Assignment

1. Each person is expected to perform two metals hardness tests and one polymer test.  A different material can be used in each of the three tests.  Determine beforehand the testing objective for your group (each person in the group tests a different type of steel, each person tests the same materials, etc.) in order to make a wise decision concerning specimen selection during the tests.

• Available Materials
• Available Equipment
• Data Sheet

2. References for metals hardness testing

• ASTM E10 - Brinell
  • Simplified Brinell hardness testing procedures
• ASTM E18 - Rockwell
  • The distance between the center of two adjacent indentations shall be at least three times the diameter of the indentation. (section 7.10)
  • The distance from the center of any indentation to an edge of the test piece shall be at least two and a half times the diameter of the indentation. (section 7.10.1)
  • Tables 11 and 12 contain correction factors for cylindrical specimens.
  • Simplified Rockwell hardness testing procedures
• Conversion tables and formulas from one hardness scale to another
  • ASTM E140
  • Conversion table
  • Conversion formulas
  • Hardness conversions at eFunda
  • Instron hardness chart
  • Mitutoyo hardness chart

3. References for polymer hardness testing

• ASTM D785 - Rockwell
• ASTM D2240 - Type A, B, C, D, DO, E, M, O, OO, OOO, OOO-S, and R durometers
• ASTM C661 - Type A2 durometers

4. Summarize your results, as per your teachers' instructions, and submit at the start of the next lab class.  Attempt to explain significant variations from the reference values.

• Sample Results