Search results
Results from the WOW.Com Content Network
The value of Poisson's ratio is the negative of the ratio of transverse strain to axial strain. For small values of these changes, ν is the amount of transversal elongation divided by the amount of axial compression. Most materials have Poisson's ratio values ranging between 0.0 and 0.5. For soft materials, [1] such as rubber, where the bulk ...
Plane-strain compression testing is typically used for measuring mechanical properties and for exploring microstructure development in the course of thermomechanical treatment. [4] During the test the specimen is placed between the punches and the constrain plates. When the upper punch is pushed down during the material test, the specimen is ...
Preconsolidation pressure is the maximum effective vertical overburden stress that a particular soil sample has sustained in the past. [1] This quantity is important in geotechnical engineering, particularly for finding the expected settlement of foundations and embankments. Alternative names for the preconsolidation pressure are ...
t. e. In continuum mechanics, the maximum distortion energy criterion (also von Mises yield criterion [1]) states that yielding of a ductile material begins when the second invariant of deviatoric stress reaches a critical value. [2] It is a part of plasticity theory that mostly applies to ductile materials, such as some metals.
The first term on the right is the constant tensor, also known as the volumetric strain tensor, and the second term is the traceless symmetric tensor, also known as the deviatoric strain tensor or shear tensor. The most general form of Hooke's law for isotropic materials may now be written as a linear combination of these two tensors:
Stress-life (S-N) method S-N curve for a brittle aluminium with an ultimate tensile strength of 320 MPa. Materials fatigue performance is commonly characterized by an S-N curve, also known as a Wöhler curve. This is often plotted with the cyclic stress (S) against the cycles to failure (N) on a logarithmic scale.
Fatigue limit. Representative curves of applied stress vs number of cycles for steel (showing an endurance limit) and aluminium (showing no such limit). The fatigue limit or endurance limit is the stress level below which an infinite number of loading cycles can be applied to a material without causing fatigue failure. [1]
In solid mechanics, the tangent modulus is the slope of the stress – strain curve at any specified stress or strain. Below the proportional limit (the limit of the linear elastic regime) the tangent modulus is equivalent to Young's modulus. Above the proportional limit the tangent modulus varies with strain and is most accurately found from ...