TY - JOUR A1 - Zerbst, Uwe A1 - Madia, Mauro A1 - Klinger, Christian A1 - Bettge, Dirk A1 - Murakami, Y. T1 - Defects as a root cause of fatigue failure of metallic components. I: Basic aspects T2 - Engineering Failure Analysis N2 - According to the definition of the ASM handbook [1,3], a defect is "an imperfection. that can be shown to cause failure by a quantitative analysis and that would not have occurred in the absence of the imperfection". The topic of the present three-part review is a discussion of defects which can cause failure in cyclically loaded structures. The features discussed comprise material defects such as non-metallic inclusions, pores or micro-shrinkages, etc. and geometric defects such as surface roughness and secondary notches which have their origin in manufacturing, and defects such as surface damage due to scratches, impact events or contact fatigue as well as corrosion pits which arise in service. In this first part, the discussion is prefaced by an introduction to basic aspects which are essential for a deeper understanding of the characteristics and mechanisms how the defects influence fatigue crack initiation and propagation. These include the life cycle of a fatigue crack from initiation up to fracture, crack arrest, multiple crack initiation and coalescence, and the material and geometrical properties affecting these. PB - Pergamon-Elsevier Science Ltd CY - Oxford, England KW - Defects KW - Fatigue crack propagation stages KW - Crack arrest KW - Multiple cracks PY - 2019 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/47372 AN - OPUS4-47372 SN - 1350-6307 VL - 97 SP - 777 EP - 792 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany