Question

For each of the product applications below answer the material design, requirement and selection questions using the following format.

a) List the desired material properties (not limited to mechanical properties) for the intended application

b) What are the typical materials that are used for the intended application? If you are unable to find an exact answer, predict the material category (such as metals/alloys, ceramics, polymers, composites etc.) that you would select.

c) What mechanical property would you test and using what choice of test (s) – both for checking the suitability of your chosen material and for product safety.

1) Turbine blades for a jet engine

2) Axle for Baja vehicle

3) Non-stick coating for a cooking pan

4) Protective cover/coating for a smart phone

5) Gears for wind turbine

6) Bearings

7) Bleachers

8) Body armor hard plates

9) Hockey puck

10) Underground fiber optic cables

11) Protective sheath for underground cables

Answer 1

1) Turbine Blades for a jet engine- a) material properties- high thermal conductivity, low coefficient of expansion, good fatigue of strenght

b) Materials used- stainless steel, aluminium, nickel based super alloys.

c) Testing Mechanical Property and choice of test- corrosion test using electrochemical tests

2) Axle for baja vehicle- a) material properties- castability, resistance to bending and breaking, corrosion resistance

b) materials used- chrome-molybdenum steel

c) Testing- ultasonic testing for detecting internal flaws

3) nonstick coating for a cooking pan- a) Material properties- high melting point, low thermal diffusivity

b) materials used -polytetrafluoroethylene, ceramics

c)material testing- abrasion test measures coating resistant to constant scrubbing

4) protective cover for a smart phone- a) material properties - strong, lighter

b) material used- thermoplastic polyurethane, plastic etc.,

c) material testing- scratch test

5)gears for wind turbine- a) material properties- high resistance to oxidation, high tensile strenght

b) materials used- cast iron

c) material testing- noise and vibration testing,

6) bearing a)material properties- low coefficient of friction, low thermal expansion ,high fatigue strenght

b) materials used- stainless steel

c) material testing- ball bearing test rig enables to test ball bearing for their lifetime under vaccum at +300 degree celcius

7) bleacher- a) material properties- strong

b)material used- aluminium tube

8) Body armor hard plates- a)material properties- high hardness, low weight

b)material used- kevler

c) material testng- measuring ballastic performace of armor by determining the kinetic energy of bullet at impact

9) hockey puck a) material properties- higher tensile strenght, resistance to abrasion

b) material used- vulcanized rubber

c) material testing- tensile test

10) underground fiber optic cables- a) material properties- high fatigue strenght, zero stress aging

b)material used- layers of acrylate polymer

c) material testing- visual inspection for any fault

11) pratective sheath for underground cables- a) material properties- resistance to environmental stress

b)material used- lead, PVC

c) material testing- checking for insulation and water penetration