To assess if a structure is suitable for the intended purpose, the results of a FE analysis have to be compared to acceptance criteria, also called allowables. For a stress analysis, allowables could be e.g. equivalent stresses (see https://hosting243536.ae9a8.netcup.net/equivalent-stress/) or deflections. The Factor of Safety (FoS) is...
The stress results of a FE analysis are three-dimensional tensors, see: (https://hosting243536.ae9a8.netcup.net/stress-tensor/) Material properties including Yield Strength and Ultimate Strength are however usually derived from uniaxial tests, e.g. tensile tests, see: (https://hosting243536.ae9a8.netcup.net/tensile-tests/) Depending on the material used and its failure mode, there are different conversions done: For...
For anybody who wants to assess FEA results, it is important to understand the concept of the Stress Tensor. A tensor is a mathematical entity. Other, more commonly known mathematical entities are scalars and vectors (although these two are actually just special forms of tensors). Simply speaking,...
The data obtained from a Tensile Test (https://hosting243536.ae9a8.netcup.net/tensile-tests/) are forces and displacements. In order for this to be useful to an engineer, the applied force has to be converted into a stress. (https://hosting243536.ae9a8.netcup.net/stress-strain-curves/) There are two types of stress which can be calculated, Engineering Stress and True...
In Hooke's Law (https://hosting243536.ae9a8.netcup.net/law-of-elasticity/), the Spring Constant k describes the relation between an applied load and the resulting deformation of a body. It depends on both the shape (geometry) of the part as well as its material. To have a constant that is just depending on the...
The Law of Elasticity, or Hooke's Law, is a brilliantly simple form to express the elastic deformation of a body. In our times, this Law of Physics is practically known by most people, but it was revolutionary when first stated in 1660 by the British...
The shape of a Stress-Strain Curve allows a handy overview on the deformation behaviour of a material. Please read (https://hosting243536.ae9a8.netcup.net/stress-strain-curves/) for information on how Stress-Strain Curves are generated. For many materials, the Stress-Strain Curve is a straight line up to the Yield point. Such a behaviour is...
Elasticity is the deformation of a solid material that is completely reversed once the external load that has caused the deformation has been removed. That means, after removing the external load, the part is again undeformed. Plasticity in contrary is the non-reversible deformation of a solid...
Mechanical material properties are usually established by specimen tests, most commonly tensile tests (https://hosting243536.ae9a8.netcup.net/tensile-tests/), with the results shown as force vs elongation diagrams. The results of a tensile test are hence depending on the specimen's geometry: A bigger cross section would withstand a higher force than...
FEA-Solutions (UK) Ltd delivers accurate stress analysis results. This requires that all input data is accurate as well, including the mechanical properties of the materials used in your design. Mechanical properties are usually established by performing specimen tests. Most commonly used, in particular for metals, are...