PSI - Issue 33

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Giacomo Risitano et al. / Procedia Structural Integrity 33 (2021) 748–756 Risitano et al./ Structural Integrity Procedia 00 (2019) 000–000

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Fig. 4. Temperature trend vs. applied stress during a static tensile test at 400 MPa/min

Considering a stress rate of 800 MPa/min (Fig. 5), the energetic release is faster than the previous two cases and it is difficult to distinguish in a clear way the two different temperature phases, however it is possible to make the intersection of the temperature regression line for Phase I and Phase II. The value of the limit stress found on the three tests, at 800 MPa/min is equals to 220.2±7.4 MPa; a value almost near to the one obtained for 400 MPa/min. It is important to observe how the limit stress has been obtained by means of a simple static traction test and in a very short amount of time (~5 minutes per test).

Fig. 5. Temperature trend vs. applied stress during a static tensile test at 800 MPa/min