Detection of Fracture in Structural Adhesive Using RFID Tags

Although structural adhesives are used in many fields, there are few non-destructive evaluation techniques which are economical and widely applicable. In this study, a new non-destructive evaluation technique of structural adhesives using radio frequency identification (RFID) tags was proposed to keep reliability of structures. This method enables us to detect fracture of structural adhesives by the communication situation of RFID tags. Communication properties of two types of RFID tags, the small tags and in-metal tags, were investigated during bending test, and the effects of tags on mechanical properties were evaluated using finite element method. A fracture of epoxy resin was successfully detected by small tags, and in-metal RFID tag makes it possible to detect internal fracture of epoxy resin covered with SUS304. There is little difference of maximum stress with or without tags in stress field, and it was shown that adhesive strength did not decline with the presence of RFID tags. Therefore, it was shown that this proposed method is effective to find a fracture of structural adhesives.