Materials Technology

Material Testing

Overview – Testing MaterialsHardness Testing

Direct Reading Hardness Testing Machine (Vickers or Brinell)

Measures the materials resistance to indentation or scratching

Indenter

Test Component Placed on Table

Table Height Adjustment

Activating lever

Hardness Value Read Directly From Dial

Overview – Testing MaterialsVickers Hardness Testing

Measures the materials resistance to indentation or scratching

A square pyramid shaped indenter (point angle 136°) is forced into the specimen. The diagonal length of the indentedsquare is measured. This measurement is taken by a special microscope for accuracy.It is then converted into a Vickers hardnessnumber

Overview – Testing MaterialsBrinell Hardness Testing

Measures the materials resistance to indentation or scratching

The Brinell hardness test uses a hardened steel or tungsten carbide ball of 10mm, 5mm or 1mm diameter. The diameter of the indentation is measured and it is used to indicate the hardness of the material

Overview – Testing Materials`Simple Workshop Test (Hardness)

Heavy Plunger

Clear Acrylic Tube

Specimen to be Tested

Steel Ball Bearing

The Plunger is dropped from a 500mm height onto different materials.

The indentations on each test piece are measured.

The deeper the indentation – the softer the material

Overview – Testing MaterialsIzod Impact Test

Measures a materials toughness

Test Specimen Held Vertically

Vice

Pendulum

Start Position of Pendulum

Scale to read energy absorbed in breaking the specimen

Overview – Testing Materials`Izod Impact Test

Measures a materials toughness

•The Specimen is held vertically in a vice

•The notch on the specimen faces the pendulum

•The striking energy of the pendulum is 167 Joules

Pendulum

Vice

Specimen

Overview – Testing Materials`Charpy Impact Test

Measures a materials toughness

•The Specimen is held horizontally – between two supports

•The notch on the specimen faces away from the pendulum

•The striking energy of the pendulum is 300 Joules

Pendulum

Support

Specimen

Overview – Testing Materials`Simple Workshop Test (Toughness)

This is another comparative test.

The specimen pieces are held vertically in a vice and hit with a hammer

It is important to wear a face shield or goggles and for spectators to stand well back.

Brittle materials will fracture and possibly splinter.

Specimen

Vice

Hammer

Ductile Material

`Overview – Testing Materials`Simple Workshop Test (Deflection)

This is another comparative test

The specimen is placed on the supports

Weights are placed on the platform, pushing the plunger down causing the specimen to deflect

Specimens can be tested to destruction or their deflection is measured when the same weight is applied to each in turn

Specimen

Supports

Plunger

Weights Platform

Overview – Testing Materials`Tensile Testing

Measures a materials tensile strength

Simple Tensile Testing Machine

Clamps for Holding SpecimenDial Gauge to Measure

Extension of Specimen

Overview – Testing Materials`Simple Workshop Test (Stiffness)

This is a comparative test. The material to be tested is clamped to a bench.

Weights are applied to the free end.

The amount of deflection of each material is measured and compared with each other

Deflection

Applied Weights

Clamped

Specimen