Effect Of Sample Size On The Quasi-static Compression Test Of Foamed Aluminum And Their Sandwich Panels

Metallic foams are generally subjected to compressive loads in practical application, so the researches on the compression mechanical properties of metallic foams attract widespread attention. However, due to the limited preparation technology, it is difficult to produce large size metal foams. So it is significant to the further development and application of metallic foams to investigate the size effect on its compression mechanical properties. In this paper, the size effect on the compression mechanical properties of aluminum alloy foams are studied systematically by quasi-static compression tests. The researches are outlined as following:1. The effects of aspect ratio of specimen on the quasi-static compression properties of aluminum alloy foams.The compression mechanical properties of the open-cell and closed-cell aluminum foam are studied by experiment. Following results are found in experiments:(1) The change of aspect ratio makes no effects on the elastic modulus of aluminum alloy foams when it less than1. But the compressive strength decreased and the plastic platform became shorter with the increase of aspect ratio.(2) The value of aspect ratio has no influence on the compression mechanical properties of aluminum alloy foams when it greater than1.2. The effects of lamination to the compression mechanical properties of aluminum alloy foams. Comparing the results of compression test between laminated and non-laminated foam specimen, following conclusions are obtained:the elastic modulus, compressive strength of the laminated foam specimen are almost same with the non-laminated one. But the compaction strain decreased with the increase of the number of lamination.3. The effects of the materials and thickness of the face sheets to the compression mechanical properties of sandwich structures with closed-cell aluminum alloy foam as core material.The effects of the materials and thickness of the face sheets to the compression mechanical properties of sandwich structures with closed-cell aluminum alloy foam as core material are studied by experiments, the results are compared with the one without sandwich structure. The results showed that:(1) The compressive strength of the sandwich structure significantly higher than the non-sandwich structure.(2) The plastic platform became shorter and the compaction strain decreased when the radio between the thickness of the face sheets and the height of the core material greater than a critical value λ0.(3) The materials of face sheets have an impact on the value of λ0. The value of λ0of sandwich structures with Iron faces is smaller than the value of λ0of sandwich structures with aluminum faces.