Search results
Results from the WOW.Com Content Network
Fatigue has traditionally been associated with the failure of metal components which led to the term metal fatigue. In the nineteenth century, the sudden failing of metal railway axles was thought to be caused by the metal crystallising because of the brittle appearance of the fracture surface, but this has since been disproved. [ 1 ]
Within the branch of materials science known as material failure theory, the Goodman relation (also called a Goodman diagram, a Goodman-Haigh diagram, a Haigh diagram or a Haigh-Soderberg diagram) is an equation used to quantify the interaction of mean and alternating stresses on the fatigue life of a material. [1]
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] Some metals such as ferrous alloys and titanium alloys have a distinct limit, [ 2 ] whereas others such as aluminium and copper do not and will eventually fail even from ...
[2] [3] The law provides a mathematical model to predict the number of cycles to failure (N) based on the applied stress amplitude (). A High Cycle Fatigue Test is used to determine material behaviour under repetitive cyclic loads. This test aims to establish the stress-cycles-to-failure characteristics of materials, primarily utilising an ...
This simplification allows the number of cycles until failure of a component to be determined for each rainflow cycle using either Miner's rule to calculate the fatigue damage, or in a crack growth equation to calculate the crack increments. [2] Both methods give an estimate of the fatigue life of a component.
Strength parameters include: yield strength, tensile strength, fatigue strength, crack resistance, and other parameters. [citation needed] Yield strength is the lowest stress that produces a permanent deformation in a material.
Low cycle fatigue (LCF) has two fundamental characteristics: plastic deformation in each cycle; and low cycle phenomenon, in which the materials have finite endurance for this type of load. The term cycle refers to repeated applications of stress that lead to eventual fatigue and failure; low-cycle pertains to a long period between applications.
Material failure theory is an interdisciplinary field of materials science and solid mechanics which attempts to predict the conditions under which solid materials fail under the action of external loads.