What factors affect the fatigue and creep of metals?
In addition to these three basic factors, there are a host of other variables, such as stress concentration, corrosion, temperature, overload, metallurgical structure, and residual stresses which can affect the propensity for fatigue.
What type of stresses cause fatigue failure?
Fatigue failures are often associated with components experiencing cyclic stresses or strains resulting in permanent damage. This accumulates until it develops into a crack which propagates and causes failure. The process of damage accumulation and failure caused by cyclic loading is called fatigue.
What is constant amplitude fatigue limit?
A constant amplitude fatigue loading (or constant amplitude loading) is a fatigue loading in which all the load cycles are identical. A load cycle is usually called either just a cycle or a fatigue cycle.
What effects fatigue life?
Fatigue life is influenced by a variety of factors, such as temperature, surface finish, metallurgical microstructure, presence of oxidizing or inert chemicals, residual stresses, scuffing contact (fretting), etc.
What are the factors affecting the fatigue failure?
Thermal fatigue can be catergorized into thermal loading, high temperature, and low temperature fatigue. The mismatch of thermal coefficients of expansion between two mating parts induces thermal stress when temperature changes.
Which of the following is failure of material due to cyclic stress?
Fatigue
What is the difference between failure due to static load and fatigue failure?
Answer: Static failure:- Static failure presence of the cracks in the material. It depends on the material and its relative strength in compressive, tension and shear and it also depends on the type loading. Fatigue failure:- Fatigue failure is defined as the time-dependent fracture under cyclic loading.
Under what conditions can metals be made to fatigue?
Metal fatigue, weakened condition induced in metal parts of machines, vehicles, or structures by repeated stresses or loadings, ultimately resulting in fracture under a stress much weaker than that necessary to cause fracture in a single application.
How can you increase the resistance to fatigue of a metal alloy?
Four measures that may be taken to increase the fatigue resistance of a metal alloy are: (1) Polish the surface to remove stress amplification sites. (2) Reduce the number of internal defects (pores, etc.) by means of altering processing and fabrication techniques.
What is the reason for fatigue failure Mcq?
Explanation: Fatigue failure occurs due to submicroscopic cracks. These develop on the surface of a material. These eventually coalesce into visible crack.
Why do we use alloys rather than pure metals for many uses?
Alloys are, for example, generally harder than pure metals. They are made up of atoms of different sizes, rather than being uniform. Alloys also tend to have better corrosion resistance than pure metals, and are more versatile for manipulating into different forms.