Low-velocity impact in a thermoplastic composite at elevated temperature

Abstract

The objective of experimentally exploring the damage tolerance of a thermoplastic matrix composite due to low-velocity non-penetrating impact at 180°F has been achieved. While the impacting of the thinner laminates (9 and 27 plies) was governed by 0.1 inch deep indentation, the thicker laminates (47, 73 and 96 plies) were impacted with 100 ft-lb energy at 16 ftlsec impactor velocity. The effect has been determined of two layups (40150110 and 60130110) and five laminate thicknesses (9 to 96 plies) on these three quantities: indentation depths, damaged areas and post-impact compressive strengths. Effect of the layups on the three quantities was found to be as follows: the 60130110 layup versus the 40/50110 layup produced 1) consistently deeper indentations for all laminate thicknesses and 2) greater damaged areas for all except the 96-ply laminates, but 3) its effect on the post-impact compressive strength was mixed. The effect of laminate thickness on indentation depth was found to be mixed for increasing laminate thickness, the indentation depths of the thinner laminates were increasing whereas those of the thicker laminates were decreasing. This applies to both layups. Damaged area and post-impact compressive strength were found to be increasing functions of the laminate thickness except for the 60130110 layup's 96-ply laminate whose damaged area decreased as compared to the 73-ply laminate.