Recently, the light weight and the safety of automobile are the important targets of automotive design and the parts for car have been substituted the plastic or the porous material for the steel material. As the aluminium foam has many pores at its surface, it has the fatigue property of bonded face which differs from general material. In this study, two dimensional model is designed and performed with the fatigue analysis as the variable(θ value) becomes the slant angle of bonded face at the specimen with the aluminium foam. As the analysis result on the models with the slant angles of 6°, 8° and 10°, the bonding forces are disappeared when the fatigue loads are repeated during 4000 cycle, 4500cycle and 5000cycle respectively. By comparing with the analysis results of three models, the fatigue cycle to endure fatigue load becomes larger as the slant bonded angle becomes higher. So, the structural safety can be seen by applying only as only a simulation of finite element method instead of the experiment where much cost and time is spent. In this study, the configuration of aluminum foam is designed with the shape of TDCB Mode II. The shear fatigue strength of the bonded structure can be evaluated by the analysis program of ANSYS.
In this study, the specimen of tapered double cantilever beam(TDCB) with aluminum foam is designed and shearing fatigue strength is based on the investigation of static behaviour analysis under the condition of mode Ⅱ. These specimen models have length and width of 200 mm and 25 mm. The inclined angles of adhesive face at the specimens are 6°, 8 °and 10°. As the inclined angle becomes higher, the time for which the model can not be broken during fatigue load becomes longer. The shearing strength of TDCB bonded structure with aluminum foam applied by shearing fatigue load can be evaluated through finite element method.
four kinds of models designed by the basis of British industrial standard and ISO international standard in this study. Energy release rates at mode 1 are investigated by the fatigue analysis of aluminum foam TDCB model bonded with adhesive. These analysis models are compared each other by classifying four models into m values with 2, 2.5, 3 and 3.5. The value of m as the gradient of model is represented with the function of crack length(a) and height of model(h). Through the correlation relation, the fracture behavior of bonded material is analyzed and these analysis results can be applied to composite structures of various areas. Mechanical property and fracture toughness of composite material are also analyzed in this study.
Aluminum foam with porous material has the excellent mechanical property of light weight and impact absorption. It is necessary to obtain the information of fracture toughness at the adhesive work by the joint method. This study is investigated by fatigue analysis with DCB(Double Cantilever Beam) specimen models to evaluate the strengths at adhesive joints on the basis of British industrial and ISO international standards. 4 kinds of specimens are modelled by changing the height of specimen and the analysis results are compared with each other. As the height of specimen becomes lower, the displacement on the y direction, load and energy release rates become higher. Through the correlation obtained by this study result, fracture behaviors are examined and mechanical properties can be understood. Aluminum foam material bonded with adhesive can applied to the real composite structure by use of this study result.
선박을 운항하는 항해사의 피로도(Fatigue)는 안전항해와 매우 밀접한 관계를 가지고 있다. 또한, 당직항해사의 피로는 중대한 해양사고를 초래할 수 있다. 본 연구에서는 항해사의 근무환경, 피로유발요인 및 피로증세 등에 대하여 문헌조사를 실시하였다. 그리고 실습항해사를 대상으로 졸음, 정신적 육체적 작업부하도에 대한 피로도 관련 설문조사를 실시하고 그 결과를 분석하였다. 마지막으로 이와 같은 피로도 조사 및 설문조사 분석결과를 바탕으로 항해사의 피로도 분석항목을 선정하고 이를 기반으로 향후 항해사의 업무수행능력을 평가하기 위한 피로도 분석모델을 제안하였다.