Resistance Welding of PAEK / Carbon Fiber Thermoplastic Composite Laminates

Martı, İsmail Baha
The main purpose of this thesis is, as the first time in the literature, to investigate usability of resistance welding joining method for poly(aryletherketone) (PAEK) thermoplastic matrix carbon fiber (CF) reinforced composite laminates (PAEK/CF). For this purpose, effects of six different Interlayer Forms having different stainless steel meshes as Heating Elements and different woven glass fiber forms as Insulating Layers were studied. After determining welding parameters for each specimen group, performance of the resistance welding operations was compared by ultrasonic inspection, microscopic examination, DSC analyses, and by three different interlaminar mechanical tests. Analyses and tests generally revealed that use of stainless steel meshes as Heating Elements could supply proper amperage level for the heating, melting and crystallization stages of the PAEK matrix during welding consolidation. It was also observed that in order to prevent Current Leakage problem to the other layers in the composite laminate, rather thicker and heavier woven glass fiber forms as Insulating Layers should be used. Otherwise, not only voids could form in the thermoplastic matrix, but also delamination might occur in the upper or lower composite laminates being welded.


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Citation Formats
İ. B. Martı, “Resistance Welding of PAEK / Carbon Fiber Thermoplastic Composite Laminates,” M.S. - Master of Science, Middle East Technical University, 2023.