Discuss in detail composition characteristics and properties
To achieve the criteria the evidence must show that the student is able to:
- Detail the appropriate properties and criteria for the selection of a metallic, ceramic, polymer and composite material
- Explain the particular characteristics related to the microstructure and macroscopic behaviour of the four categories of engineering materials
- Generate and process test data to assess material properties for two categories of material
- Investigate and assess the quality of suitable data from three different sources
Assignment Brief –
Purpose of this assignment
To identify the characteristics of materials to ascertain their suitability for a given use or process.
To be able to select and use test equipment to measure a range of materials, and apply the data to determine the suitability of said materials for a specific task.
To use primary and secondary sources of information to produce a considered, and reasoned decision for the selection of a material for a specific task.
Material Selection is cyclic in nature, with the balance between service, manufacturing and economic requirements trying to be met. With the vast amount of materials now used, it is possible to manufacture components that fulfil many service requirements. The properties of a particular material may also be altered by heat treatment, cold working, or by changing the alloying composition etc.
Example; A bolt is made from a particular material, because it is perhaps known to be hard, unfortunately it may also be difficult to produce. When this bolt is put into service it lasts way beyond its expected duty, and therefore may need modifying. It could encourage a change in the material, make it from a softer metal, perhaps making it easier to manufacture, and thereby reducing the cost. This spiral could continue until failure means returning to using a harder material.
By testing materials engineers can learn how materials behave under differing service conditions; the results of this testing can help the design team when selecting a suitable material.
Task 1 – Detail the primary factors and to be considered and process to be followed when selecting materials.
Task 2 – Research and identify some of the different materials that are used in the manufacture of modern motor vehicles. For each material identified you should state the component, where it is on the motor vehicle, the primary material selection criteria, and into which of the groups below it fits.
i. 6 metallic materials (3 used in the engine/gearbox & 3 metallic materials used elsewhere on the motor vehicle)
ii. 2 ceramic materials
iii. 2 composite materials
iv. 4 polymer materials
v. 1 smart material (this may be from a developmental perspective)
This selection will provide the content required to undertake Task 3
Task 3 – From the components you have identified in section 2 you are required to discuss in detail the composition (inc macro/microstructure), characteristics, properties and manufacturing methods (including how these may affect the properties of the component) used to produce one component from the metallic, ceramic, polymer and composite group respectively. (Approximately 500 words each plus diagrams, images and quotes).
Task 4 – Work in a group to carry out mechanical tests on a selection of materials. You are the required to in around 1000 words produce, a full illustrative description of each of the tests and process your results/data and present them in a suitable form. The tests to be carried out are to include the following.
a) Hounsfield tensile test.
b) Jonomy end quench test.
Task 5 – Using data sources including your test results from task 4, published BS/EN standards for steels and data tables sourced from text books or steel manufacturers guidance, assess the quality of the data obtained and apply this information to suggest a suitable ferrous material which could be heat treated and used as a steel support pin which requires a hardness value of HRC32 and a ultimate tensile strength in the range of 850 – 1000 N/mm2.
Sources of Information
Essential Texts – Higgins R.A. – Materials for Engineers and Technicians (Newnes) ISBN 0750668504
Supplementary Reading – Davis – The Science and Practice of Welding vol 1 – 10th Ed. (Cambridge 1992) ISBN 052143565.
Benham P – Mechanics of Engineering Materials (Longman, 1997) ISBN 058231867X
Higgins – Properties of Engineering Materials 2nd Ed (Arnold, 1997) ISBN 0340700521
Kalpakjian S – Manufacturing Processes for Engineering Materials (Pearson, 2002) ISBN 0130408719
Timings R L – Engineering Materials (vol 2) – 2nd Ed (Longman, 2000) ISBN 0582404665