Concepts:
● Stress
● Strain
● Young's Modulus
● Yield Point

Method
In this experiment, students test a variety of materials by stretching them until failure under the tensile load. The sample is placed in the holder and firmly held on both ends. By turning the hand crank, the sample is stretched in one dimension. During the stretching, the Force Sensor measures the applied force through the 5 to 1 lever arm. This allows the maximum allowable force in the experimentto be 250 N. Simultaneously, the Rotary Motion Sensor measures the stretch of the sample real-time. Using PASCO Capstone™ software, the stress and strain can be calculated and graphed versus one another. The slope of the stress-strain graph in the elastic region is known as Young's Modulus. The transition between elastic and plastic deformationis known as the Yield Point; this point can be easily determined from the PASCO Capstone graph.

Young's Modulus for steel is determined using a linear curve fit on the elastic portion of the curve.

PASCO Advantage
Students experience the tensile failure of various materials and collect critical measurements real-time with PASCO probeware. PASCO Capstone graphs and calculations are created to extend student understanding of materials science. The compact size of the Stress-Strain Apparatus makes it ideal for any laboratory or classroom setting.

Included Test Coupons
The set of test coupons included with the Stress/Strain Apparatus contains: steel, annealed steel, aluminum, two thicknesses of brass, and four different types of plastic. Ten test coupons of each material come with the unit.

  Plastic Coupons

  Metal Coupons