Study on microstructures and mechanical performance of laser transmission welding of poly-ether-ether-ketone (PEEK) and carbon fiber reinforced PEEK (CFR-PEEK)

The reliable assembly of poly-ether-ether-ketone (PEEK) and carbon fiber-reinforced PEEK (CFR-PEEK) is crucial to effective load transfer within lightweight high-stiffness structures, which are commonly demanded in aeronautical, automobile, medical industries. In this work, laser transmission welding CFR-PEEK has been performed by using a 1070 nm Nd:YAG fiber laser. effects process parameters including power, scanning speed, clamping pressure on joining quality have investigated via mechanical, morphological, thermal characterization. Results show that strong bonds formed entanglements polymer chains at the interface mechanical embedment between fibers PEEK. formation mechanisms bubble defects classified into three types. One them was eliminated joints twice, significantly improved joints' performance hermeticity with maximum strength reaching 11.6 MPa. Also, comparative study PEEK/PEEK PEEK/CFR-PEEK shows existence increased decomposition threshold, region, due their great conductivity. Besides, influence crystallinity analyzed, then from 11.7% 34.1% through annealing.