Resistance Welding Joints of <scp>CF</scp>/<scp>PEEK</scp> Orthogonal Laminates Strengthened by in situ Grafting of <scp>ZnO</scp>‐Nanowires: Preparation, Properties, and Mechanism

ABSTRACT A high strength bonding interface by resistance welding has always been a goal for the production of highly reliable resin‐based composite joints. In this work, SS mesh element with grafted ZnO nanowires (SSM@ZnO) was developed for resistance welding of CF/PEEK composite laminates to improving interfacial strength. First, the surface of stainless‐steel mesh (SSM) was modified by in Situ grafting of zinc oxide (ZnO) nanowires via hydrothermal growth method and the as‐obtained product (SSM@ZnO) used to the resistance welding of carbon fiber/polyether ether ketone (CF/PEEK) orthogonal laminates. The dependance of the SSM@ZnO microstructure, heating properties, wettability and interfacial adhesion on the growth time was investigated. The electrical heating rate under constant input power is increased from 4.8°C/s to 7.12°C/s, and IFSS between SSM@ZnO and PEEK resin is increased from original 45 MPa to 61 MPa. The mechanical properties and failure mode of CF/PEEK resistance welding joints were characterized by single lap shear stress (SLSS) and SEM, respectively. At SSM@ZnO growth time of 8 h, the SLSS reaches the maximum value of 52.8 MPa, and the failure mode was shifted from interfacial peeling between CF/PEEK laminate and adhesion layer to fiber tearing of CF/PEEK laminate surface.