What is the ultimate strength and how can it be determined?

5 answers

www.nde-ed.org/EducationResources/CommunityCollege/Materials/Mechanical/Tensile.htm
At what point does permanent deformation occur? What materials are most resistant to permanent deformation?
Plastic behavior: This permanent deformation behavior occurs when the tensile (or compressive) uniaxial stress reaches sy.

Hard materials like diamond, nitrided steel and even most plastic are resistant to permanent deformation.
Thank you sir!
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