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The main purpose of this paper is defining a procedure that allows the tracking of the measuring point in notched specimens under static testing, investigated by full field experimental methodologies. One of the main problems is the motion of the measuring zone, associated with its compliance under increasing load. A procedure based on Digital Image Correlation (D.I.C.) aiming to define the stress concentration factor in a dynamic way has been developed. Furthermore, numerous revealing tests based on Thermographic Analysis (T.A.) have been carried out on flat plastics specimens with different hole diameters. The assessed and final tracking procedure could be used to better define the trend of temperature changes during the static tensile test, as well as measuring the stress concentration factors in notched specimens. [ABSTRACT FROM AUTHOR]

Abstract: Following previous results showing that under static loads it is possible to detect the first plasticization of the specimens at the end of the thermoelastic phase, the authors have conducted experimental trials to verify that this effect can be pointed out in notched and unnotched polyvinyl chloride (PVC) specimens. The goal is to define the real elastic phase also for materials for which the elastic limit and the yield stress are not easily defined, different from the case of steel. The results show a variable thermal behaviour depending on the distance from the notch. The thermal behaviour, proportional to the stress in the totally elastic phase, accordingly with the thermoelastic effect, deviating from the linearity, points out the beginning of the local plasticization. The thermoelastic limit, moving from the notch edge to the specimen boundary, allows to follow the paths of plasticization. The results are also compared with those found by cyclic loading using the thermographic methodology already verified by the authors and other researchers. [Copyright &y& Elsevier]