The impact response of fiber metal laminates (FMLs), has been investigated with experiments and numerical simulations, which is reported in this article. Low-velocity impacts were carried out to study the effects of metal type and thickness within FMLs. Glare5-3/2 laminates with two aluminum layer thicknesses and a similar FML containing magnesium sheets were impacted by drop weight tests. Also, a major part of this study was to accomplish a dynamic non-linear transient analysis to study the impact response of FMLs using the commercial finite element (FE) analysis code ABAQUS. By reviewing different approaches of modeling constituents of an FML, it is shown that the appropriate selection of elements has more significant role than failure criterion to predict acceptable results for this type of laminate and loading. The good agreement obtained between experimental and numerical results verifies the possibility of relatively simpler simulation by FE-analysis to predict overall response of FMLs under impact loading.

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Tube spinning, without mandrel, is a common process used for manufacturing pressure vessels, e.g. CNG (Compressed Natural Gas) capsules for automotive industry and fire extinguishers. The process is carried out at an elevated temperature for forming a dome on thick wall steel tube ends. Two of the most important control parameters in the process are the “roller contact start point” (RCSP) and spinning feed (pitch), both of them highly affecting the process time and deformation behavior of the tubes and therefore success and quality of the product. In this article, using a three-dimensional dynamic explicit finite element model, the effects of these parameters are investigated on circumferential, axial and radial (thickness) strains of the formed tube in three thickness layers of the tube wall. The model is also verified by experiment. While circumferential strain is shown to be independent of the feed, axial and thickness strains are highly affected by both the feed and roller contact start point. It is shown that when the roller contact start point distance from the free end of the tube increases, there is a risk of indentation instead of normal bending behavior. It is also shown that axial strain has an inverse relation with feed, i.e. decreasing the feed results in further elongation of the tube. On the other hand, thickness strain increases by increasing the feed, so bigger thicknesses are expected in domes manufactured by higher feeds. In addition, it is shown that increasing the feed results in a decrease of the equivalent strain. The amount of residual stress (regardless of the temperature change) increases with increasing feed and its distribution is more uniform for higher distances of the contact start point from the free end.

A 3-D Dynamic explicit finite element model of metal shear spinning, is developed and solved for different nose radii and feed rates. Several amounts are applied to spinning roller nose radius and feed rate, then Axial, tangential and normal forces are calculated for each combination of parameters. The results are checked with a series of experimental tests in which the process parameters are varied according to the finite element model. The experimental values are shown to be in relatively good agreement with the outcomes of the finite element model.