Probabilistic Physics of Failure Approach to Reliability

Preface xi 1 Overview of Probabilistic Physics-of-Failure Approach to Reliability 1 1.1 Introduction 1 1.2 Overview of Physics-of-Failure Modeling 2 1.3 Important Forms of PoF Models 4 1.4 PPoF Approach to Life Assessment 6 1.5 Accelerated Testing in PPoF Model Development 8 1.6 Organization of the Book 10 References 11 2 Summary of Mechanisms of Failure and Associated PoF Models 13 2.1 Introduction 13 2.2 Fatigue 15 2.3 Wear 60 2.4 Creep 81 2.5 Corrosion 90 References 97 3 Types of Accelerated Testing and Modeling Concepts 101 3.1 Introduction 101 3.2 Types of Accelerated Testing - Qualitative and Quantitative 101 3.3 Qualitative Accelerated Tests 102 3.4 Quantitative Accelerated Tests 107 References 115 4 Analysis of Accelerated Life Testing Data and Physics-Based Reliability Model Development 117 4.1 Introduction 117 4.2 Accelerated Life Data Analysis Methods 117 4.3 Basics of ALT Data Analysis 117 4.4 Types of Collected Accelerated Life Test Data 118 4.5 Life-stress Models 119 4.6 Probability Plotting Method for ALT Model Estimation 124 4.7 Maximum Likelihood Estimation Approach to ALT Data Analysis 131 4.8 Confidence Intervals for MLE 134 4.9 MLE Approach to Estimating Parameters of Common Distributions 136 4.10 MLE-Based Parameter Estimation for Different Life-stress Models 139 4.11 Proportional Hazards (PH) Model 168 4.12 Bayesian Estimation Approach to ALT Model Parameter Estimation 171 4.13 Determining stress dependencies 175 4.14 Summary of the ALT Steps and Common Problems in Practice 178 4.15 Time Varying Stress Tests 179 4.16 Step-Stress Analysis And Model Development 182 References 201 5 Analysis of Accelerated Degradation Data and Reliability Model Development 203 5.1 Introduction 203 5.2 Degradation Models 205 References 231 6 Accelerated Test Planning 233 6.1 Introduction 233 6.2 Issues to Consider Prior to Accelerated Testing 233 6.3 Planning for Accelerated Life Tests 237 6.4 Planning for Accelerated Degradation Tests 246 References 250 7 Accounting for Uncertainties and Model Validation 251 7.1 Introduction 251 7.2 Uncertainties in Evidence 251 7.3 PPoF Model Uncertainties, Errors, and Validation 259 7.4 Applications of Model Validation in ADT 263 References 268 Index 26