Engineers design and make things. Let’s assume we’re talking about engineering
components. These components are made of MATERIALS (metal, plastic, ceramic,
composite etc.). The best material from which to make any given component depends
on a number of factors (e.g. mechanical, thermal or electrical properties, density, cost,
environmental impact etc.) and the process by which the final material is chosen is
MATERIALS SELECTION. It is incumbent on engineers to understand how the
various mechanical properties are measured and what these properties represent; they
may be called upon to design structures/components using predetermined materials
such that unacceptable levels of deformation and/or failure will not occur. We
demonstrate this procedure with respect to the design of a tensile-test. In the
processing/structure/properties/performance scheme, reasons for studying mechanical
properties of metals are as follows:
Components made of metal alloys that are exposed to external stresses and forces must
be processed so as to have appropriate levels of mechanical characteristics (i.e.,
stiffness, strength, ductility, and toughness). Thus, it is essential that the designer or
engineer understand the significance of these properties, and, in addition, develop a
sense of perspective as to acceptable magnitudes of property values.
Tasks 1 and 2.
In tasks 3 and 4, we use a well-established graphical methodology for materials
selection based on quantitative measures of performance called PERFORMANCE
INDICES. This methodology is the one employed within the CES 2020software – and
part of the aim of this assignment is that you become familiar with the use of this
software. You will be using it in all 3 years of your degree.

1. Mechanical Properties of Materials (Stress-Strain diagram)
   Many materials, when in service, are subjected to forces or loads; examples include the
   aluminium alloy from which an airplane wing is constructed and the steel in an
   automobile axle. In such situations it is necessary to know the characteristics of the
   material and to design the member from which it is made such that any resulting
   deformation will not be excessive and fracture will not occur. The mechanical
   behaviour of a material reflects the relationship between its response of deformation to
   an applied load or force. Key mechanical design properties are stiffness, strength,
   hardness, ductility, and toughness.
   TASK 1 (30%)
   1.1 Using data provided on the Excel sheet plot force / displacement graph for each
   metal.
   1.2 Using the data and formula provided, calculate stress and strain and plot stressstrain diagram for each metal.
   Stress
   σ = F / A
   σ is the engineering stress in (MPa)
   F is the force in (KN)
   A is the cross sectional area of the sample = πd²/ 4
   Strain
   Ɛ = (lf – l0) / l0
   Ɛ is the engineering strain (no unit)
   l0 is the original length of the sample in (mm)
   lf is the final length of the sample in (mm)
   1.3 Show the yield, UTS and breaking stress on the diagram for each metal.
   1.4 Calculate young’s modulus for each metal.
   1.5 Calculate % Elongation and % Reduction in area for each metal.
   % EL = (lf – l0) / l0 % RA = (A0 – Af) / A0
   1.6 Explain and compare metals behaviour in terms of strength, ductility and stiffness.
   (200 words)
2. Influence of heat treatment on the microstructure and mechanical properties of
   steels
   Conventional heat treatment procedures for producing martensitic steels ordinarily
   involve continuous and rapid cooling of an austenitised specimen in some type of
   quenching medium, such as water, oil, or air. The optimum properties of a steel that has
   been quenched and then tempered can be realized only if, during the quenching heat
   treatment, the specimen has been converted to a high content of martensite; the
   formation of any pearlite and/or bainite will result in other than the best combination
   of mechanical characteristics. During the quenching treatment, it is impossible to cool
   the specimen at a uniform rate throughout—the surface will always cool more rapidly
   than interior regions. Therefore, the austenite will transform over a range of
   temperatures, yielding a possible variation of microstructure and properties with
   position within a specimen.
   TASK 2 (20%)
   Using ‘Iron Carbon Equilibrium Diagram’ Figure 1 below, explain the effect of addition
   of Carbon to Iron in terms of critical temperature lines, microstructure and mechanical
   properties. Also with the aid of the phase diagram compare the effect of annealing,
   normalising and water quenching heat treatment processes on the microstructure,
   strength, hardness and toughness of a 0.4 plain carbon steel. (250 words)
   Figure 1: Iron Carbon Equilibrium Diagram
3. Materials and Manufacturing Process Selection
   3.1 Materials Selection Charts
   A materials selection chart is a 2-D plot of one material property (or combination of
   properties) against another. A simple example might be a plot of Young’s Modulus (yaxis) v Density (x-axis). Such a plot can be generated via CES (Figure 1):
   Figure 2. Young’s Modulus -v- Density Materials Selection Chart.
   Any given unique material would occupy a single point on the above chart. Because a
   material such as cast iron or PVC is, in reality, a family of materials, then it occupies a
   “bubble” or “island” on the chart as indicated in Figure 2 above.
   TASK 3 (30%)
   Work individually to research and select the material and manufacturing method of one
   of the following parts below. Use CES software compare materials that are most
   suitable for the chosen component and suggest one material and a manufacturing
   process to build the part from the selected material. Your analysis should be based on
   the structure/property/processing/ performance and also involve cost-benefit analysis
   and quality control of such process with sustainability in mind. (300 words)
4. Connecting Rod
5. Jet Engine Gas Turbine Blade
6. Ceramic Cores
7. Electric Socket
8. Drink Bottles
9. Tennis Racket
10. Internal Combustion Engine Block
11. Electric Motors
12. Robot Arm
13. Hip Implant
    Density (kg/m^3)
    10 100 1000 10000 Young’s modulus (GPa)
    1e-4
    0.001
    0.01
    0.1
    1
    10
    100
    1000
    Rigid Polymer Foam (MD)
    Softwood: pine, along grain
    CFRP, epoxy matrix (isotropic)
    Polyvinylchloride (tpPVC)
    Cast iron, gray
    Young’s Modulus v Density (Level 2 Database)
    Task 4 (20%)
    Work individually using CES or any other reliable source to research and select the
    material and manufacturing method of one of the following parts below. Compare
    materials that are most suitable for the chosen component and suggest one material and
    a manufacturing process to build the part from the selected material. Your analysis
    should be based on NHS requirement for the PPEs to avoid Corona virus (COVID-19)
    contamination and infection. (300 words)
    NHS requirements for PPE:
14. Masks
15. Overalls
16. Filters
17. Ventilators
18. Gloves
19. other (see guidance)
    See the Uniforms and work wear: guidance for NHS employers
    file:///C:/Users/ue0mgr/Desktop/COVID-19/Uniforms-and-Workwear-Guidance-2-April2020%20(1).pdf
    Harvard Referencing and Citation should be used within the report.
    For Guidance:
    http://library.sunderland.ac.uk/find-resources/referencing/
    https://my.sunderland.ac.uk/pages/viewpage.action?spaceKey=AQH&title=Program
    me+Regulations+and+Assessment&preview=/105484811/106738782/Guidance%20f
    or%20students%20on%20the%20penalty%20for%20exceeding%20the%20limit%20f
    or%20assessed%20work%20v2.pdf