A tensile test was conducted on an Instron tensile machine using a 3/16 inch copper rod. Using data acquired stress and strain was calculated and plotted on Excel to analyze stress strain curve. Modulus of elasticity, 0.2% yield stress, ultimate tensile stress and % elongation were also calculated. Introduction
A tension test is probably the most fundamental type of mechanical test you can perform on material. Tensile tests are simple, relatively inexpensive, and fully standardized. By pulling on something, you will very quickly determine how the material will react to forces being applied in tension. As the material is being pulled, you will find its strength along with how much it will elongate. During tensile testing the tensile load is measured by a load cell while extension of the specimen is measured over the gauge length. Data is provided by a computer program, which is used to determine stress and strain, therefore allowing a stress-strain curve to be plotted. Experimental Procedure
A 3/16“ diameter specimen (Cu rod) was loaded onto an Instron tensile testing machine. The appropriate extensometer was attached for the given specimen and gage length. Calibration of the extensometer and load cell was done prior to tensile testing. Data is recorded until specimen reaches ultimate tensile strength and snaps; recorded data is processed into Excel to create a Stress-Strain curve. Equipment used in this lab was Instron tensile testing machine, 3/16” copper rod to complete the lab.
Results and Discussion
Our results from the Instron tensile machine are shown below in Table 1, which were converted to Strain and Stress shown in Table 2 using [∆l (extension) /5.25 in]. to get Strain and [load (lbs) / (π/4) * d^2] to get Stress. After plotting the data a strain stress curve was determined, shown below at Figure 1. Using equation of line shown in Figure 3, the line was used to determine 0.2% yield strength offset and point of...
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