Search results
Results From The WOW.Com Content Network
The ultimate tensile strength of a material is an intensive property; therefore its value does not depend on the size of the test specimen.However, depending on the material, it may be dependent on other factors, such as the preparation of the specimen, the presence or otherwise of surface defects, and the temperature of the test environment and material.
This region starts as the stress goes beyond the yielding point, reaching a maximum at the ultimate strength point, which is the maximal stress that can be sustained and is called the ultimate tensile strength (UTS). In this region, the stress mainly increases as the material elongates, except that for some materials such as steel, there is a ...
ASTM A992 steel has the following minimum mechanical properties, according to ASTM specification A992/A992M. Tensile yield strength, 345 MPa (50 ksi); tensile ultimate strength, 450 MPa (65 ksi); strain to rupture (sometimes called elongation ) in a 200-mm-long test specimen, 18%; strain to rupture in a 50-mm-long test specimen, 21%.
Tensile testing, also known as tension testing, [1] is a fundamental materials science and engineering test in which a sample is subjected to a controlled tension until failure. Properties that are directly measured via a tensile test are ultimate tensile strength, breaking strength, maximum elongation and reduction in area. [2]
The factor of safety on ultimate tensile strength is to prevent sudden fracture and collapse, which would result in greater economic loss and possible loss of life. An aircraft wing might be designed with a factor of safety of 1.25 on the yield strength of the wing and a factor of safety of 1.5 on its ultimate strength.
Strength depends upon material properties. The strength of a material depends on its capacity to withstand axial stress, shear stress, bending, and torsion.The strength of a material is measured in force per unit area (newtons per square millimetre or N/mm², or the equivalent megapascals or MPa in the SI system and often pounds per square inch psi in the United States Customary Units system).
The ultimate strength is the maximum stress that a material can withstand before it breaks or weakens. [12] For example, the ultimate tensile strength (UTS) of AISI 1018 Steel is 440 MPa. In Imperial units, the unit of stress is given as lbf/in 2 or pounds-force per square inch. This unit is often abbreviated as psi.
Typical values of the limit for steels are one half the ultimate tensile strength, to a maximum of 290 MPa (42 ksi). For iron, aluminium, and copper alloys, S e {\displaystyle S_{e}} is typically 0.4 times the ultimate tensile strength.