| Summary: | 碩士 === 逢甲大學 === 機械工程學系 === 89 === Cell metal foams is kind of up-to-date material. As large number cells exist in matrix, the material owns excellent mechanical properties. The research is focus on compression behaviors and energy absorption capacities of cell metal foams when the compressive force acting on the material. Besides, we changed the conditions of strain rate and temperature in order to find the relation between with compression properties and these conditions. We established the technique of scan system and image processing that to observe the cells changed.
Experimental results show that cell metal foams under compression test, the compressive strength will reach peak point and into the plateau regimes. Regarding to the results of different temperature and strain rate conditions, the compressive strength of cell metal foams will increase as temperature decreases but not sensitivity to the strain rate. The energy absorption capacities and material specific gravity are closely related. in addition to, the material will become more pliable in high temperature. so that, densification stage in the beginning point will be delayed, and the length of the elastic stage will be shortened.
Finally, using image processing, we obtain the clearly deformation mechanisms of cell metal foams such as the cells shape change. However, different cell size, number, thickness of wall, and break position of foam materials are bring about different behaviors of compression. According to the deformation state of cell shape, the deformation degree of cell will increase as approach outside of compression surface. Besides, the strain rate agree with the whole of cell lose rate.
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