annex H (informative) Bimodal distributions Weibull plotting and analysis 50 Annex I (informative) Evaluation of the failure-free period and the average screening duration56 Annex J (informative) Worked example.66 Annex ZA (normative) Normative references to international publications with their co

20、rresponding European publications81 Bibliography .80 EN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 03:07, Uncontrolled Copy, (c) BSI 4 Figure 1 Conceptual difference between reliability screening and growth.7 Figure 2 Typical flow for the design and modifications o

21、f reliability stress screening processes for repairable assemblies .8 Figure 3 Typical flow of hardware assemblies from the component manufacturer to the end user .10 Figure 4 Reliability stress screening of repairable assemblies.14 Figure 5 Dependency of categories of failures 16 Figure 6 Elements

22、of stress conditioning 16 Figure 7 Assembly showing screening duration.18 Figure 8 Time graphs for the determination of the failure free period 21 Figure 9 Example of an experimentally determined Weibull curve that is levelling off at p % failures 26 Figure H.1 The S-curve for a bimodal Weibull dist

23、ribution mixed by and in the proportions 15 % and 85 %, respectively .51 Figure H.2 Estimation of p, 1 and 1 for the purpose of reliability screening optimization52 Figure H.3 The c.d.f. curves for bimodal exponential distribution.54 Figure H.4 The hazard rate function for bimodal exponential distri

24、bution .55 Figure I.1 The basic system .56 Figure I.2 An assembly surviving the screening period TM with REn remaining weak components .58 Figure I.3 Possible states when a component fails during the stress screening58 Figure I.4 Assembly states after failure and repair 58 Figure I.5 Time graph for

25、evaluation of the failure-free screening period60 Figures I.6a and I.6b Average screening duration versus the normalized failure-free period F1MmT pc= 0,000 5 and pc= 0,001. 62Figures I.6c and I.6d Average screening duration versus the normalized failure-free period F1MmT pc= 0,002 and pc= 0,005 63F

26、igures I.6e and I.6f Average screening duration versus the normalized failure-free period F1MmT pc= 0,015 and pc= 0,02 64 Figures I.6g and I.6h Average screening duration versus the normalized failure-free period F1MmT pc= 0,03 and pc= 0,04 . 65 Figure J.1 Derivation of the failure-free period TM69

27、Figure J.2 Derivation of the average screening duration71 Figure J.3 Weibull plot of the observed and predicted failure pattern for the pilot production PBAs.74 11)( = etF5,130- t21)( = etF100060- tEN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 03:07, Uncontrolled C

28、opy, (c) BSI 5 Figure J.4 Weibull plot of relevant failures and predicted S-curve for the pilot production screening 76 Figure J.5 Time graph (corrected) for determination of the failure-free period77 Figure J.6 Time graph (corrected) for evaluation of the screening duration78 Table A.1 Stress types

29、 Indication of cost of application31 Table J.1 Relation between sensitivity of flaws and stresses.68 Table J.2 Observed failure ranks and times to first failure for the pilot production 72 Table J.3 Revised rank values75 EN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/200

30、7 03:07, Uncontrolled Copy, (c) BSI 6 INTRODUCTION Quality control and good design are prerequisites for reliability. However, in cases where an assembly has an unacceptably low reliability in the early failure period, a reliability screening process may be necessary. An unacceptably low reliability

31、 level can be different from one customer to another, or can be based on general market requirements. Reliability stress screening (RSS) and reliability growth programmes both aim at improvements in the reliability found by the user. However, the two methods are different in principle: a reliability

32、 growth programme is a development activity, the purpose of which is to improve the inherent reliability performance of the assemblies by effecting changes to the design (see IEC 61014 and IEC 61164); the purpose of reliability stress screening is to detect and remove flaws; it is part of the produc

33、tion process, and should not be relied upon to reveal inadequacies in design. Furthermore, the two methods affect the reliability performance differently. This is illustrated in Figure 1. In principle, a reliability screening programme “cuts away“ the early failure period (or part thereof), while a

34、reliability growth programme reduces the overall failure rate level. A reliability growth programme may affect the need for a reliability screening programme if the flaws are of such a nature that they can be prevented from being present at all. The user of this standard should be aware that reliabi

35、lity stress screening does not improve the intrinsic reliability of the assemblies under consideration and, where possible, should be made unnecessary by reliability growth programmes and/or quality control. In this standard the term “Item” is used when it is not necessary to distinguish between com

36、ponents, assemblies and system(s). The specific purpose of carrying out a reliability screening process is to detect and remove flaws in hardware assemblies before they reach the customer, or are assembled into higher-level products. This means that, in principle, every hardware assembly under consi

37、deration should be included when a reliability screening process is introduced into a production process. Reliability screening may cover hardware assemblies of different types and at different levels of the manufacturing process. This standard covers composite items assemblies which are intended to

38、 be repaired. Once the allowable fraction of weak assemblies has been specified, the methods in this standard lead to the most economical screening process for assemblies that are manufactured in lots. This is because not all types of assemblies need to be subjected to a reliability screening proces

39、s. Only the types of assemblies likely to contain flaws should be included. Furthermore, the extent (stress conditions, duration, etc.) to which these selected assembly types will be subjected to screening needs to be minimized. In reliability stress screening the flaws are precipitated into failure

40、s by exposure of the assemblies to a suitable stress, for example environmental stress, operational stress, or a combination of these. Reliability stress screening is often called environmental stress screening (ESS). EN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 0

41、3:07, Uncontrolled Copy, (c) BSI 7 If rogue components are known about and proved to originate in the component manufacturing process, it is much more effective to use screening e.g. burn-in of the rogue components in question instead of the assembly. However screening a component cannot remove flaw

42、s introduced in the assembly process (e.g. soldering, handling (ESD) etc.). The typical steps in a reliability stress screening process are illustrated in Figure 2. Equipment version AFailure pattern beforereliability improvementsare introducedFailure rate0 Time to first failure0 Time to first failu

43、reEquipment version AFailure pattern afterreliability screening Failure rateRemaining failures are causedby remaining flaws and systematic weaknessesReliability screening IEC 61163 seriesPart “cut“ awayby reliability screeningApplicable to hardwarecontaining flaws0 Time to first failureEquipment ver

44、sion BFailure pattern beforereliability improvementsare introducedFailure rateRemaining failures are caused by residual weakness (including flaws)Overall level reducedby reliability growthReliability growth IEC 61014Applicable to hardware and software containingsystematic weaknessesNOTE This standar

45、d addresses reliability screening only. For reliability growth see IEC 61014 and IEC 61164. Figure 1 Conceptual difference between reliability screening and growth IEC 1026/06 EN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 03:07, Uncontrolled Copy, (c) BSI 8 StartSp

46、ecify the maximumallowable fraction of weakassembliesJ.2 step 1Evaluate the actualfraction of weakassembliesJ.2 step 2Is the actual fractionof weak assembliesequal to or lower than thespecified value?NoYesReliability stresssrceening is notnecessary8.5 and J.2 step 2StopPerform the reliability stress

47、 screening, collect and analyse the failure informationgenerated6.3, 7, 8 and J.3Design of modify (if necessary)the reliability stressscreening6.2 and J.2 step 3 to step 5Reliability stressscreening is necessaryJ.2 step 21)The result of the analysis of the failure causes may be used in a reliability

48、 growth and quality control programme. Figure 2 Typical flow for the design and modifications of reliability stress screening processes for repairable assemblies 1) IEC 1027/06 EN 61163-1:2006Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 05/12/2007 03:07, Uncontrolled Copy, (c) BSI 9 RELIAB

49、ILITY STRESS SCREENING Part 1: Repairable assemblies manufactured in lots 1 Scope This part of IEC 61163 describes particular methods to apply and optimize reliability stress screening processes for lots of repairable hardware assemblies, in cases where the assemblies have an unacceptably low reliability in the early failure period, and when other methods, such as reliability growth programmes and quality control techniqu