دورية أكاديمية

Controlling fatigue crack paths for crack surface marking and growth investigations

التفاصيل البيبلوغرافية
العنوان: Controlling fatigue crack paths for crack surface marking and growth investigations
المؤلفون: S. Barter, P. White, M. Burchill
المصدر: Frattura ed Integrità Strutturale, Vol 10, Iss 35 (2015)
بيانات النشر: Gruppo Italiano Frattura, 2015.
سنة النشر: 2015
المجموعة: LCC:Mechanical engineering and machinery
LCC:Structural engineering (General)
مصطلحات موضوعية: Fatigue crack growth, Crack closure, Crack paths, Mechanical engineering and machinery, TJ1-1570, Structural engineering (General), TA630-695
الوصف: While it is well known that fatigue crack growth in metals that display confined slip, such as high strength aluminium alloys, develop crack paths that are responsive to the loading direction and the local microstructural orientation, it is less well known that such paths are also responsive to the loading history. In these materials, certain loading sequences can produce highly directional slip bands ahead of the crack tip and by adjusting the sequence of loads, distinct fracture surface features or progression marks, even at very small crack depths can result. Investigating the path a crack selects in fatigue testing when particular combinations of constant and variable amplitude load sequences are applied is providing insight into crack growth. Further, it is possible to design load sequences that allow very small amounts of crack growth to be measured, at very small crack sizes, well below the conventional crack growth threshold in the aluminium alloy discussed here. This paper reports on observations of the crack path phenomenon and a novel test loading method for measuring crack growth rates for very small crack depths in aluminium alloy 7050-T7451 (an important aircraft primary structural material). The aim of this work was to firstly generate short- crack constant amplitude growth data and secondly, through the careful manipulation of the applied loading, to achieve a greater understanding of the mechanisms of fatigue crack growth in the material being investigated. A particular focus of this work is the identification of the possible sources of crack growth retardation and closure in these small cracks. Interpreting these results suggests a possible mechanism for why small fatigue crack growth through this material under variable amplitude loading is faster than predicted from models based on constant amplitude data alone.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 1971-8993
Relation: https://www.fracturae.com/index.php/fis/article/view/1637; https://doaj.org/toc/1971-8993
DOI: 10.3221/IGF-ESIS.35.16
URL الوصول: https://doaj.org/article/4c600bd465394d149fe083b13acafdd2
رقم الأكسشن: edsdoj.4c600bd465394d149fe083b13acafdd2
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:19718993
DOI:10.3221/IGF-ESIS.35.16