MEE 324 Structural Mechanics Lab Lab One: Tension Test (Elasticity & Plasticity)\ Instructors: Dr. Masoud Yekani Fard and Dr. Dallas Kingsbury\ Objectives\ The objectives of this lab experiment are as follows:\ a. Carry out the tensile test on plain carbon steel and aluminum specimens to measure Young's Modulus (E), y strength (

S_(Y)

), ultimate tensile strength (SUTS), % elongation, percentage of reduction of area, fracture strength (

S_(F)

and power-law plasticity coefficients.\ b. Plot the tension stress-strain relationship them. Use linear regression and zero shift to discard non-meaningful data and verify the validity of your results using literature values.\ c. Observe necking and other failure analyses on and near the fracture surface of ductile samples.\ d. Prepare a lab report to (i) describe the experiment and the results; (ii) compare the results with the expectations from theory (MAE 213 and MEE 322); (iii) discuss the possible reasons for the differences between theory and the experimental observations.\ 2. Description\ A loading machine will be used (Fig. la) to apply axial tensile load "P" at the ends of a bone-shaped specimen. A load cell and a strain gauge (or an extensometer (Fig. 1b)) will measure load and displacement (or strain) data points for the entire test. The collected data must be analyzed to determine all the quantities of interest related to the objectives listed in Section 1. The experiment will be done in displacement control with a

1m(m)/(m)in

speed. The load will be increased until the complete fracture of the specimen. The lab manager (or TAs) will show how to set the parameters before the test.