Tensile Testing Masterclass

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Tensile Testing Masterclass
Martin Carr(Schools Liaison Officer)Department
of MaterialsParks Road Oxford OX1 3PHTel.
01865 273 710 EmailMartin.Carr_at_materials.ox.ac.u
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Aims

• To raise awareness of Materials Science to
  schools.
• To encourage closer contact between schools and
  Materials Science Departments.
• To enable schools to have access to expertise and
  equipment that is beyond the reach of most
  schools.

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Pedagogy - Preliminary

• Teachers should introduce Tensile Testing, strss
  strain charts and relevant terminology BEFORE
  the Masterclass.
• Plasticine and sand Model
• Preliminary Experiments

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Pedagogy - Preliminary

• Plastic behaviour of metals is modelled by the
  plastic behaviour of plastic-ine.
• Sand mimics the effect of carbon
• Measurements and observations can be made.
• The Feel of the stress-strain chart.
• Fracture surface appearance.
• Necking.
• Ductility.

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Pedagogy - Masterclass

• Tensile Test Specimens are broken. Measurements
  and Observations are made and compared to C
  content
• increase in length
• reduction in area
• Microstructure
• Hardness
• Strength

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Results Stress-Strain Charts
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Results Mechanical Properties
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Overview

• Initial learning curve is very steep.
• Students split into groups of about 4
• Team work
• Allocation of responsibilities
• Collection of data.
• Some, not all, students get good results.
• Data from each group is collected at the end of
  the session and copied onto a USB memory stick
  for the teacher to take away together with
  specimen data.

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Benefits To The School

• Experience of working in an undergraduate
  teaching lab on a cut-down undergraduate
  experiment.
• Interaction with student demonstrators.
• Concrete experience of an abstract part of a
  teaching course.
• Teacher could use data for coursework.
• Links with the department which could be
  developed further.

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Benefits To The Department

• One aspect of Materials Science is highlighted.
• Opportunity to raise awareness further
• Links with teachers may result in more sixth
  formers considering Materials Science as a
  career.
• Can be linked with Aspiration / Gifted and
  Talented and similar initiatives.
• Promotes Physical Sciences and Engineering on a
  broader basis.

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Materials Used

• Material Supplier
• Orchard Materials Ltd
• Unit 7, Brunel Way
• Thornbury Industrial Estate,
• Thornbury
• Bristol   BS35 3UR

Remko Iron 0.02C 080A15 0.18C 080A42 0.41C 070M
55 0.54C S202 0.82C

• Heat Treatment in House
• Normalise all steel in the same way
• Heat in the furnace and hold at 860C for 1 hour.
• Remove from furnace and air cool out of draughts.

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Engineering Supplies

• CNC Machining
• Jacobs and Sons
• Unit 6, Park Farm Industrial Estate
• Greet
• Gloucestershire,   GL54 5BX
• For bulk orders, machining approx. 1.55 to 1.65
  each.