Determine, E, 0.1% proof stress, tensile strength, % elongation after failure

Question

Maximum force was 13.8kN and final length between gauge warks was 53.35mm

 

Load (N)                      2,000        4,000     6,000    8,000      10,000     11,000    12,000      13,000

 

Extension (mm)         0.060         0.110    0.175    0.225       0.285       0.325       0.475        0.58

 

Answer 1

Calculate the E.

First draw the stress-strain curve:

From the graph:

Modulus of elasticity, E = stress/strain

                                    =10000/0.285

                                    =35087.72 N/mm^2

                                     =35087.72 MPa

0.1% proof stress means 0.1% of E.

σ proof  = (0.1/100) *35087.72

          =35.08 MPa

Calculate the tensile strength.

σy= stress/strain

    =11000/0.325

   =33846.154 N/mm^2

   =33846.143 MPa

Strain at failure is 0.58 mm

Initial gage length ,0.06 mm

% of elongation =( 0.58-0.06)*100/(0.06)

                         =52%

 

Comments

Thank you so much, perfectly clear on what you've said and it helped me a lot.