Overview of PASCO Material Testing

Sep 17, 2024

Lecture Notes: PASCO Scientific Material Testing Apparatus

Presenters

  • Chong
  • Justin, Mechanical Engineering Student, California State University Sacramento

Overview of Material Testing Apparatus

  • PASCO Scientific's material testing apparatus
    • Manual crank connected to an encoder
    • Encoder connected to a lead screw with a carriage
    • Carriage allows attachment of material sample
    • Equipped with a force sensor for measuring material properties in compression and tension

Included Components

  • Material testing apparatus
  • Safety guards (no need for safety glasses)
  • Calibration test piece for software calibration
  • USB link for connection to a laptop
  • Single user license of Capstone software for data analysis
  • Starter kit for immediate setup

Additional Accessories

  • Shear accessory
  • Bending accessory
  • Flat coupon adapter
  • Adapters for structure kits and testing on structure beams

Materials for Testing

  • Nailed steel, regular steel, brass, aluminum
  • Two types of plastic (clear plastic with polarizing lens)

Demonstration Setup

  • Remove safety cover
  • Use brass piece from starter kit
  • Set up webcam for test sample filming
  • Hardware setup in Capstone software
    • USB link and webcam connection
    • Configure material testing unit
    • Switch sign for tensile test travel direction

Calculating Stress and Strain

  • Stress equation: Stress = Force / Cross-sectional area
    • Test sample diameter: 3.3 mm (converted to meters for consistency)
    • Test sample length: 35 mm
  • Enter equations into Capstone software using Calculator
    • Stress in SI units (Pascal) and imperial units (PSI)
    • Strain: Strain = ΔL / L (unitless)

Data Collection and Analysis

  • Record movie with synchronized data
  • Use Capstone to display video and graph simultaneously
    • Stress on one axis, strain on the other
    • Adjust graph view for clarity
  • Zero the sensor before data collection
  • Collect data by cranking manually
    • Observe elasticity, plasticity, and yield points
    • Playback recorded video for review

Additional Experiments

  • Hysteresis demonstration: explore plasticity and elasticity
  • Show work hardening

Closing

  • Thanks to Justin and audience for participation
  • Encourage further exploration of apparatus capabilities