Journal of Modern Processes in Manufacturing and Production
Volume:1 Issue: 4, 2012

Considering wide application of dissimilar-thickness resistance spot welds in automotive industry, investigating their failure behavior is of utmost importance. The aim of this paper is to investigate the weld nugget characteristics, failure mode and failure mechanism of dissimilar thickness low carbon steel resistance spot welds during tensile-shear overload test. Mechanical properties of the joints were described in terms of peak load, energy absorption and failure mode. It was found that for well-established weld nuggets, the final solidification line is located in the geometrical centre of the joint. In pullout failure mode, failure is initiated by necking of the base metal at the thinner thickness sheet. Finally, it was concluded that weld nugget size, weld penetration and the strength of the thinner sheet are the main controlling factors of the load bearing capacity and energy absorption capability of dissimilar thickness spot welds.

Sheet metal forming technology to help form a broad layer of rubber over the years has been used so that more than 60 percent of industrial metal parts air using this process are produced. In this method, a flexible rubber layer as the upper half and a rigid form as the lower half is used. Production and preparation of many body parts such as aircraft wings, which has long longitudinal smooth form with large radius of curvature are the most important issues challenging the industry. In this paper, factors shaping technique using rubber pads on the radius of curvature has components and risk factors to help the finite element method has been studied and the factors affecting spring back phenomenon and the reduction in thickness caused by Samples have been taken into consideration and the effect ofvariables such as radius of curvature, thickness of sheet,rubber thickness, hardness of rubber, lubrication conditions,friction, And how lateral edges of the sheet formation has been analyzed. At First validation results to finite element simulations with experimental results were compared to determine if the operation accuracy and then complete the study of other variables mentioned above are addressed. The results indicate that this issue is mentioned parameters significant role in reducing the thickness reduction and the spring is back. The method forming the rubber to help cushion the ideal will be unable to lateral edges with radius of curvature components to produce the desired form we can produce.

In this paper for first time, single, bi-layered and three-layered tube hydroforming processes were numerically simulated using finite element method with ABAQUS/Explicit 6.10. Three types of modeling have been kept with the same geometry, tube material and process parameters to compare between the obtained hydroforming products (bulge height and thickness reduction) using different loading path types. Finite element analysis shows that numerical andexperimental results have a good agreement. In comparison of processes, it became clear that bi- and three-layered hydroforming parts have a lower bulge height, higher thickness reduction and they are more sensitive to the wrinkle forming.

Severe plastic deformation method using equal channel angular pressing (ECAP) has been used as a reliable method to achieve ultrafine grains material. In this research, the plastic deformation behavior of 7075 alloy of aluminum has been simulated by finite element method in three-dimensional method. Different factors such as pressing speed, die channel angle (Φ), die corner angle (Ψ), the frictional status were considered both theoretically and experimentally.Comparing simulative and experimental results, there is a proper agreement between three-dimensional simulation and real condition of ECAP.Overall, the mechanical behavior of material can be predicted by three-dimensional simulation before real ECAP process and it can be widely used to design the process to material to predict the process results.