Discontinuous yielding in a low alloy steel

[Quentin_alex]

What could prevent the discontinuous yield (upper and lower) points during a tensile test on a low alloy steel A706 grade?

Thanks.

 

[berkeman]

Are you seeing this in your testing? What is the project? Or is this for schoolwork?

 

[Quentin_alex]

Yes, I am seeing this in my testing. It is for a project.

We mostly run thermomechanically treated bars (Tempcore process) that are A615 grade. They show the typical discontinuous yielding of plain carbon steel. The A706 grade is a low alloy steel predominately strengthened by the addition of manganese and vanadium. I have not found literature on this effect. Could the alloying condition result in a greater degree of continuous yielding rather than discontinuous?

Also, testing conditions are the same for both types of bars.

Thanks.