Role of the surface quality on the mechanical behavior of CFRP bolted composite joints

Abstract

International audienceIn this research paper, the influence of two drilling processes on the mechanical behavior of bolted composite joints was investigated. Two stacking sequences were studied namely, [\textpm45°]2S and [90/+45/0/-45]S. The composite specimens were drilled using conventional machining (CM) and abrasive water-jet machining (AWJM). Fatigue tests combined with infrared thermography (IR) were used to determine the high cycle fatigue strength and monitor damage accumulation and heat dissipation. Fatigue test results at 65% of the ultimate tensile strength showed that the damage for [\textpm45°]2S and [90/+45/0/-45]S bolted joints drilled with CM were 65% and 54% respectively. However, when the AWJM was used, the damage accumulated was 25% more compared to CM. This difference was confirmed by IR results which showed that [\textpm45°]2S bolted joints drilled with CM dissipate 23% more heat than those drilled with AWJM. The current study demonstrated that AWJM extends the high cycle fatigue strength and the fatigue life of bolted composite joints