Issue 49

A. En-najiet alii, Frattura ed Integrità Strutturale, 49 (2019) 748-762; DOI: 10.3221/IGF-ESIS.49.67 750 The tensile specimens, illustrated in Fig.1, were prepared according to the ASTM Standard D638-03 [14] method of tests for the tensile properties of plastics. Figure 1: Dimensions of specimens according to ASTM D638-03[14]. Symbol Description Size (mm) L 0 Total lengh 75 D Initial distance between jaws 42 L Lengh of the calibrated part 25 G Lenth between landmarks 20 W With of the calibrated 4 R Small radius of curvature 8 W0 Widths at the ends 14 B thikness 2 Table 1: The dimensions of dumbbell specimen for tensile test. Fig.2 illustrates the evolution of the stress applied to the specimens (MPa) as a function of the deformation, ℇ (%). The general appearance of this curve exhibits ductile behavior. Figure 2: Tensile stress-Deformation curvedumbbell specimen. It can be observed from Fig. 2 that the curve includes four zones, each of which reveals a particular mechanical behavior of the material (ABS) during the tensile test. Zone 1 (linear): this is the reversible elastic deformation of the material owing to the amorphous phase.