PSI - Issue 24

Michele Perrella et al. / Procedia Structural Integrity 24 (2019) 601–611 Perrella et al. / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 1. Schematic of mold: 1) lower plate; 2) – 3) mold cavity assembly; 4) upper plate; 5) alignment pins.

2.1. Experimental set-up Creep tests were performed by using an in house designed and realized testing system (Fig. 2). The specimen is clamped with grips that are allowed to move only along the loading direction by two linear guides. The clamping system is mounted on a steel frame, which is located inside a thermally insulated chamber. Each grip end is provided with a spherical bearing in order to minimize eccentric loading of the specimen. A thermostat controlled heater is used for imposing the selected temperature field, whilst the stress field rate is applied by a dead-weight load.

a

b

Fig. 2. Experimental layout for static (a) and creep tests (b).

In this work, tensile creep tests were carried out imposing the boundary conditions reported in Table 4 over a duration of about 6 days each. Isothermal creep curves were shifted in order to obtain master curves according to the