Relationship among tensil strength, yield strength and enlongation

Cold rolled or cold drawn seamless steel tube is used in mechanical structure and hydraulic equipment of high dimensional accuracy and suface finish good.

Ray seamless steel tube normally use 1010,1020,1045 etc high qaulity carbon steel and 16Mn or 30CrMo or 40Cr etc alloy steel tube .

When seamless steel tube finished, most client will ask how much tensile strength and yield strength of pipes, why they want to know mechanical properties of finished pipes, today we will tell the reason as below:

Tensil strength is gained through uniaxial tensile test of metal material mechanics performance index.

Tensil sterength represents the metal materials under the action of external force resistance to deformation and failure.

It has its’ own calculation method: Tensile strength= breaking load/ initial sample cross-sectional area. But if the result of calculateion doesn’t mean its’ actual tensile strenght.When metal has obvious plastic deformation, the calculation with the cross-sectional area of the real sectional area should be the final measurement, the tensile strength is called the true tensile strengt.

Yield strenght is another one of the important mechanics property of metal material indicators.

Yield strenght represents the metals for inital plastic deformation resistance. But in professional, we cann’t say like that.Cause on tensile curve, some metal material have obvious yield point, but some material don’t have obvious yield strength.Especially for some uneven microstructure material. So we have to definition yield strength when the plastic deformation is to a certain extent and the corresponding resistance.But it isn’t accurate reflect the beginning of plastic deformation.

As described above:

Tensil sterngth means the strength of maximum deformation resistance.

Yield sterngth is the ability to resist initial deformation.

After we explain Tensil strength and yield strength, now let us know more information about enlongation.

Enlongation describe the plastic material peformance indicators.It shown the percentage for samples after tensil frcture the total deformation of length and the original gauge length.

What’s the relationship among tensil strength, yield strength and enlongation?

If material is different, they don’t have relationship. If material is same.Tensil strength ,yield strength and enlongation there are some relationships:

If client want higher tensil strength and yield strength, then enlongation will be lower.At the same time, the only way to improve the strength and maintain elongation was fine grains, other methods of improving strength more or less will reduce the elongation of the material.As for the material yield strength and tensile strength between associated primarily and material strain hardening index, index is higher, the greater the difference between the small smaller difference between index.

If you have more questions, please feel free to contact Changzhou Raymond Steel Tube Co.,Ltd.