Experimental investigation of mode I fracture energy of adhesively bonded joints under impact loading conditions

Background Recently, the automotive industry has paid attention to multi-material structures to reduce CO2 emission. Hence, the use of light-weight and high-strength materials such as Al–Mg alloys, high-tensile-strength steel and carbon-fiber-reinforced plastics (CFRP) is essential to lighten the vehicle weight [1]. Joining methods for these dissimilar materials are the key to apply them into the structural part of the vehicles in combination. When the CFRP is jointed with other materials, welding, which is one of the most standard joining methods for vehicles, cannot be applied, and other methods must be considered. When dissimilar materials are jointed, thermal deformation at the joints often becomes a problem because of the difference in thermal coefficient of expansion, and reduction methods must be considered. Adhesive bonding can be applied to the joint among various types of materials to overcome these issues, as well as absorb vibration, prevent electrolytic corrosion, seal clearances, etc. Therefore, adhesive bonding can be one of the leading joining methods for the structural part of vehicles. Abstract