Materials Selection

University of Queensland

Course Description

  • Course Name

    Materials Selection

  • Host University

    University of Queensland

  • Location

    Brisbane, Australia

  • Area of Study

    Mechanical Engineering

  • Language Level

    Taught In English

  • Prerequisites

    MATE1000 or ENGG1200

  • Course Level Recommendations

    Upper

    ISA offers course level recommendations in an effort to facilitate the determination of course levels by credential evaluators.We advice each institution to have their own credentials evaluator make the final decision regrading course levels.

    Hours & Credits

  • Host University Units

    2
  • Recommended U.S. Semester Credits
    4
  • Recommended U.S. Quarter Units
    6
  • Overview

    Course Description
    Principles & practice of materials selection in mechanical design. Influence of shape on selection. Economic aspects. Use of data sources. Material indices. Generation & use of material selection charts. Selection of fabrication method. Concurrent and compound objectives. Selection of materials for a practical application (project).

     

    Course Introduction
    This course is about Engineering Design as much as it is about Materials Selection. The main goal is to learn how to select materials, using the Materials Indices method, as an integral part of the engineering design process.  Traditional methods of Materials Selection rely on extensive use of tables of material properties and past experience, and therefore are largely empirical. On the contrary, the Material Indices method is a rational approach which identifies the combination of material properties that maximises the  engineering (mechanical, thermal, optical, etc.) performance in a given (structural, thermal, optical, etc.) application. For example, the material which minimises the mass of a tie rod of given stiffness, loaded in tension, is the one with the largest value of the elastic modulus/density ratio. This ratio is called the Material Index for the tie rod. It allows ranking the candidate materials, i.e., the most suitable material for the application is the one that gives you the largest number of GPa per kg, or the largest Index.
     
    The material selection done in this way is based on mathematical criteria and therefore it is unambiguous. The method allows selecting materials for structural applications incorporating shape, as well as material substitutions while meeting multiple and/or conflicting constraints (example, finding materials which are cheap but also light). Emphasis is put onto structural applications, but examples involving physical properties, such as optical and thermal properties, are considered as well.
     
    The course consists of a series of lectures to introduce the selection method and a number of question-sets whose resolution during the Tutorial Sessions accounts for a large share of the final marks. The Tutorial Exercises are solved with the help of a dedicated software package, CES 2017 Edupack, (Cambridge Engineering Selector) available in 50/N301, (Computer Lab), Hawken Building for the tutorials, and in all computer labs across the School for work at all times. A laboratory project aimed at familiarising the student with the analysis of raw material data is part of the course as well.

     

    Learning Objectives
    After successfully completing this course you should be able to:

    1. determine Material Indices relevant to a variety of applications; Material index is a combination of material properties that characterises the performance of a material in a given application.
    2. select materials that optimise performance in a given application while meeting external constraints, e.g. material for a beam of given stiffness (strength, toughness… etc.) at minimum mass, cost, size, environmental impact, etc., using the Material Indices approach. Shape is not an issue at this stage.
    3. create and use Materials Selection Charts. These charts are the essential tools of materials selection. They plot a single material property (bar charts), or a combination of properties against another(bubble charts), mapping out the fields in property-space occupied by the material classes.
    4. use Indices which include Shape Factors to rank candidate materials for a given application.Shape Factors: Some shapes are more efficient (i.e., they require less material to do the job) than others in a given application. For example: I-beams are more efficient than solid rods under bending loading. The efficiency of a given shape can be measured by a number, the Shape Factor, which can be incorporated into the Material Index.
    5. identify Multiple Constraints: Most applications involve several, often conflicting, constraints. In order to select the most appropriate material, it is necessary to first identify the active (i.e., the most restrictive) constraint.
    6. apply trade-off analysis using Compound Objectives/Materials Substitution: Almost always a design requires the coupled optimisation of two or more measures of performance, i.e., it has a compound objective. These objectives often collide: e.g. a component may be required to be both cheap and environmentally friendly, and a trade-off is normally required. Likewise, materials substitutions are often required in order to optimise a particular performance and, again, a trade-off may be necessary. These problems are dealt with in a systematic manner by using exchange constants and penalty functions.

Course Disclaimer

Courses and course hours of instruction are subject to change.

Eligibility for courses may be subject to a placement exam and/or pre-requisites.

Some courses may require additional fees.

Credits earned vary according to the policies of the students' home institutions. According to ISA policy and possible visa requirements, students must maintain full-time enrollment status, as determined by their home institutions, for the duration of the program.