Properties/Materials Flashcards

Pregunta	Respuesta
Explain the working properties of materials?	Strength is the ability to withstand forces without breaking. Hardness is the ability to withstand scratching, abrasion or denting. Toughness is the ability to withstand breaking or snapping. Malleability is the ability to be bent and shaped without breaking. Elasticity is the ability to return to its original shape after being stretched. Ductility is the ability to be drawn into a wire.
Explain the physical properties of materials?	Electrical Conductivity is the ability to let electricity travel through them. Thermal Conductor is the ability to let heat travel through them. (Insulators don't!) Fusibility is the ability to melt fast and have low melting points. Density is the measure of its mass per unit volume. Absorbency is the ability of soaking up moisture.
Explain the properties of Non-Metals and Metals?	Non-metals: - more brittle (opposite of toughness) - poor electrical conductors - low density Metals: - strong - malleable - good conductors - poor fusibility
Explain an Alloy?	An Alloy is a mixture of two or more metals, or a metal mixed with one or more elements. The alloy has different properties to the individual materials its made from.
Give examples of ferrous metals, non-ferrous metals and alloys?	Ferrous Metals: Cast Iron, Low Carbon Steel, High Carbon Steel Non-Ferrous Metals: Aluminium, Copper, Tin, Zinc Alloys: High Speed Steel, Stainless Steel, Brass
Explain Thermoforming Plastic and Thermosetting Plastic?	A Thermoforming plastic don't resist heat well so they can be shaped through heating, melting and remoulding. A Thermosetting plastic resist heat so they can't be reshaped. They undergo a chemical change when heated/melted to make a product that becomes permanently hard and rigid. Thermoforming can be recycled, ground down, melted and re-used, while Thermosetting can't be recycled or re-used since they can't be heated/melted and reshaped again.
Give examples of Thermoforming Plastics and Thermosetting Plastics?	Thermoforming Plastics: Acrylic, High-density polyethylene (HDPE), Polyethylene terephthalate (PET), High impact polystyrene (HIPS), Polyvinyl chloride (PVC), Polypropylene (PP) Thermosetting Plastics: Epoxy Resin (ER), Urea-Formaldehyde (UF), Melamine-Formaldehyde (MF), Phenol-Formaldehyde (PF), Polyester Resin (PR)
Explain the types of Paper?	Cartridge paper is high quality and has a textured surface. Layout paper is thin and translucent (see light through it). Tracing paper is semi-transparent. Grid paper can have a square or isometric pattern on it. Bleed-proof paper stops ink from spreading out.
Explain the types of Board/Card? (1/2)	Solid white board is a high quality bleached surface, ideal for printing. Ink jet card doesn't allow the ink to bleed. Corrugated card is made of a fluted inner core sandwiched between tow outer layers, that can be printed on and the flutes add strength and rigidity.
Explain the types of Board/Card? (2/2)	Duplex board has different textures and colours on each side. Foam core board is stiff, lightweight and consists of polystyrene foam between two thin layers of card. Foil-lined board is a board with an aluminium foil lining, to keep flavours in and air and moisture out.
Explain the difference between Softwoods and Hardwoods?	Softwoods grow in colder climates and are fast growing. They are also cheap and readily accessible. They also have leaves like needles, usually evergreen and have cones. Hardwoods grow in warmer climates and are slow growing. They are more expensive, have broad flat leaves and a tighter grain. They are usually deciduous so they lose their leaves in autumn. They are also denser and harder than softwoods.
Give examples of Softwoods with their properties?	Pine - strong, cheap, knotty and yellow with brown streaks. Larch - hard, tough, durable, resistant to rot and attractive yellow/reddish brown colour. Spruce - hard, good strength-to-weight ratio, knotty, not very durable and a reddish brown colour.
Give examples of Hardwoods with their properties?	Oak - tough, durable, strong, attractive grain, finishes well, corrodes steel and light brown colour. Mahogany - durable, easy to work with, expensive and red-brown colour. Beech - hard, bent using steam and pinkish-brown colour. Balsa - very low density, very soft, easy to cut and shape, high strength-to-weight ratio and white or tan colour. Ash - tough, absorbs shock well, attractive and pale cream colour.
Explain the types of Fibres?	Natural Fibres can be harvested from plants and animals. These are renewable resources, that are biodegradable and recyclable. They are also absorbent and strong when dry, but have poor resistance to biological damage. Synthetic Fibres are made from polymers. They are less sustainable than Natural Fibres. They are resistant to biological damage, can be changed by heating to form different shapes and textures, but aren't very absorbent.
Give examples of Natural Fibres and their properties?	Cotton - smooth - strong, hard wearing, absorbent, comfortable, non-static, un-allergic, cool in hot weather BUT creases easily, highly flammable, poor elasticity and dries slowly - denim, corduroy and calico. Wool - soft/coarse - warm, absorbent, good elasticity, low flammability, crease-resistant BUT dries slowly, feels itchy and fairly expensive - knitted fabrics, Harris Tweed, gabardine, jersey and felt. Silk - smooth/glossy - resistant to shrinking/stretching, absorbent, low flammability, lightweight and sun-resistant BUT creases easily, weak when wet and expensive - organza, chiffon and satin.
Give examples of Synthetic Fibres and their properties?	Elastane - soft - high elasticity, strong, hard wearing, lightweight and sun/biological resistant BUT not absorbent, high flammability and not biodegradable - LYCRA Polyester - smooth - strong, hard wearing, low flammability, good elasticity, cheap, resists creasing, dries quickly and resists biological damage BUT not absorbent, not biodegradable and melts as it burns - DACRON Polyamide - many different finishes - strong, hard wearing, warm , high elasticity, crease resistant, biological damage resistant and fairly cheap BUT not very absorbent, damaged by sunlight and melts as it burns - nylon
Explain Yarns and Fabrics?	Yarns are threads that are woven or knitted to make fabrics. Filaments can be spun or used as they are and staple fibres are spun to produce yarns. Yarns made from filaments are smooth, while yarns made from staple fibres tend to be hairier. Fabrics are made from fibres and yarns. Woven Fabrics are made from interlacing tow sets of yarns. Knitted Fabrics are made by interlocking one or more yarns together using loops. The loops trap air, so they insulate and stretch more woven fabrics. Non-Woven Fabrics are layers of fibres held together by bonding or felting. They don't stretch and aren't very strong.
Explain Manufactured Boards, how they are manufactured and their properties?	Manufactured boards are processed pieces of wood combined with glue and compressed into panels. Medium Density Fibreboard (MDF) is made from tiny fibres of softwood timber held together by glue, has no natural grain, cheap, dense, smooth and damaged by moisture. Plywood is made up of several layers of softwood or hardwood, glued together with their grain at right angles to one another, making it very strong. Chipboard is made by compressing wood chips, shavings and sawdust together with glue with a veneered surface. Its cheap but not very strong and absorbent so easily damaged by moisture.
Explain Modern Materials and give examples?	Modern materials are materials that have been developed with a specific application in mind. They can be developed by inventing new or improved manufacturing processes. Graphene, Metal Foams, Titanium, Liquid Crystal Displays (LCDs), Coated Metals and Nanomaterials.
Explain the types of Smart Materials and give examples? (1/2)	Samrt Materials change their properties in response to stimuli. The changes are often reversible when the stimulus is removed. Shape Memory Alloys are alloys that remember their original shape. They are easily shaped, but return to their original shape when heated above a certain temperature. An example of this would be Nitinol which can be used in glasses, and if bent can be returned to their original shape by putting them in hot water.
Explain the types of Smart Materials and give examples? (2/2)	Photochromic Pigments change colour reversibly in response to light. An example would be spectacle lenses with these pigments that turn into sunglasses when sunny, or a t-shirt design that only appears in sunlight. Thermochromic Pigments are used in colour-changing and react to temperature. The colour changes as the temperature changes. They are used in baby feeding spoons so the parent knows if the food is too hot or not.
Explain Composite Materials and give examples.	Composites are made from two or more different materials bonded together. Glass reinforced plastic (GRP) is made from glass fibres that are coated in a thermosetting plastic resin and is stronger, tougher, heat-resistant and easy to mould into complex shapes. Carbonfibre reinforced plastic (CRP) is made from carbon fibres that are coated in a thermosetting plastic resin and is lighter, tougher, stronger than GRP but more expensive.
Explain Technical Textiles and give examples? (1/2)	Technical Textiles are enhanced fabrics, designed purely to be functional and not aesthetically pleasing. Kevlar - A synthetic fibre that can be woven into a really strong fabric that's resistant to abrasion. It is used for bulletproof vests, motorcyclist clothing and reinforcing tyres. Nomex - This enhanced fabric has fire-resistance built into the fibres, so it can't be washed or worn away. It is used for firefighters and racers overalls.
Give examples of Technical Textiles? (2/2)	Micro encapsulation - This is where tiny droplets of a chemical are coated in shells called microcapsules and embedded in a microfibre fabric, woven from very thin synthetic fibres. These chemicals tend to have a function e.g. insect repellent, odour neutralisation, perfume. They are used in antibacterial socks and scented lingerie. Conductive Fabrics - These use fibres that can conduct electricity. They are used to integrate electronics into clothing and in touchscreen gloves.

Siguiente

Descripción

Resumen del Recurso

Similar

	Creado por Riley Loades hace más de 5 años