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The University of Newcastle

School of EngineeringMECH3400 Materials Science and Engineering 2

Materials Selection Assignment - 2013

The rational and optimal selection of materials underpins all engineering endeavours. In individual

tutorials and class exams, you will practice various aspects of the materials selection process as

follows:

i) defining a component function statement;

ii) identification of constraints;

iii) analysis of the relative importance of functions and constraints;

iv) translating these to material properties;

v) conducting coarse screening using constraints (or limits);

vi) derivation of one or more materials indices;

vii) short-listing materials using 2-d charts and selection lines etc;

viii) ranking short-listed materials using other methods including multi-objective analysis;

ix) consideration of the influence of shape and x) more detailed investigation of individual materials and their properties.

In this assignment, you will integrate all  of these steps to conduct a complete and thorough

selection of a material for an application – in fact the above list can be a rough template for

completing the assignment. Some of the tutorial exercises will be directly relevant to your

assignment (so you should save them) and others indirectly (i.e. the method will be valuable but the

specific example will be different). The assignment (hard copy and electronic copy through

Turnitin) is due by 5pm on Monday 3rd

 June 2013. The assignment is worth 15% of your overall

mark for the Course. You are strongly advised to work steadily on the assignment each week as

each topic is covered in the lectures and tutorials. You will not be able to complete it

satisfactorily in the last week. 

This is an individual assignment i.e. the submitted work is to be the work of an individual student.

However, as the components you will be allocated are part of a larger system assigned to your

laboratory group, a top-notch solution will be expected to include a small section at the end of the

assignment addressing how your component integrates with the rest of the system and summarising

its overall attributes (primarily cost and mass) which will require you to share some information

with other group members. If you wish, you can work on your assignment at the same time as other

members of your group, recalling that the submitted work needs to be your own. You will be

required to submit a Turnitin similarity report with the hard copy of the assignment.

The systems under study will be internal combustion engines of 6 different types. For convenience

one will be assigned to each laboratory group. Each student in each laboratory group will have adifferent component(s) to analyse and select materials for. As such, no two students will have

exactly the same task to complete.

The 6 different engines and group allocations are:

i) A 4-stroke motor mower engine Group 1

ii) A 4-stroke engine for a family motor car Group 2

iii) A diesel engine for a family or touring car Group 3

iv) A line trimmer engine (‘Whipper Snipper’ or similar) Group 4

v) A formula 1 racing car engine Group 5

vi) A sports motor cycle engine (2 or 4 stroke optional) Group 6

The components available for analysis are:

i) The piston(s)

ii) The connecting rod(s)

8/11/2019 Materials Selection - Car Engine head

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iii) The crankshaft

iv) The engine block and oil sump

v) The engine head

vi) The valves and camshaft(s)

vii) The inlet and outlet manifolds

viii) The fan and pulley(s)

ix) Big-end and little end bearingsEach group will need to meet and decide which component each member will work on. I suggest a

random ballot if there is disagreement. Next week I will circulate a sheet in class on which you can

indicate the component you have taken.

In order to complete the assignment you are urged to search out references concerning the design of

engines as well as the general requirements for the type of engine you have been given. You can use

our library holdings, the interlibrary loan service or try internet book sellers for a second hand copy

(Amazon or Abe books are two well known ones). Reference books on machine design will help

you identify the load case(s) for your component(s) on your kind of engine and the most important

function (and hence properties) although later we will study multi-objective analysis and I will

expect a good assignment to use those methods so keep that in mind. A search on ENGINE

DESIGN using Google gives a plethora of web-sites on the subject: many interesting (some not so

useful).

Are you thinking “so what do I do now”? 

My suggestion is: START NOW!

i) Decide quickly which component is yours

ii) Get hold of some reading and analyse the load situations (you don’t need exact forces here!)iii) Note any assumptions at the beginning

iv) Using the list in italics in the first paragraph on p1 as a guide, start working.

v) Don’t be overly influenced by engines you have owned or seen and the materials they are

made from. Be objective and wait until you have finished your own analysis. Then compare

with materials currently used.

Assessment

Document each stage of your selection process in a word-processed report using 12 point Times-

Roman or similar font with maximum 2.5cm margins, hopefully not exceeding 15 pages in length.

It should end with a final recommendation as to the material to be used and how it is to be shaped(at least to CES level 3 accuracy, hopefully better) and contain a summary at the front. Include all

working and justification for your choice (derivation of material indices, calculations, copies of

graphs with limit and selection lines in place, property tables, decision tables or trees etc…).

 Longish derivations or calculations can be placed in appendices and can be hand-written – no

 need to waste time typesetting equations and calculations.