The interface stress distributions in band scarf adhesive joints with similar and dissimilar adherends under static bending moments are analyzed using three-dimensional finite element calculations. It is found that the maximum principal stress decreases as Young's modulus ratio E1/E2 between the dissimilar adherends decreases, as the adhesive Young's modulus increases, as the adhesive thickness increases, and as the number of bonded interface parts decreases. The number N is optimal as N=2. It is observed that the maximum principal stress is minimal when the scarf angle θis around 60˚, therefore　the　joint　strength　of　band　scarf　adhesive　is assumed　to　be　maximal　for　scarf　angle　of　60˚. The　maximum　principal　stress　in　the　joint　with　two interface　bonded　parts　subjected　to　linear　stress distributed　to　partial　region　is　smaller　than　that distributed　to　the　whole　region.　The　strength　of the band　scarf　adhesive　joint　with　the　30%　reduced interface　bonded　area　is　approximately　the　same　asthat　with　the　completely　bonded　area　at　the interfaces. The strains in the adherends and the joint strengths were measured in the experiments. The measured strains and joint strengths are in fairly good agreement with those obtained from 3-D FEM calculations.

In acrylic silicone (M-CAS) solution containing active methylene group, silica micro particles were synthesized by addition of tetraethoxysilane. When this composite film coated on a glass substrate, the water contact angle showed 120°. Furthermore, the film which the hexamethyldisilazane as silane coupling agent was added to together, showed the contact angle of 155°. However, as a result of the wear test, the contact angle of the composite film reduced to 60°. When the crosslinking agent was added in reaction solution and was cured by UV irradiation, contact angle of the coating film showed 130°. Even through wear test, the UV-irradiation-curing composite film maintained its contact angle ca.100°. Repeated coating and UV irradiation-curing formed the super water-repellent film, and even through wear test it maintained excellent water-repellency, its contact angle being reduced only to 130°.

The effect of bending stiffness of adherends on the strength of adhesively bonded single lap joints is investigated experimentally. The joints are bonded with an epoxy resin adhesive. The material of adherends are aluminum alloy A2017 and stainless steel SUS304 which are popular metals for the exterior material of industrial products. The adhesive surface of the adherend is unprocessed with primers in this paper. Therefor, surface roughness and wetting tension of adhesive surfaces are constant for each adherend material. The thickness of the adherend is adjusted by a shaper to control the bending stiffness value of the adherend. The experimental results exhibits that the effect of bending stiffness on the strength of lap joints is extremely large. The bending stiffness of adherends is the most influential factor to change the strength of the lap joint even using different types of material for the adherends.