Experimental investigation into the effects of changing the variouscurve radiuses of composite laminar & angle between tool axisand normal vector of the surface on induced delamination indrilling Woven-GFRP

The usage of composites in the aerospace industry particularly in structures that are composed of numerous workpieces, has extensively increased. Drilling is considered as a critical process in the composites assembly process and any defects causes toreject of parts leading to increasing cost of production process. Delamination phenomenon or composites delaminate, is the most important defects that may occur during the drilling of the composites. The airplanes fuselage and wings exist pieces ofcomposite contain different curves and arcs that usually require to perform drilling with different angles on them. This paper considers delamination phenomenon during drilling in composites curved laminates. For these purposes, the radius of thecutting force affected zone caused by the drilling process was numerically calculated by ANSYS finite element package resulting in design and manufacturing of a modular jig and fixture. Holes created by different angels to surface normal vectoron composite laminates with different curves in 2 situations: convex and concave, and finally the holes in the polarized light imaging and results obtained were compared with each other.

Keywords:

Drilling , Delamination , Glass Fiber Reinforced Plastics (GFRP) , Composite Laminate , Concave -Convex Composite Laminate , normal vector of the surface