Hygrothermomechanical Evaluation of Transverse Filament Tape Epoxy/Polyester Fiberglass Composites

Influence of Quick Ageing on the Fatigue Behaviour of SMC Composite Materials

“…• Static tensile and compressive strengths of TFT/epoxy and TFT/polyester composites with different lay-ups [7] had been found to be almost insensitive to elevated temperature and moisture (500 h • For GFRP, CFRP and KFRP laminates, it has been reported in Reference [8] that the matrix and interface-dominated properties, such as the 45°static strength and the interlaminar shear strength, increased for material exposed to 65% R.H. with respect to dried material. Moreover for 0°/90°GFRP laminates, being almost constant the static strength, a slight reduction of the tensile modulus was noticed for moisture exposed laminates with respect to those dried.…”

“…• An improvement of the high cycle tensile fatigue properties was found by Carisella et al [6] for moisture saturated specimens of glass reinforced epoxy and polyester laminates with respect to dried laminates. • Tensile fatigue tests on TFT/epoxy composites [7] laminates subjected to the same conditionings [9] and they reported the almost complete insensitivity of the tensile fatigue of [0/90] laminates to the hygrothermal ageing treatment. • Finally, in Reference [11], the influence of 2.5 years of weather conditioning and exposure at 60°C and 84% R.H. on the tensile fatigue behaviour of notched [±45/0 3 /±45/0] s carbon/epoxy laminates was investigated.…”

“…It would remain to analyse whether these conditionings correctly simulate the actual effects of the environment on the mechanical properties of the SMC under investigation: a brief comparison with the environmental conditioning reported in other research on the same matter [4][5][6][7][8][9][10][11][12] showed, in fact, that their duration is quite reduced. In the authors' opinion, they are sufficiently representative of the in-service condition, at least for automotive components because the aim of the quick ageing is not to reach the saturation condition, for instance of moisture, but rather to reproduce the change in environment condition at which the components could be exposed.…”

“…• Static tensile and compressive strengths of TFT/epoxy and TFT/polyester composites with different lay-ups [7] had been found to be almost insensitive to elevated temperature and moisture (500 h to about 50°C and 98% R.H.); nevertheless, for the TFT/polyester composite, a longer exposure (about 4000 h) to the same environment caused a significant loss of strength (about 40%). • For GFRP, CFRP and KFRP laminates, it has been reported in Reference [8] that the matrix and interface-dominated properties, such as the 45°static strength and the interlaminar shear strength, increased for material exposed to 65% R.H. with respect to dried material.…”

“…• An improvement of the high cycle tensile fatigue properties was found by Carisella et al[6] for moisture saturated specimens of glass reinforced epoxy and polyester laminates with respect to dried laminates. • Tensile fatigue tests on TFT/epoxy composites[7] treated for 500 h to about 50°C and 98% R.H. evidenced no influence of moisture and temperature on the long life fatigue strength. • A comparison of dried, 65% R.H. moisture saturated and boiled glass/epoxy laminates [8], showed a slight increase in the high cycle fatigue properties for boiled [0/90] laminates, being almost similar and lower the properties for the other conditionings; for [±45] laminates instead, the fatigue strength of the boiled material was slightly reduced.…”