1. On your formal data sheet list load, elongation, engineering stress, strain and true stress at each interval. 

For a copy of the Table in Microsoft Word format click here. (If your browser can not open this link, check your email for a copy of this file)

For a copy of the Table in Microsoft Excel format click here. (If your browser can not open this link, check your email for a copy of this file)

2. Plot a graph of stress as ordinate versus strain as abscissa.  (Include true stress and engineering stress)
3. Determine the ultimate stress (Tensile Strength) from the engineering stress-strain curve.
4. Replot the stress versus strain values for the first 13 data points. 
5. Find the yield point . (How many psi ?) 
6. What is the value of the proportional limit (psi) ? 
7. Replot the stress versus strain values for the first 10 data points. If you are using Microsoft Excel, click on data points and select CHART, ADD TRENDLINE, LINEAR. Then click on OPTIONS, click DISPLAY EQUATION ON CHART and DISPLAY R-SQUARED VALUE ON CHART. This will give you a linear curve fit. The slope of the equation gives the Modulus of Elasticity. R² value indicates how good the curve type agrees with the data. If R ² equals 1 or close to 1 it means a good curve fit.



8. Using the graph as described in Step 7, calculate the modulus of elasticity (psi). (You may also use MDSOLIDS software.)
9. Calculate % elongation and % reduction in area. 
10. Using the area under the curve, calculate the modulus of toughness.  
11. How much is the breaking stress (rupture stress) ?

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