Visualizing Material Properties in the Classroom

Transcription

1 Visualizing Material Properties in the Classroom Compiled by Elisabeth Kahlmeyer and Claes Fredriksson from slides created by Mike Ashby M. F. Ashby, 2015 For reproduction guidance see back page This lecture unit is part of a set created by Mike Ashby to help introduce students to materials, processes and rational selection. The Teaching Resources website aims to support teaching of materials-related courses in Design, Engineering and Science. Resources come in various formats and are aimed primarily at undergraduate education. Some of the resources are open access and students can access them. Others are only available to educators using CES EduPack.

2 Content, Objectives, Resources Contents of this package: 20 slides on materials and properties 1 Poster slide: Evolution of Materials Suggested questions for Poster included in the Notes of the slide Practical exercise to create your own materials library Learning Objectives Ability to understand the concept of Material properties Ability to understand relationships between different materials Ability to interpret and understand Material property charts Resources used at Universities for working with material properties Granta s Teaching Resources Website: High_Schools_and_Community_Colleges Software: CES EduPack (grantadesign.com/education)

3 Materials are important everywhere Wood Polystyrene / Polycarbonate CFRP ABS Plastic MATERIALS AND PROPERTIES Industry Schools Vocational Education Universities Research Mike Ashby,

4 The expansion of the materials world James Stuart, Professor of Engineering at Cambridge University In his day: A few hundred materials No polymers (now 10,000 s) No light alloys (now several thousand) No composites (now hundreds ) time Lots of interesting new materials to learn about Today: 160,000+ engineering materials

5 Materials use in the World Annual world production

6 Types (Families) of Materials

7 Visualization of material surfaces Images of shapes and surfaces help Metals, alloys Metals, alloys Polymers, elastomers Ceramics, glasses Hybrids, composites

8 Visualization of materials in use Images of applications is also of great utility Metals, alloys Metals, alloys Polymers, elastomers Ceramics, glasses Hybrids, composites Mike Ashby,

9 Visualization of manufacturing processes Primary shaping Injection Molding Secondary shaping Machining Joining Welding Surface treating Painting

10 Material properties are important for function

11 Examples of thermal properties

12 Material properties Polymers: ABS Some Characteristic Polymer properties Flexible (not stiff) Can be strong Temperature-sensitive Easy to shape Corrosion resistant

13 Material properties Metals: Aluminum Some Characteristic Metal Properties High stiffness (Young s modulus) Strong, yet ductile Can be made stronger by alloying or thermo-mechanical processes (hardening) Susceptible to fatigue and corrosion 91 of the 118 elements are metals.

14 Material properties Ceramics: Alumina Some Characteristic Ceramic Properties High stiffness but brittle Stiff, hard Retain strength at high temperatures Resist wear and corrosion Very low electrical and thermal conductivity

15 Material properties Composites: CFRP Some Characteristic Hybrid Properties Combinations of two or more different materials Keep attractive material properties while avoiding drawbacks. Many materials of nature wood, bone, skin, leaf. Fiber-reinforced polymer composites are light, stiff and strong Restricted to below 250 C because the polymer softens. Expensive and relatively difficult to form, join and recycle.

16 Visualizing material properties

17 Material property data Density, Stiffness Name Density Modulus kg/m 3 GPa ABS 1.11e Alumina 3.89e3 366 Aluminum alloys 2.69e Aluminum nitride 3.29e3 324 Bamboo Borosilicate glass 2.25e Brick 1.83e Butyl rubber (IIR) e- 3 Cast iron, duckle (nodular) 7.15e3 172 Cast iron, gray 7.15e3 105 Cellulose polymers (CA) 1.13e CFRP, epoxy matrix 1.55e3 102 Concrete 2.45e Copper alloys 8.94e3 129 Cork e- 3 Epoxies 1.25e Ethyl vinyl acetate (EVA) e- 3 Flexible Foam (LD) e- 3 Flexible Foam (MD) e- 3 Flexible P Foam (VLD) e- 6 GFRP, epoxy matrix 1.86e Gold 19.3e3 79 High carbon steel 7.85e3 207 Name Density Modulus kg/m 3 GPa Ionomer (I) Lead alloys 10.7e Leather Low alloy steel 7.85e3 211 Low carbon steel 7.85e3 207 Magnesium alloys 1.84e Medium carbon steel 7.85e3 208 Natural rubber (NR) e- 3 Nickel alloys 8.89e3 204 Paper and cardboard Phenolics 1.28e Polyamides (Nylons, PA) 1.13e3 2.9 Polycarbonate (PC) 1.17e Polychloroprene 1.24e3 1.18e- 3 Polyester 1.21e P- etheretherketone (PEEK) 1.31e Polyethylene (PE) PE terephthalate 1.34e Polyisoprene rubber (IIR) e- 3 Polymethyl methacrylate 1.19e Polyoxymethylene (POM) 1.41e Polypropylene (PP) Polystyrene (PS) 1.04e Name Density Modulus kg/m 3 GPa Polytetrafluoroethylene 2.17e Polyurethane 1.13e3 7.75e- 3 Polyurethane (tppur) 1.18e Polyvinylchloride (tppvc) 1.43e Rigid Polymer Foam (HD) Rigid Polymer Foam (LD) e- 3 Rigid Polymer Foam (MD) Silica glass 2.19e Silicon 2.32e3 147 Silicon carbide 3.15e3 429 Silicone elastomers (SI, Q) 1.53e3 10e- 3 Silver 10.5e3 71 Soda- lime glass 2.46e3 70 Stainless steel 7.85e3 199 Stone 2.28e Tin 7.27e3 43 Titanium alloys 4.6e3 104 Tungsten alloys 18.7e3 343 Tungsten carbides 15.6e3 661 Wood, typical across grain Wood, typical along grain Zinc alloys 5.89e3 80.4

18 Understanding material properties Why the differences? Atom size, mass and packing determine density Chemical bonds work a bit like springs and determine stiffness Families occupy discrete fields

19 Material selection: high specific stiffness Stiff but heavy Stiff and light Light but not stiff

20 The building block of materials

21 Elements Effect on properties FCC metals are normally very ductile

22 Back to the Historical Perspective Early history 3000 BC The evolution of structural materials

23 Giving Historical Perspective The evolution of structural materials

24 Giving Historical Perspective The evolution of structural materials

25 Giving Historical Perspective The evolution of structural materials

26 Giving Historical Perspective The evolution of structural materials

27 Giving Historical Perspective The evolution of structural materials

28 Additional materials perspectives Food for thought Environment Resources New materials Manufacturing

29 Poster to print out (A3) for exercises

30 Exercise: Build your own Materials Library Ask students to bring small samples from the 3 main material family types: Polymers, Metals, Ceramics (and glasses). Collect the samples and start to organize them into three groups, one for each type. Try to find the material name and label them. Now, you have a nice materials library to display and do activities around. For example to research densities (not weight), prices per weight and if the materials can be recycled. Students can also investigate more advanced properties.

31 Authors Claes Fredriksson, Elisabeth Kahlmeyer Granta Design Ltd. Images created by Professor Mike Ashby, University of Cambridge and Granta Design Reproduction This resource can be reproduced for teaching purposes. Please make sure that Granta Design is credited on any reproduckons. You cannot use these resources for commercial purposes. Accuracy We try hard to make sure these resources are of a high quality. If you have any suggestions for improvements, please contact us by at teachingresources@grantadesign.com There are 300+ resources (Available to Educators) Including: n n n n n n n PowerPoint lecture units Exercises with worked solutions Recorded webinars Posters White Papers Solution Manuals Selection Case Studies M. F. Ashby, 2015 This lecture unit is based on slides by Professor Mike Ashby to help introduce students to materials, processes and rational selection. The Teaching Resources website aims to support teaching of materials-related courses in Design, Engineering and Science. Resources come in various formats and are aimed primarily at undergraduate education. Some of the resources are open access and students can access them. Others are only available to educators using CES EduPack.