Hole cold expansion is a technique widelyused to improve the fatigue life of components withholes, e.g. bolted or riveted joints. As it has been demonstratedin literature by analytical, numerical and experimentalanalyses carried out by several authors, thecompressive residual stresses introduced by the hole coldexpansion have a beneficial influence on both the staticand the fatigue strength of the treated component, becausethey reduce significantly the typical stress peaksaround the hole due to stress concentration. In the literature,various analyses of the residual stresses introducedby the hole cold expansion have been performed byusing several methods such as X-ray diffraction, neutrondiffraction and the modified Sachs method. Unfortunately,all these method are affected by some limitations: lowmeasurement depth (X-ray method), complex measurementprocedure (neutron diffraction method) and approximateformulation (Sachs method). In order to overcomesuch drawbacks, in this study a new mechanical method,based on an innovative extension of the “rectilineargroove method” associated with the classical “integralmethod” calculation procedure, is proposed. Experimentalassessment of the proposed method has been performedby using aluminum 5083 H321 specimens with holessubjected to various levels of cold expansion.
|Numero di pagine||14|
|Stato di pubblicazione||Published - 2012|
All Science Journal Classification (ASJC) codes