Ultimate tensile stress of material

[songoku]

Homework Statement

The diagram shows the stress-strain curve for a metal. Which label corresponds to the Ultimate Tensile Stress for this metal?

Relevant Equations

None

My answer is A but the answer key is B.

I don't understand why B. I would think B is the breaking point.

Thanks

 

[haruspex]

Homework Statement:: The diagram shows the stress-strain curve for a metal. Which label corresponds to the Ultimate Tensile Stress for this metal?
Relevant Equations:: None

I would think B is the breaking point

Is there a difference?
https://en.wikipedia.org/wiki/Ultimate_tensile_strength

Edit… I misread the article at that link the first time. Reading it again, it agrees with you that A is the UTS.

 

[erobz]

The “Engineering Stress-Strain”curve is misleading in that area. The “True Stress-Strain” curve is what you need to consider.

 

[Martin TSK]

Homework Statement:: The diagram shows the stress-strain curve for a metal. Which label corresponds to the Ultimate Tensile Stress for this metal?
Relevant Equations:: None

View attachment 313238

My answer is A but the answer key is B.

I don't understand why B. I would think B is the breaking

 

[Martin TSK]

A is UTS and B is Breaking point

 

[Lnewqban]

... My answer is A but the answer key is B.

I don't understand why B. I would think B is the breaking point.

Thanks

It could be considered point B, as the material is necking and reducing its cross-section resisting the traction force.

Please, see:
https://www.substech.com/dokuwiki/doku.php?id=tensile_test_and_stress-strain_diagram

 

[songoku]

Thank you very much for the help haruspex, erobz, Martin TSK, Lnewqban