Mechanical and Aeronautical Engineering MSc Programme

Module name:	Structural Integrity: Design against Failure
Module code:
Title of the Assignment:	Critical Failure Analysis Assignment
This coursework item is: (delete as appropriate)	Summative	Formative
This summative coursework will be marked anonymously	Yes	No
The learning outcomes that are assessed by this coursework are: LO 1: Interference between the applied stress and strength of the materials in the design stages. [Report, assignment 1] [IMechE: SM7M, EA7M, EL10M, P9, P12, G3m] LO 2: Describe the response of the engineering components – within the microstructural scale – to the external factors such as stress, humidity, light, temperature, and radiation. [Report, assignment 1]
This coursework is: (delete as appropriate)	Individual	Group
If other or a mixed … explain here:
This coursework constitutes 50% to the overall module mark.
Date Set:
Date & Time Due:
The ‘normal’ coursework return date for this work is:	Up to 20 working days after submission
When completed you are required to submit your coursework to: , via TurnItIn link within the Module Blackboard Shells
Late submission of coursework policy: Late submissions will be processed in accordance with current University regulations which state: “The time period during which a student may submit a piece of work late without authorisation and have the work capped at 50% if passed is 14 calendar days. Work submitted unauthorised more than 14 calendar days after the original submission date will receive a mark of 0%. These regulations apply to a student’s first attempt at coursework. Work submitted late without authorisation which constitutes reassessment of a previously failed piece of coursework will always receive a mark of 0%.”
Academic Offences and Bad Academic Practices: These include plagiarism, cheating, collusion, copying work and reuse of your own work, poor referencing or passing off of somebody else’s ideas as your own. If you are in any doubt about what constitutes an academic offense or bad academic practice you must check with your tutor.

Type of assessment Component Marks Date Set Date Due Date Return Lab report – 500 words maximum 15%   Presentation 10-15 minutes 15% Complete all the exercises all the required graphs, tables, calculations, and appendices. 2000 words maximum. 70% Total 100% Remarks: All works are individuals, summative and not anonymously marked.

Tasks to be undertaken: See coursework descriptions below This assessment Weightings 50% of the whole module

Lecture sessions and seminars

The failure analysis assignment will be supported by weekly lectures, and seminars, as well as lab sessions whenever required, to work on various parts of the assignment. Students can also seek advice on various aspects of their work, e.g. comments on proposed methods/approaches; advice on sources of information; etc.

Scope

Designing machines, vehicles and structures that are safe, reliable, and economical requires both efficient use materials and assurance that structural failure will not occur. Therefore, this module is appropriate for postgraduate students to study the mechanical behaviour of materials, specifically for topics such as fracture, fatigue, creep and corrosion. Structural Integrity: Design against Failure module covers topics such as types of materials and their properties and types of failure in materials. It also focuses on stress-based fatigue analysis, relatively new methods of fracture mechanics, creep, and corrosion resistance.

Structural Integrity: Design against Failure Coursework One

Note:

This coursework includes three major parts, lab report, presentation, and exercises. All parts need to be submitted as one file. Presentation slides will be inserted to the word file, through Turntin.

Part 1 – Lab Report (15%) Maximum 500 Words

The following data of load (kN) vs. the gauge length (mm) is given for a tensile test sample, dimeter 12 mm and length 50 mm. Calculate, plot the engineering stress vs. engineering strain curve and extract, at least, five mechanical properties of the material under consideration.

Load	0.00	3.05	4.30	7.40	14.00	20.10	24.50	29.50	34.50
Length	50.00	50.10	50.15	50.25	50.45	50.60	50.71	50.90	51.05

39.00	41.50	44.70	46.15	47.25	47.46	46.00	44.70	42.50	36.16
51.31	51.80	52.83	53.84	54.86	55.88	56.80	57.60	58.40	58.80

Note: the report should include the theory part, calculations, discussion, and references.

Part 2 – Presentation (15%)

Preparing 7-10 minutes presentation to investigate a case study failure (of your choice), showing the reasons behind the failure and the precautions that had to be done to avoid the failure, in terms of materials selection, design, service conditions and environment.

Part 3 – Exercises

Exercise 1 – Crack Initiation

Highlight the main reasons behind developing microcracks near a base of steel shaft radiator fan blades, with listing ways that may help to stop growing the cracks.

Maximum 300 Words                                                                                                          10%

Exercise 2 – Thermal Stresses

FR4 is a class of glass fiber epoxy laminate used in manufacturing printed circuit boards. Discuss the role of the coefficient of thermal expansion between the substrate and silicon, e.g. flip chips, within the electronics packaging point of view.

Maximum 300 Words                                                                                                           10%

Exercise 3 – Mechanical Metallurgy Effects

In a lab, the available resources are different metallic alloys, electrical oven reaches 2000^oC, different cooling solutions, testing machines of tensile, hardness, fatigue and corrosion. Prepare an appropriate material, after applying heat treatments, to make a cutting tool for a vibrating hammer used to crush mine rocks. Give reasons for each suggested steps and heat treatments.

Maximum 300 Words                                                                                                           10%

Exercise 4 – Low-Temperature Applications

You are an engineer designing a pressure vessel to hold liquid nitrogen. What general characteristics should the material have to be used for this application? Out of the various types of mechanical tests described in this module, describe the test(s) that aid in selecting an appropriate material? Showing the reasons for each chosen test/material.

Maximum 300 Words                                                                                                        10%

Exercise 5 – Fatigue Life

A simply supported rotating shaft, loaded by a force 9 kN, made by machining from a low alloys steel with σu = 700 MPa, and σy = 500 MPa. Analyse the shaft and conclude some useful results. Estimate and comment on the life of the shaft.

All dimensions in mm

Maximum 500 Words                                                                                                          15%

Exercise 6 – Design based on Materials Properties

A cantilever beam with a length 100 mm is exposed to a bending force of 200 N at the free end.

Perform the selection of the material for minimum mass and minimum weight design of stiff ties; based on the properties given in the table below.

Calculate the beam radius r that is required for each material. Assume factor of safety

= 2.

Compare and rank the materials based on relative criteria you think need to be considered.

Material Type	Example (Standard)	E (GPa)	Strength (MPa)	Density (g/cm3)	Relative cost
Mild Steel	AISI 1020	203	260	7.9	1
Low      Alloy Steel	AISI 4340	207	1103	7.9	3
High Strength Al Alloy	7075-T6 Al	71	469	2.7	6
Titanium Alloy	Ti-6Al-4V	117	1185	4.5	45
Polymer	Polycarbonate	2.4	62	1.2	5
Wood	Loblolly pine	12.3	88	0.51	1.5
Economical Composite	Glass,             cloth   in epoxy (GFRP)	21	380	2.0	10
High Performance Composite	Graphite fibre in epoxy laminate (CFRP)	76	930	1.6	200

Maximum 500 Words                                                                                                           15%

Guidelines for writing in general: 5Cs – Clear, Concise, Complete, technically Correct, Critical analysis.

All references must be appropriately indicated within the text and will be listed at the end of the coursework.

Use Turnitin to submit the assignment.

Recommended Reading list:

1. Jorge Luis González-Velázquez, Mechanical Behaviour and Fracture of Engineering Materials.

• Kannadi Balan, Metallurgical Failure Analysis.

• J. Rösler, Mechanical Behaviour of Engineering Materials.

• Norman Dowling, Mechanical Behavior of Materials.

• Richard W. Hertzberg, Deformation and Fracture Mechanics of Engineering Materials.

• Fontana and Green, Corrosion Engineering.

• Serope Kalpakjian, Manufacturing Processes for Engineering Materials.

• John C. Lippold, Welding Matellurgy and Weldbility, 2015, Wiley.