How to obtain the adhesive strength for double lap joint by using single lap joint

6th International Conference on Fracture Fatigue and Wear

Noda, N.A.^1 ; Li, R.^1 ; Sano, Y.^1 ; Takase, Y.^1 ; Takaki, R.^1 ; Miyazaki, T.^2

Department of Mechanical Engineering, Kyushu Institute of Technology, 1-1 Sensui-cho, Tobata-ku, Kitakyushu-shi

804-8550, Japan^1

Department of Mechanical Systems Engineering, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Nakagami-gun, Okinawa

903-0213, Japan^2

关键词: Adherend thickness;    Adhesive strength;    Double lap joint;    Equivalent condition;    Intensity of singular stress;    Japanese industrial standards;    Single lap joints;    Specimen geometry;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/843/1/012006/pdf
DOI  :  10.1088/1742-6596/843/1/012006

来源: IOP

【 摘 要 】

The testing method of adhesive strength of lap joint is prescribed in Japanese Industrial Standard (JIS K6850). However, it has been reported that the strength of double lap joint (DLJ) is about two times larger than the one of single lap joint (SLJ). Therefore, suitable testing method has been required from industries. In this study, the equivalent conditions of strength for SLJ and DLJ are investigated in terms of the intensity of singular stress field (ISSF) appearing at the interface end. First, in order to minimize the bend effect for SLJ, the effect of the specimen geometry on ISSF and deformation angle at the interface corner is considered under the same adhesive geometry and load P. It is found that the minimum ISSF of SLJ can be obtained when the adherend thickness t1is large enough, and the deformation angle at interface corner is also smallest when adherend thickness t1is large enough. Therefore, it is necessary to use the specimen with thicker adherend thickness. Then, the equivalent conditions of strength for SLJ and DLJ is investigated by changing adherend thickness. The results show that the strength of the DLJ in JIS ( t1= 1.5mm) can be obtained by using the SLJ with adherend thickness t1= 7mm. When the adherend thickness t1≥ 25mm, the strength of SLJ is nearly equal to that of DLJ.