Impact Damage Tolerance of a Carbon Fibre Composite Laminate.

An investigation was carried out, under the auspices of GARTEUR, at four European aerospace research establishments as the first phase of a collaborative research programme on impact damage tolerance of composite materials. Laminates, from a common batch of material having a 0 90 - 45 0 s lay up, were impacted by dropweight and residual strengths were measured under fully reversed loading for specimens containing barely visible impact damage. The impact damage significantly reduced the static compressive strength but subsequent fatigue loading produced little further reduction in strength and the fatigue strength at 10 to the 6th power cycles was similar to that for non impacted specimens. All four establishments produced similar results and in Phase 2 they will study in more detail a wider range of materials and test parameters. Keywords Carbon fibre, Composite material, Impact, Fatigue, Residual strength, Barely visible impact damage.