Applied Reliability for Industry 2

Abdelkhalak El Hami is Full Professor of Universities at INSA-Rouen-Normandie, France. He is the author/co-author of several books and is responsible for several European pedagogical projects. He is a specialist in fluid structure interaction and problems of optimization and reliability in multi-physical systems.David Delaux is Reliability Director at Valeo and Reliability Senior Expert. An Honorary Visiting Professor at Bradford University, UK, he is also a national auditor/assessor at COFRAC (ISO 17025), President of the European Campus of Statistics Statistical Analysis For Industry (SAFI), Expert for the European Innovation Council and President of the association ASTE. He is also the former President of the European Reliability Environmental Confederation (CEEES).Henri Grzeskowiak is a Technical Expert at Matra BAe Dynamics and MBDA (missile). He is also an auditor at COFRAC, Head of Department of Environmental Engineering (Matra & MBDA) as well as former President of the Standardization Committee for Mechanical & Climatic Environment (DGA) and of the association ASTE (France) and CEEES (Europe).

• Foreword ixPhilippe EUDELINEPreface xiAbdelkhalak EL HAMI, David DELAUX and Henri GRZESKOWIAKChapter 1 Aggravated Testing 1Henri GRZESKOWIAK, David DELAUX and Abdelkhalak EL HAMI1.1 Introduction to aggravated (or highly accelerated) testing 11.2 Background 11.3 General approach 31.3.1 Robustness and reliability 51.4 Types of products affected by aggravated tests 81.5 Aeronautical sector example: effect of aging on the SOA (safe operating area) 131.6 Typology of precipitated defects in HALT tests 141.7 Carrying out tests with HALT machine’s pneumatic hammers: inherent particularities and precautions 161.8 Comparing vibration fatigue of HALT versus ALT testing 231.8.1 Presentation of the adopted approach 231.8.2 The fatigue damage spectrum 241.8.3 Automotive case study: inverter/converter failure 281.8.4 Comparison of accelerated and aggravated tests 381.8.5 The standards 401.9 References 41Chapter 2 Fatigue Damage Analysis and Reliability Optimization of Structures Subjected to Random Vibrations 47Ahmed YAICH and Abdelkhalak EL HAMI2.1 Introduction 472.2 Fatigue damage analysis 482.2.1 Formulations and developments 482.2.2 Fatigue damage analysis strategy 512.3 Reliability optimization of structures subjected to random vibrations 522.3.1 Deterministic design optimization 522.3.2 Reliability-based design optimization 532.3.3 Reliability optimization of structures subjected to random vibrations 622.4 Applications 642.4.1 Description of the problem 642.4.2 Results and discussion 672.5 Conclusion 712.6 References 72Chapter 3 Accelerated Testing 77Henri GRZESKOWIAK, David DELAUX and Abdelkhalak EL HAMI3.1 The different types of tests 773.1.1 The calculations 783.1.2 The simulations 783.1.3 The tests 793.1.4 Links between the three types of demonstrations 803.2 General information on accelerated testing 803.2.1 The experimental models 833.2.2 Statistical models 833.2.3 The physical models 833.3 The principle, methodology and implementation of accelerated testing 833.3.1 Definition and key concepts 843.3.2 Evaluating the predictive reliability of a system by performing tests 863.3.3 Accelerated tests (based on the physical model): example of temperature acceleration 883.3.4 Evaluating the predicted reliability of a system in relation to an imposed lifetime and environmental constraints 883.3.5 Humid heat 903.3.6 Temperature 913.3.7 Multi-stress laws 923.3.8 Accelerated testing in practice 923.3.9 Reliability assessment for wear-and-tear related failure mechanisms 933.3.10 Conclusion of section 943.4 The different phases of building a reliability validation plan 953.5 Development of a corrosion environment test for automotive heat exchangers 973.6 Accelerated testing standards 1073.7 Conclusion 1093.8 References 109Chapter 4 Collection of Standards NF 50-144-1 to 6: The Consideration of Environment in the Product Lifecycle 113Henri GRZESKOWIAK, David DELAUX and Abdelkhalak EL HAMI4.1 Introduction 1134.2 Presentation of AFNOR NF 50-144-1 to 6 1144.3 Focus on NF X50-144-3 1194.3.1 The four steps of the methodology 1204.3.2 Focus on step 3: the DBM 1264.3.3 Focus on step 3: illustrations of the disjointed blocks method 1344.3.4 Example of test customization for the A400 M aircraft 1404.5 References 143Chapter 5 Development of Vibration Specifications for Powertrain Components 145Marco BONATO5.1 Introduction 1455.1.1 Combustion engine vibration 1465.2 Types of vibration signals for validation testing 1485.2.1 Conventional signals used in the automotive industry 1485.2.2 Validation tests for engine mounted heat exchangers 1485.2.3 Recent developments: customizing vibration specifications 1495.2.4. The FFT method: test signal in PSD form and sinusoidal sweep 1505.2.5 The customized test method 1515.3 Case study: vibratory specification for a water-cooled WCAC 1535.3.1 Vibration signals: PSD and sinusoidal sweep 1545.4 Development of a signal more representative of the real-world environment 1565.4.1 Multi-sine sweeps over noise 1575.4.2 Comparison with existing methods 1595.4.3 Subsequent work 1605.5 References 160Chapter 6 Improving Accelerated Reliability Testing by Using Optimized Signals 163Jonathan MARTINO6.1 Introduction 1646.2 General considerations 1656.2.1 Multi-sine signals 1666.3 Kurtosis and CF 1706.3.1 Kurtosis 1706.3.2 Crest factor 1716.4 Optimization of multi-sine pseudo-random signals 1726.4.1 Controlling the CF by optimizing the phase shifts 1726.4.2 Preliminary treatment 1736.4.3 Analytical determination 1746.4.4 Numerical methods 1746.4.5 Stochastic distribution of signals with low CF 1756.4.6 Use of optimized low-peak signals for environmental testing 1766.4.7 Kurtosis control through non-linear manipulation 1786.4.8 Duality between kurtosis and CF 1796.5 Damage assessment 1826.5.1 Fatigue damage spectrum 1826.5.2 Reducing the test duration 1866.5.3 Influence of signal optimization in damage assessment 1866.6 Conclusion 1926.7 References 193List of Authors 197Index 199Summaries of other volumes 203