Mechanical and microstructural characterization of AZ31 magnesium - carbon fi ber reinforced polymer joint obtained by friction stir interlocking technique

Friction Stir Interlocking (FSI) has been applied for joining dissimilar materials with different physical, chemical and mechanical properties. The FSI process combines friction stir welding with mechanical interlocking where two dissimilar sheets are joined in a lap configuration using a third body interlock. In the present study, AZ31 magnesium alloy and carbon fiber reinforced polymer (CFRP) sheets with a thermoplastic matrix were lap joined through FSI with AZ31 interlocks. Microstructural characterization of the FSI joint showed that AZ31 magnesium sheet was mixed sufficiently with AZ31 interlocks, effectively joining CFRP to the AZ31 sheet. Lap shear tensile testing showed that the load capacity of FSI joints ranged from similar to 80-100 N/mm with fracture occurring within the CFRP around AZ31 interlocks. Finite element analysis was conducted to simulate the lap shear tensile testing for different FSI configurations. The simulation results are in good agreements with the experimental data and observations in terms of both load-displacement curve and CFRP fracture occurring path. (C) 2020 The Authors. Published by Elsevier Ltd.

Automated summary

Friction Stir Interlocking (FSI) is a process used for joining dissimilar materials with different properties by combining friction stir welding with mechanical interlocking using a third body interlock. Through microstructural characterization and lap shear tensile testing, it was found that FSI joints effectively joined carbon fiber reinforced polymer and AZ31 magnesium alloy sheets. Finite element analysis was conducted to simulate different FSI configurations, with simulation results showing good agreements with experimental data in terms of load-displacement curves and fracture paths of CFRP.