Is elongation a measure of plastic deformation?

I did a tensile test of a metallic alloy, and I want to calculate it's elongation. Would it simply be the (failure strain - yield strain)?


For reference, I got the following values from the test:


Yield strain: 0.015
Yield stress: 404 MPa
Failure strain: 0.22
Failure stress: 592 MPa


Would the elongation simply be 0.22-0.015 = 0.205


0.205 \* 100 = 20.5%? I.e. simply the amount of strain that was done plastically?


Thanks in advance!




I measured elongation and reduction of area on many bars, shapes, materials. Never calculated it, never heard on anyone calculating elongation. The elongation is the primary measure of ductility. The tensile machine graph puts out a strain which is interesting , but we always measured the bars to be sure. That also give you a look at the fracture surface which can also be informative. What are the units of your 0.015 strain; % ?, mm ? ( inches) of what gage length? Also various specifications have different definitions of yield.


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