Ceramics - inorganic non-metallic materials which lack carbon-hydrogen bonds. Usually metal, non-metal bond.
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What are polymers?
Polymers - high molecular weight, organic compounds. Monomers are joined together.
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What are elastomers, thermoplastics and thermosets?
Elastomers - elastic materials which return to normal after load removed (rubber), thermoplastics - soften when heated, harden on cooling (polypropylene), thermosets - harden on heating (epoxies).
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What is the characterisation process for material selection?
Test, graph test data, then do statistical analysis. Applications determine selection of material.
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What are the steps to finding the material index?
Function - what component does, constraints - hard (non-negotiable), soft - (desirable), Objective - maximise/minimise, free variables - can be anything, solution - material which meets objectives.
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What are material bar and property charts used for?
Materials bar charts and property charts are used to make selections.
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What is a component and what is shape factor?
Component/structure - material made into a shape. Shape factor - measures efficiency of material usage.
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What's the bending stiffness shape factor formula?
Bending stiffness S is proportional to EI. Bending stiffness factor = EI/EI0 and I0=A^2/12 so S/S0=12I/A^2
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What is bending strength shape factor?
σ= My/I=M/Z Z is section modulus Z0= b0^3/6. Bending strength factor = Z/Z0= 6Z/A^3/2
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What are products of material life cycle?
In material lifecycle, material production, manufacture, product use and disposal all demand energy, chemicals, and materials, and emissions released in process. These are phases/
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What are some eco impacts?
Eco-impact leads to resource depletion, energy consumption, toxic residues, and CO2, NOX, SOX emission
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What features does the materials tree have?
Materials tree has kingdom (materials), family (ceramics, glasses etc), class (steels etc), member(1000+), and attributes.
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Why concrete?
Widely available constituents, low technology, strong and stiff in compression and low price.
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How can concrete be reinforced?
Plain concrete for paving has no reinforcement, reinforced concrete uses reinforcing bars. Pre-stressed concrete has tensioned reinforced bars. Pre-tensioned - tensioned before casting, post-tensioned - tensioned after.
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