The measurement method of the crack growth rate for an adhesive layer under impact load was evaluated by adding impact load to a tubular butt joint. The material of adherends used was aluminum alloy A5052-H34, and the acrylic bonded Hardloc M-372-20 was used as the adhesive. In this experiment we conducted measurements of stresses by observing the stress wave pattern, where the specimens are subjected to two different kinds of impact loads, one under the free-fall impact of the striker and another is under accelerated striker using compressed air. By accelerating the striker using compressed air, only the first wave of the stress wave can be measured. In addition, the crack growth rate was about 7mm/μs. From the above result, it can be concluded that we can obtain the stress value when a crack occurs under the impact loading test.
