代写CAPE1720 – Materials Science and Engineering帮做Python语言程序

CAPE1720 – Materials Science and Engineering

ASSESSED COURSEWORK: MATERIALS SELECTION ASSIGNMENT (RESIT)

INTRODUCTION

The end of Semester 1 introduced the concept of materials selection  in product design. Materials selection is an essential technique for engineers developing components for products in addition to choices about materials processing routes. Materials processing was also introduced more fully in Semester 2 but does not form a central focus of this assignment. This assignment focuses specifically on the method of systematically refining a set of candidate materials for a component of particular product.

Historically, intricate and long-studied expert knowledge of many materials was used to arrive at a choice of the materials for making things. Here, our attention is on a systematic method termed the Ashby method. This method is based on first identifying, in general terms, performance requirements and priorities. These requirements are then translated into equations which can be used to identify a particular figure of merit or performance index to screen (filter) and rank materials in a database. Fortunately, while products are highly varied, the equations and indices used can be boiled down to a finite set. This assignment will ask you to identify appropriate indices and apply these within a software database (Ansys EduPack.,

THE RESIT ASSIGNMENT

The resit coursework on materials selection must be carried out individually. You are free to discuss generic topics with your peers, but the report (and all its content) must be your own work. The report should be completed using the template on Minerva, provided within“Assessment and Feedback”in the folder titled“Semester 2 一 Materials Selection Assignment (August 2025 Resit)”. The template also outlines the sections required (see also key elements below as well as definitions in Appendix 1 and marking criteria in Appendix 2).

For the resit assignment, you are required to consider a single product:             Aircraft jet engine

You are free to choose which type of aircraft jet engine. Making a specific a choice is recommended to guide the materials selection stages (e.g. constraints). The selected type must include the following two components:

a.    Fan blade

b.    Compressor shaft

You are required to carry out materials selection for both components.

Remember there is no single correct answer to this assignment. It is possible to score well with one of a variety   of solutions provided you offer a well-reasoned justification for your materials criteria and selections. If for any  reason you do not have access to Ansys EduPack, please also note that it is possible to produce a fully acceptable   soIution to this probIem using the pubIished charts (“EduPack 一 Selected Materials and Process Selection Charts” in“Materials Selection Software Reference”within the“Learning Resources: Semester 2 一 Materials Selection” heading on Minerva). Finally, carefully consider the safety-critical nature of the components and the need to  tolerate damage. You may wish to use a minimum fracture toughness as a primary constraint as this can rule  out  materials with  unacceptably  low toughness. A  (rule  of thumb,  used  by  Mechanical  Engineers  for the   appropriate value of fracture toughness is discussed in Unit 3 of the EduPack self-learning module on Minerva.

DEADLINE AND SUBMISSION

The report is due by 2:00 PM on 11 August 2025. Marks will be shared in line with the release of resit marks across the School. The submission should be completed on Minerva through the TurnItIn submission point   within the Assessment and Feedback section under Submit my work. The submission point is titled

“Coursework Resit Submission (August 2025): Materials Selection Assignment”.

All submissions will be checked via Turnitin and charts as well as text will be reviewed during marking to check for collusion or plagiarism. All parts of the resit assignment are to be carried out individually and to be your work alone. There is no standalone academic integrity form. for this assignment as the individual submission will be taken to confirm that the work is your own.

KEY ELEMENTS OF THE ASSIGNMENT (ALL INDIVDIUAL)

Stage 1

Report sections: (1) Description & design requirements, (2) Identification of components and their loading geometry

•     Write a concise description of your product - what does it do?

•     Specify performance requirements of the product as a whole

•     Sketch a representation of your product with text/numerical annotations

•     Write a brief accompanying paragraph describing the components in the sketch

Stage 2 (To be carried out for both components, separated in sections component-by-component 一 see template) Report sections: (3) Specification of performance requirements at component level, (4) Design translation at the component level,  (5) Materials indices based on  the design  translation,  (6) Screening  materials  using primary constraints in Ansys EduPack, (7) Selection of the optimal material using materials indices in Ansys EduPack

•     Specify performance requirements for each of the two components

•     Analyse the objective, function, constraints, and free variables in the design for each component

•     Choose appropriate materials indices for each component

•     Carry out screening and ranking processes in EduPack software for each component

•     Show graphs and write accompanying paragraph text to describe the process you have used in each case (and thereby provide evidence of your approach to analyse the selection problem and carry out materials selection using Ansys EduPack).

•     Select the optimal material for each component using EduPack software and write a justification of the choice

Stage 3

Report components and marking criteria: (8) Discussion of the limitations of the materials selection process,

(9)  Discussion  of the  validity  of the materials selection  and comparison  with  materials currently  used for the components, (10) Presentation, (11) References

•     Write a conclusion with a final recommendation on materials for the two components of the jet engine

•     Write a discussion of the reliability of these selections

•     Write a comparison of these to materials used commercially for similar products

•      Include appropriate and consistent referencing 一 all sources must be referenced and cited in the text

•     Check the report for high quality presentation of figures, figure captions, sectioning, and referencing

As a guideline, it should not be necessary for your individual report to exceed 1,750 words in length. Inclusion of material not relevant to the materials selection process will be penalized, and conciseness will be rewarded.

SUPPORT

A.  Semester 2 lectures: Three lecture sessions at the start of Semester 2 were devoted to working through the Ashby method and the use of Ansys EduPack. Lecture capture recordings are available on Minerva.

B.  Three online self-learning (Units 1-3) are available to go into further detail on using EduPack software.

C.  A worked example is available on Minerva. Note, the worked example includes only 4 components and is presented (section-by-section., The sections shouId be (component-by-component, in the report. The resit assignment is entirely an individual assignment.

D.  The textbook Materials Selection in Mechanical Design by Mike Ashby (available electronically via the library website) presents further useful information and examples.

For questions on the resit assignment, please get in touch by email ([email protected]).

APPENDIX 1: RECAP OF THE MATERIALS SELECTION METHOD

Description & design requirements: Describe the overall functional system and its design requirements, i.e. the things that this assembly has to do effectively.

Identification of components and their loading geometry:  Present a diagram or annotated image to clearly indicate the overall design, the specified components (dimensioned where relevant) and their position in the assembly. Describe the geometry of the loading that will act upon each component in service.

Specification of performance requirements at the component level: Estimate performance requirements, i.e. some reasonabIe vaIues of each component’s Ioads (where these can be estimated) or service environment, (e.g.  operating temperature,  pressure,  speeds).  What  materials  properties  are  therefore  required?  What dimensions (length, diameter, etc.) of the components are constrained by the design? What failure modes may apply? You may spend some time reading about the product, but please note that researching the product is not the aim of this assignment. A reasonable estimate that can be referenced or justified otherwise is sufficient. Often,  identifying  which  performance  requirements  are  most  important  is  the  most  useful  rather than identifying a single numerical value. Keep requirements loose initially to ensure plenty of candidate materials can be identified and tighten the requirements as you screen and rank to identify an optimal material.

Design translation at the component level: Translate the performance requirements into function, objective, constraints, and free variables for each component by defining what objectives (e.g.  minimised cost) and constraints (e.g. design-prescribed length, the temperature it needs to tolerate as a minimum) apply to each component. These will be used to look up appropriate materials indices and to define primary constraints. Review the tables of materials indices (appendix of Unit 3 and on Minerva) to help in identifying appropriate objectives, constraints and free variables.

Materials indices based on the design translation:  Using the defined function, objective, and free variables for each component, you can now identify a list of primary constraints (where there is a defined limit arising from the design translation) and ideally one (or perhaps two at most) appropriate materials index/indices, which will be  used  in  screening  and  ranking  the  material(s), respectively. In many  applications,  toughness is  a key consideration; applying a minimum (rule of thumb’fracture toughness (see also self-learning module Unit 3) as a primary constraint can rule out materials with unacceptably low toughness.

Screening materials using primary constraints in Ansys EduPack: The primary constraints defined above will then allow you to use Ansys EduPack to screen-out materials which cannot do the job, e.g. materials that cannot operate at a sufficiently high temperature. You need to choose which selection method (tree, limit, or graph) is best suited to each of these stages for each of the components. For the maximum operating temperature, consider whether the component can be cooled. Be sure to include evidence or justification for selecting limit stages with mechanical property values.

Selection of the optimal material using materials indices in Ansys  EduPack: Appropriate materials indices, defined above, will enable you to use Ansys EduPack to rank those materials which survive screening in order of how well they meet one/perhaps two materials index/indices to determine which material can best do the job. This will leave you with a shortlist of materials for that component and you can then complete your analysis by using your judgement to say which material on your shortlist might be the most appropriate; other constraints (where no limit is specified) may also now be considered during this final selection stage, e.g. by using a bar chart to rank them against another constraining property such as fracture toughness, corrosion resistance, fatigue limit or price.

Discussion of the limitations of the materials selection process: Say whether there are other factors that Ansys Edupack does not take into account (e.g. fatigue, creep, corrosion?) and thus what are the limitations of the approach used. Some key limitations are that high temperature performance is not covered in detail, durability is general and not condition specific (including friction and wear) and fatigue is not component specific.

Discussion of the validity of the materials selection and comparison with materials currently used for the components: Comment on how different (or similar) your selection is to materials that are currently used for that component and how valid your selection is based upon material sources from the lectures, from literature and/or from web sites.

APPENDIX 2 : MARKING CRITERIA

The table below shows the weightings for each section of the report and what would be required to gain maximum marks under each of these headings. Each section will receive a mark out of the maximum number available in the section. All sections are required and should be completed individually for this resit assignment for both of the components (fan blade and compressor shaft) for an aircraft jet engine.

Section	Complete Answer	Marks
Description and Design Requirements	A complete description of the components and all relevant design requirements. No irrelevant requirements are included and there are no errors.	5
Identification of Components and their Loading	A high-quality sketch, with dimensions given in the annotation or text where possible, is presented. The sketch gives a clear indication of the overall design,   the specified components, and their position in the assembly. The loading for all components has been carefully analysed. There are no omissions or errors, and  no irrelevant material has been included. A concise written description of the sketch is included.	5
Specification of performance requirements at the component level	An excellent analysis of the design and performance specifications, considering the time available. An excellent description of operating parameters (where possible) and dimensions, where these are constrained, has been included and    the failure modes have been considered. The reasoning is sound and critical. The methods have been carefully and accurately followed. No important points are    omitted. No irrelevant points have been included and there are no errors.	20
Design translation at the component level	An excellent and accurate translation of the component design and performance requirements into function, objective, constraints and free variables. The reasoning is sound and critical, and the method has been carefully and accurately followed.	20
Materials indices based on the design translation	The design translation for each component has been used to correctly ascribe   materials indices to maximise the performance of each component. All relevant materials indices have been found, and no irrelevant or unimportant indices have been included.	5
Screening materials using primary constraints in Ansys EduPack	Demonstrates fluent understanding of, and competence in, the use of Ansys EduPack for materials screening on the basis of primary constraints.	10
Selection of the optimal material using materials indices in Ansys    EduPack	Demonstrates fluent understanding of, and competence in, the use of Ansys EduPack for materials optimisation using materials indices.	15
Discussion of the limitations of the materials selection process	An excellent critical analysis, considering the time available, across all the required areas and which demonstrates a clear understanding of the content of the lecture course and how this bears on relevant limitations of selection using  Ansys EduPack.	5
Discussion of the validity of the materials selection and comparison with materials currently used for the components	Discussion of the results of the selection process is excellent and critical with respect to material sources from the lectures, from literature, or from online sources	5
Presentation	Outstanding: the presentation is excellent, the format adheres to the template. The figures and tables are captioned and referenced/cited where necessary in   the text. Writing is organised and conveys descriptions and reasoning clearly.	5
References	An appropriately wide range of references have been consulted. The reference list is complete and correctly presented in consistent and complete style (e.g. Leeds numeric or similar). All sources are correctly cited in the text. A good set   of references would typically be expected to be drawn from a variety of sources (e.g. books, articles, technical papers, industry reports, university or professional organisation websites) and should typically comprise no more than ca. 20% unverified internet sources (e.g. Wikipedia).	5