In resin-metal composite structures such as electronic products with the epoxy resin molding insulator, a thermal fatigue of the epoxy resin during thermal cycles is a critical issue. Since a thermal stress in the epoxy resin and its strength change simultaneously during thermal cycles, an estimation method for the thermal fatigue reliability in consideration of the temperature dependence of fatigue strength is required. In this paper, the technique of predicting thermal fatigue crack growth rate in epoxy resin is studied and we proposed an estimation method using strain intensity factor K/E as an evaluation parameter. In order to evaluate the proposed method, both the crack propagation test by thermal cycles and the thermal stress evaluation by viscoelastic FEM analysis were carried out. As a result, it was found that the proposed method estimated the crack growth rate under thermal fatigue test less than that of iso-thermal fatigue test.
|Number of pages||8|
|Journal||Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A|
|Publication status||Published - Jan 1 2010|
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering