Strength Evaluation for Dissimilar Adhesive Shaft Joints Subjected to Impact Tensile Load

摘要

The impact strength was evaluated for a butt adhesive shaft joint of Al alloy and PMMA materials. The materials were bonded together by cold-setting epoxy, commercial base adhesive. An impact tension test was carried out using a drop-weight testing machine. The fracture initiation time in the adhesive interface was determined from the measured strain gage signal. In order to establish the method of strength evaluation, the impact tensile strengths of the adhesive joints were evaluated by the stress singularity field parameter and the average fracture stress. Fracture toughness in the dynamic stress field was determined from the stress distribution in the vicinity of the edge of the adhesive interface calculated by the finite element method at the fracture initiation time. The static fracture toughness was also determined by a similar method using the same type of specimen used in the dynamic test. It was found that the dynamic strengths exhibited considerably larger values than the static strengths Furthermore, the dynamic strengths were evaluated for the butt adhesive shaft joints of Al and Al alloys, and also PMMA and PMMA materials, in order to confirm the reliability of the measurement, the location of fracture and the stress distribution in the vicinity of the adhesive interface were investigated in detail.