Metals

Metals Making elemental metals; = metallurgy Solidification: The origin and control of grains & phases

Thermal Mechanical Processing: Control of microstructure.

Wrought products Products that have been formed (e.g. rolling, extrusion, drawing, forging) -

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Properties Elastic deformation; Plastic deformation; Yield strength; Modulus of elasticity;

Barriers to slip; -

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L o A o R Reducing grain size o o . Second phase o . o .

A two-phase region exists for …………………………………, bounded by the so …………………………..’ and ‘solidus’ – can be observed during both solidification and melting

Ceramics Sources of defects in ceramics -

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Ceramic fabrication methods – particulate Slip casting -

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Sintering -

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Additives and sintering aids -

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Design with Ceramics Flexural 3 point bend test Designing with a strength distribution; -

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The design stress limit has to be lowered to allow for -

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Stress intensity at tip of crack -

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Polymers A compound of high …………………………. (normally organic, mostly hydrocarbons) with structure composed of chains of …………………………. Saturated; . Unsaturated; . Steps in Polymerisation -

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Thermoplastics; b… Polymer processing -

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Polymer additives Improve mechanical properties, process ability, durability, ect Fillers; -

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Plasticizers; -

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Stabilisers; -

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Lubricants; -

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Colourants; -

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Flame retardants; -

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Molecular weight distribution M= ̅̅̅̅ 𝑀 𝑛 = ̅= 𝑀 Degree of polymerisation =

Polymer crystallinity -

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. . Crystalline regions; o . o . Polymers are rarely 100 % crystalline o . o . Semi-crystalline polymers o . o . o . Causes changes to o . o . Craze; formation prior to cracking. o . o .

Thermosets; Irreversible plastics -

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Graphene -

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Extraordinary properties of graphene -

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How Graphene is used -

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Unique electrical properties Electrons travel through the graphene sheet as if they have no mass, as fast as just 100th of the speed of light, more than 100 times faster than those in silicone

Graphene based nano-composites When ……………………………, graphene can ……………………………………., while making them more heat resistant and …………………..robust. This ………………………………………………………………….. strong materials, ……………………………, elastic and lightweight. Strategies making graphene Top down -

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Challenges of large scale production -

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Bottom up -

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Aluminium alloys Automotive aluminium replacing sheet steel -

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Solution treatment: to dissolve Mg and Si from previous slow cooling steps e.g. casting -

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Fast quenching; -

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Ageing; (heating) -

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Additive manufacturing Polymer 3D printing -

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Metal 3D printing Direct metal deposition -

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Laser powder bed -

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Metal Powders -

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Heat transfer, distortion; -

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Photovoltaics -

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Advantages -

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Challenges -

Requirements -

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Semiconductors -

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Optimisations Antireflective coatings; -

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Textured surfaces; -

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Optimisation of contacts; Charge separation -

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