Finite Element Analysis of a Stainless Steel - Research Paper Example

Therefore, this report describes the numerical analysis, conducted using the commercially available finite element solver, ANSYS, and then recommendations are provided as to whether testing or redesign should be the next step. The finite element method (FEM) is a numerical procedure used for finding approximate solutions of partial differential equations (PDE). A partial differential equation is a differential equation containing derivatives involving two or more independent variables. In engineering science, many phenomena are described by partial differential equations, such as displacement or temperature as a function of time and space.

Problems involving PDEs are usually too complicated to be solved by classical analytical methods. Solving PDEs with the method of finite elements is possible today due to rapid solving capabilities of computers. Finite element analysis (FEA), originally used to solve stress analysis problems, is an approach which is used today in many branches of engineering including heat transfer and fluid flow. The material of the part is 2.5 mm stainless steel plate with a Young's modulus of elasticity of 206 GN/m2, a Poison's ratio of 0.

3, and a yield strength of 580 MN/m2. It is assumed that the material has linear elastic properties and is both homogeneous and isotropic (although in reality this is not exactly true for cold-rolled sheets where grain orientation may vary). In addition, it was assumed that no discontinuities or residual stresses are originally present in the material due to manufacturing processes such as forging, rolling and welding. The thickness of the part is assumed constant and is believed to be small enough compared to its width such that shell elements can be used for adequate accuracy in modelling.

Figure 1 shows the buckle modelled in ANSYS. The part is symmetric in two directions and has been separated in the model for simplification. Figure 2 shows the original drawing of the buckle and its symmetry. It is assumed that the geometry of the part is adequately represented by the finite element model developed. Displacements are expected to be relatively small such that a linear approximation will be valid. Figure 1Figure 2The solution of a finite element analysis is only so good as the quality of the mesh.

The smaller the element size, the better the mesh should represent the geometry of the part. For this analysis, two mesh sizes were used: a smaller one where the highest stress concentrations were expected, and a larger one throughout the remainder of the model. The curved sections of the two slots were expected to receive the greatest stresses and were thus meshed with a value of 0.25, while the remained of the buckle was modelled with a 0.51 mesh size. The element type used was the PLANE82, which is a 2D structural solid element with eight nodes.

Eight-noded elements are more accurate for modelling curved boundaries. The PLANE 82 shell element type also allowed for a thickness value in its input properties thus facilitating a 2D problem. In terms of boundary conditions, it was assumed t