Recently, a novel adhesive which can be dismantled has been developed. The adhesive, so called "dismantlable adhesive", consists of resin and thermally expansive microcapsule. Since the adhesive expands greatly as the temperature increases, joints bonded with it can be peeled off due to internal stress caused in the adhesive layer. In order to investigate the expansion and dismantlability of the adhesive and the joint, we measured the thermal expansion of the adhesive and observed the interface between the adhesive and adherends. In addition, cleavage between the adhesive and glass adherends at high temperature was observed.

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The impact fatigue strength of the acrylic adhesive under impact tensile loading was evaluated by adding impact cyclic loads to a tubular butt joint. The material of adherends was aluminium alloy A5052-H34,and the acrylic adhesive Hardloc M-372-20 was used. First, the combined loading test was performed in order to evaluate the static strength of the adhesive. As a result, the value of fracture stress under shear load is stronger than the value of fracture stress under tensile load. As the adhesive layer thickness become thick, the value of fracture stress become low. In the impact fatigue test, the thickness of the adhesive layer was 0.1mm. As a result, the maximum incidence stress becomes low, the number of impact loads to a fracture will increase. In cace the insident stress is 9MPa, the specimen did't fracture even if it was subjected to the impact loads 1 million times. It was considered that the fatigue limit is 9MPa.

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Diamond films are synthesized on Mo substrate using combustion flame generated from the reaction of the acetylene and oxygen gases. In this case, diamond films are subjected to thermal load due to a mismatch of thermal expansion between diamond films and Mo substrate during cooling process from synthesis temperature to room temperature. Thus, the delamination between the diamond film on Mo substrate occurs due to these thermal stresses. To prevent the delamination, a three-step synthesis method is proposed. One of its advantages is that adherent diamond film on Mo substrate can be obtained by using a interlayer of first synthesis. The delamination between diamond films synthesized using the three-step synthesis method on Mo substrate is discussed.

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Adhesive sheet specimens with different thicknesses were manufactured, by hardening only an acrylic adhesive. Mechanical properties of their sheet specimens were examined by the tension tests. Using these mechanical properties, the deformation behaviour of simple lap joints was analyzed by the finite element method. These analytical results were compared with experimental results. Both didn't agree. It considers from this result that the mechanical properties of the adhesive are changing widely inside the adhesive layer. The acrylic adhesive causes molecular orientation in the adhesive interface neighborhood with metal. In the part which caused molecular orientation, the Young's modulus is low and the deformable quantity is large. Also, a center in the adhesive layer is supposed to have the opposite properties.

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This paper deals with a two-dimensional stress analysis of a butt adhesive joint with rigid fillers in the adhesive subjected to a tensile load. Similar adherends were replaced with finite strips, and an adhesive was replaced with a finite strip including rigid fillers. The analysis was done using the two-dimensional theory of elasticity in order to evaluate the joint strength. The effects of the location and size of rigid fillers on the stress distributions around the fillers and at the interface were shown by numerical calculations. For verification, photoelastic experiments were performed. The analytical result was in fairly good agreement with the experimental result.

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Tensile lap shear tests at various temperature were performed at several crosshead speeds using single-lap joint specimens. In the tensile lap shear tests, it was found that the strength of the adhesive is highly temperature-sensitive. In the present work, the effect of forming temperature on the deformation characteristics of adhesively bonded aluminum sheets was investigated by performing V-bending experiments with various temperature. In order to discuss the effect quantitatively, the numerical simulations for the bending were also conducted using a rate and temperature dependent constitutive model for the adhesive. Consequently, it was found that the large shear deformation and 'gull-wing' bend are suppressed by low temperature forming.

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The adhesive strength of tubular butt-joint under combined axial load and torsion was investigated using a highly ductile acrylic adhesive. Adhesive strength diagrams under combined stresses were determined on the normal-shear stress plane. From the experiment, it was found that shear strength decreases remarkably with increasing normal stress, and furthermore, it is strongly affected by the strain rate since this adhesive has high rate sensitivity in flow stress.

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In assembly lines of cars, very long handling arms consisting of aluminum alloy have been used to position windshields on the bodies. We developed new handing arms on which CFRP plates were bonded adhesively to reinforce their stiffness and to reduce their vibration. In this study, we investigated the influences of the thickness and width of the aluminum alloy adherends in the specimen on the fatigue life. Fatigue tests using four types of the smaller specimens having aluminum adherends of different thickness and width were carried out. Two S-N curves of the four types of the specimens were obtained based on the two stress values at several points far from the edges of the adhesive layer. As the result, we found that the fatigue life was influenced by the thickness of the aluminum alloy and that we had to predict the fatigue lives of the actual structures using stress values of adhesive layers.

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