Prediction of the notched strength of woven-ply PolyPhenylene Sulfide thermoplastic composites at a constant high temperature by a physically-based model

A simple physically-based model - the Critical Damage Growth model - derived from fracture mechanics criteria has been applied to quasi-isotropic carbon fibers woven-ply reinforced PolyPhenylene Sulfide (PPS) laminates to predict their notched strength under constant high temperature conditions. The tested notched specimens are characterized by an elastic-brittle response resulting from transverse matrix cracking and fiber breakage near the notch tip. This model requires only, as input parameters, the unnotched strength and fracture toughness of the laminate determined from the measurements of critical strain energy release rates. The translaminar fracture toughness has been calculated by means of the compliance method applied to quasi-isotropic Single-Edge Notch specimens with different initial crack lengths. For various hole diameters, the capabilities of the Critical Damage Growth model are very good to predict the notched strength of quasi-isotropic C/PPS laminates tested at a temperature higher than glass transition temperature when PPS matrix ductility and toughness are exacerbated.