Papers by Keyword: Side-Crack

Abstract: In this paper, the vibration characteristics of the cantilever rectangular plate with side crack are studied in the way of analysis, which including natural frequency and mode shape. The influences of different parameters of crack, such as the locations and lengths of crack, to the vibration characteristics of the cantilever rectangular plate are investigated. The modal function of the crack plate consists two parts, which are (1) the modal function of intact cantilever rectangular plate from beam functions combination method and (2) corner functions presenting the discontinuity of displacement and slope along the crack. The natural frequencies and modal shapes can be obtained when taking the modal function into the method of Ritz. At last, the effects of the crack location and crack length on the vibration characteristics are investigated, and it could provide the theoretical basis for engineering application and the relevant study.

Abstract: The effect of warm rolling under various conditions on the microstructure and mechanical property was investigated using an AZ31 Mg alloy sheet. Several processing parameters such as initial thickness, thickness reduction by a single pass rolling, rolling temperature, roll speed, and roll temperature were varied to elicit an optimum condition for the warm rolling process of AZ31 Mg alloy. Microstructure and mechanical properties were measured for specimens subjected to rolling experiments of various conditions. Warm rolling of 30% thickness reduction per pass was possible without any side-crack at temperatures as low as 200oC under the roll speed of 30 m/min. The initial microstructure before rolling was the mixed one consisting of partially recrystallized and cast structures. Grain refinement was found to occur actively during the warm rolling, producing a very fine grain size of 7 µm after 50% reduction in single pass rolling at 200oC. Yield strength of 204MPa, tensile strength of 330MPa and uniform elongation of 32% have been obtained in warm rolled sheets.