PSI - Issue 42

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Ayse Cagla Balaban et al. / Procedia Structural Integrity 42 (2022) 284–291 Ayse Cagla Balaban et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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Table 2. The mechanical properties of PVC Foam

Elasticity Modulus (MPa)

Shear Modulus (MPa)

Poisson Ratio

PVC Foam

56

0.11

23

The resin used in this study comprises epoxy resin (XB 3585 Resin with a density of 1.15 g/cm 3 ) and hardener (Aradur 3486 CH with a density of 0.95 g/cm 3 ) for a resin-hardener ratio of a 100:32 by weight. The sandwich composite plate was cured at room temperature for five days and post-cured at 85 ℃ for 8 h ours. Dimensions of the sandwich composite material can be seen in Figure 1 (a) and Figure (b) shows the schematic illustration of the manufactured sandwich composite.

Fig. 1. (a) Dimensions of the sandwich composite; (b) Manufactured sandwich composite

3. Experimental Testing It is important to examine all possible failure modes depending on the application areas as they can cause catastrophic failure within the material. The sandwich panel is dependent on the local failure types and cohesion of the facesheets that can propagate to the global failure modes. Sandwich flatwise tension, sandwich flatwise compression, sandwich edgewise compression and core flatwise compression tests were completed. All the experiments have been performed in a universal testing machine (Shimadzu AG-100). 3.1 Sandwich Flatwise Tension Test The sandwich composite may buckle inward or outward depending on the facesheet facing sides and flatwise tension and compression strengths of the bond between the facesheets and core. If the bond between facesheets and core material is strong, the tension failure happens in the core. The sandwich material is subjected to uniaxial tensile force from the plane of upper side of the sandwich. In this experiment, three specimens were tested according to ASTM C297/ C297M-04 standards in order to determine the flatwise tensile strength of the material. The dimensions of the test specimens can be seen in Figure 2 (a) and experimental set-up can be seen in Figure 2 (b). Each specimen has been located at the center of the loading plate and test speed was chosen as 0.5 mm/min according to ASTM standards.