Steel is an indispensable material in our lives. How much you know about steel? What is the yield point, what is the yield strength, if you know all these knowledge? Below on the relevant knowledge to make an introduction.
1) Yield point of steel (s)
Steel or specimen in the tensile, when the stress exceeds the elastic limit, even if the stress is no longer increased, while the steel or the sample continues to occur significant plastic deformation, called this phenomenon yield, and yield the phenomenon of the minimum stress value As the yield point.
Let Ps be the external force at the yield point s, Fo is the cross-sectional area of the specimen, then the yield point s = Ps / Fo (MPa), MPa is equal to N (Newton) / mm2, (MPa = 106Pa, Pa: Pascal = N / m2).
2) Steel yield strength (0.2)
Some of the metal material yield point is very obvious, there are difficulties in measurement, in order to measure the yield properties of the material, the provisions of the permanent residual plastic deformation is equal to a certain value (usually 0.2% of the original length) stress, known as the conditions Yield strength or short term yield strength 0.2.
3) Tensile strength of steel (b)
Material in the stretching process, from the beginning to the fracture of the maximum stress reached when it indicates that the ability of steel to withstand fracture strength and tensile strength corresponding to the compressive strength of bending strength and so on.
Let Pb be the maximum tensile force before the material is pulled, Fo is the cross-sectional area of the specimen, then the tensile strength b = Pb / Fo (MPa).
4) Steel Elongation (s)
Material in the pull-off, the plastic elongation of the length of the length of the original sample called the percentage of elongation or elongation.
5) Steel yield ratio (s / b)
Steel yield point (yield strength) and tensile strength ratio, known as the ratio of yield strength ratio is greater than the greater the reliability of structural parts, the general carbon steel yield ratio of 0.6-0.65, low-alloy structural steel 0.65-0.75 alloy structural steel is 0.84-0.86.
6) Steel hardness
Hardness that the resistance of the material into the surface of the hard object the ability of it is an important indicator of metal materials, the general hardness of the higher hardness of the common indicators of hardness Brinell hardness and Vickers hardness.