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• The residual tensile strength after impact of glass/polyester laminates is investigated. • Damage areas are detected by using visually inspection. • Residual tensile strength of samples impacted by hemispherical tip is estimated using two fracture mechanics models. • The residual tensile strength for the damaged laminates is predicted using new model. • The proposed model predicts the residual strength with much higher accuracy and much less error than the existing models. In this study, the residual strength of the post impacted glass/polyester laminates is investigated by the conduction of tension after impact (TAI) loading. The specimens are placed on a rigid plane and subjected to low velocity impact using a drop weight impact tower. Damage areas are detected by using visually inspection and measuring the size of the permanent impression on the surface of specimens. The relationships between the impact energy and degradation of mechanical properties have been stablished for the composites. The residual tensile strength for the impact-damaged laminates is predicted using new model. The correlation between the experimental and new model results is found to be good. Two models proposed by Caprino and Koo have been using to compare the results. [ABSTRACT FROM AUTHOR]

Glass-fiber-reinforced aluminum layers (GLARE) are one of the excellent impact resistant materials, benefited from both the metal and glass fibers properties. Owing to their high impact damping properties, the shape memory alloys have been also considered as useful materials for arming the conventional impact-exposed materials. In the present paper, the shape memory wires were integrated with GLARE laminate and its response to the Charpy low-velocity impact was experimentally studied. The current study is aimed to determine the effects of three parameters (pre-strain percentage of shape memory alloy (SMA), glass fibers angle and the location of SMA wires within the novel fiber metal laminate) for the first time. Hybrid GLARE specimens of this study were planned by Taguchi design of experiments (DOE) method and contained Nitinol shape memory alloy wires. The results showed that the pre-strain and the angle of glass fibers are the most effective parameters on the impact energy absorption at accepted levels of confidence. Regarding the innovations in the construction of this type of impact-resistant hybrid composites, this study could be used in design of aerospace bodies. [ABSTRACT FROM AUTHOR]

The aim of this research is to investigate the thickness influence on the efficiency of multiwalled carbon nanotubes (MWCNTs) in glass/epoxy composite laminates under the high‐velocity impact. Combining 0.25 wt% of MWCNTs in the 4‐layer and 8‐layer specimens and 0.1 wt% of MWCNTs in the 16‐layer specimen led to the maximum rise in the energy absorption and specific perforation energy compared with the unreinforced laminates. The significant growth in energy absorption in the 4‐layer, 8‐layer, and 16‐layer specimens was 5.8, 8.3, and 14.4 J, respectively. The number of agglomerations (dislocations) in the matrix was consequently increased as a function of thickness, which led to the better performance of MWCNTs with lower weight percentages in the composite laminates containing more layers. The scanning electron microscope was used to observe the dispersion and agglomeration of MWCNTs in the resin epoxy, and there was also an improvement in the fiber–resin bonding. [ABSTRACT FROM AUTHOR]