IB Design Technology - Topic 4 (Final Production)

Strain

The response of a material due to stress, defined as the change in length divided by the original length

Stress

A force on a material divided by the cross sectional area of the material

Stiffness

Resistance to deformation by an applied force

Super alloy

Exhibits exceptional mechanical properties, resistance to thermal creep deformation, good surface stability, and resistance to corrosion

Synthetic fibers

Fibers made from man made materials, spun into threats; the joining of monomers into polymers through polymerization

Tempering

Heat treating process that increases the toughness of iron based metals by heating the metal and allowing it to cool in air. This can increase ductility and decrease brittleness

Knots

Imperfections in timber, caused by the growth of branches in the tree that reduces its strength

Lacemaking

A method for creating a decorative fabric that is woven into symmetrical patterns and figures

Laminated boards

Sheets of material made from layers of veneers (plywood)

Laminated object manufacture (LOM)

A rapid prototyping system that creates a 3D product by converting it into slices, cutting the slices, and joining the slices

Lamination

Covering the surface of a material with a thin sheet of another material typically for protection, preservation, or aesthetic reasons

Load Capacity (Robots)

The weight a robot can manipulate

Machine to machine (M2M)

Wired or wireless communication between similar devices

Magneto-rheostatic

The smart property relates to a fluid that can undergo a dramatic change in viscosity when exposed to a magnetic field

Man-made timber

Also known as engineered wood or composite wood, these are wood products that are made by binding or fixing strands, particles of fibers, veneers of boards of wood together with adhesives or other fixing methods to create composite materials. Typical examples include MDF, plywood and chipboard

Twisting

A distortion in which the 2 ends of a materiel do not lie in the same plane

Mass

Relates to the amount of matter in a given volume

Mass customization

A sophisticated CIM system that manufactures products to individual customer orders. The benefits of economy of scale are gained whether the order is for a single item or for thousands

Mass production

The production of large amounts of standardized products on production lines, permitting a very high rate of production per worker

Material selection chart

A chart used to identify appropriate materials based on the desired properties

Mechanical properties

Properties of a material that involve the relationship between stress and strain or a reaction to an applied force

Mechanized production

A volume production involving machines controlled by humans

Multi task robots

A type of robot that can preform more than one task in a manufacturing environment

Automated production

A volume production process involving machines controlled by computers.

Bio-compatibility

The product ensures the continued health of a biological environment.

Brittle

Breaks into numerous sharp shards

Design for disassembly

Designing a product so that when it becomes obsolete it can easily and economically be taken apart, the components reused or repaired, and the materials recycled.

Design for Materials

Designing in relation to materials during processing

Design for process

Designing to enable the product to be manufactured using a specific manufacturing process, for example, injection molding.

Dry rot

When timber is subject to decay and attacked by fungus

Ductility

The ability of a material to be drawn or extruded into a wire or other extended shape

Elasticity

The extent to which a material will return to its original shape after being deformed

Electrical insulator

Reduces transmission of electric charge

Electrical resistivity

The measure of a material's ability to conduct electricity. A material with low resistivity will conduct electricity well.

Electro-Rheostatic

This smart property relates to a fluid that can undergo a dramatic change in its viscosity when exposed to an electric field.

Equilibrium Moisture Content (EMC)

EMC is at which the moisture content of wood achieves an equilibrium with the environment which can be affected by humidity and temperature.

Felting

A method for converting yarn into fabric by matting the fibers together

First Generation Robots

A simple mechanical arm that has ability to make precise motions at high speed. They need constant supervision by a human operator.

Free moisture

The moisture within timber that is contained within the cell cavities and inter cellular spaces.

Glass

A hard, brittle and typically transparent amorphous solid made by rapidly cooling a fusion of sand, soda, and lime.

Grain Size (metals)

Metals are crystalline structures comprised of individual grains. The grain size can vary and be determined by heat treatment, particularly how quickly a metal is cooled. Quick cooling results in small grains, slow cooling results in large against. Grain size in metals can affect the density, tensile strength and flexibility.

Design for Manufacture

Designers design specifically for optimum use of existing manufacturing capability

Craft production

A small-scale production process centered on manual skills.

Design for assembly

Designing taking account of assembly at various level, for example, component to component, components into sub-assemblies and sub-assemblies into complete products.

Creosote

A material that penetrates the timber fibers protecting the integrity of the wood from attack from borer, wood lice, and fugal attack.

Density

The mass per unit volume of a material. Its importance is in portability in terms of a product's weight and size. Design contexts include, pre-packaged food (instant noodles) is sold by weight and volume, packaging foams.

cupping

The edges of a piece of wood are higher or lower than the center due to warping

Continuous flow

A production method used to manufacture, produce or process materials without interruption.

Creep

The slow, permanent deformation of a solid material under the influence of a mechanical stress.

Computer numerical control (CNC)

Refers specifically to the computer control of machines for the purpose of manufacturing complex parts in metals and other materials. Machines are controlled by a program commonly called a "G code". Each code is assigned to a particular operation or process. The codes control X, Y, Z movements and feed speeds.

Compressive strength

The ability of a material to withstand being pushed or squashed

Composite

a material comprised of two or more constituent materials that have different properties

Chemically inert

Lack of reactivity with other materials

Bowing

A warp along the length of the face of the wood

Batch production

Limited volume production (a set number of items to be produced)

Tensile strength

Ability of a materials to withstand pulling force

Assembly line production

A volume production process where products and components are moved continuously along a conveyor. As the product goes from one work station to another, components are added until the final product is assembled.

Thermal expansion

The measure of the degree of increase in dimensions when an object is heated. This can be measured by an increase in length, area, or volume. Can be found in fractional increase per kelvin

Work envelope

A fixed 3D space where work activities take place, considering clearance and reach.

Work hardening

Also known as strain hardening or cold working, this is the process of toughening a metal through plastic deformation.

Subtracting/Wasting techniques

Manufacturing technique that cuts away material to create a component

Yarn

A long continuous length of interlocked synthetic or natural fibres

Thermo-electricity

Smart material that when heated can produce an electric current. Comprised of 2 dissimilar conductors

Wood treatment

Treatment of wood can involve using solutions, which make the wood poisonous to insects, fungus, and marine borers as well as protecting it from the weather.

Volume

The quantity of a 3 dimensional object enclosed by a boundary. The space that an object takes up

Warping

A distortion in wood caused by uneven drying, resulting in material bending or twisting

Third gen. robots

Autonomous robots that can operate without supervision from people. Own central control unit. Swarms of small units fit in this catagory

Transparency

Ability to allow light to pass through it with minimal distortion

Toughness

Ability to resist the prorogation of cracks

Thermosetting plastic

A plastic that when it takes its shape will permanently stay in that shape

Wood recycling

This method is the process of turning waste timber into usable products. Recycling timber is a practice that was popularized in the early 1990s as issues such as deforestation and climate change prompted both timber suppliers and consumers to turn to a more sustainable timber source.

Thermoplastic

A plastic that when heated can be reshaped and reformed

Thermal condutivity

Measurement of how fast heat will transfer through material with a given temperature

Weight

Relies on mass and gravitational forces to provide measurable value. Weight is technically measure as a force, which is the Newton, i.e. a mass of 1 Kg is equivalent to 9.8 Newton [on earth].

Additive Techniques

Manufacturing techniques that add material in order to create it

Alloy

A mixture that contains at least two metals. This can be a mixture of metals or a mixture of metals and non-metals.

Kiln seasoning

Thermally insulated chamber, an oven, which produces temperatures sufficient to complete some process, such as hardening, drying, or chemical changes

Knitting

A method for converting yarn into fabric by creating consecutive rows of interlocking loops of yarn

Piezoelectricity

A property of a smart material. A piezoelectric material gives off a small electrical discharge when deformed.

Weaving

The act of forming a sheet like material by interlacing long threads passing in one direction with other at a right angle to them.

Aesthetic characteristics

Aspects of a product that relate to tastes, texture, smell and appearance

Air-drying

Process of stacking sawed timber in the open or in large shed. There is little control over the drying process and the wood will warp

Physical properties

Any property that is measurable that describes a state of materials, for example, mass, weight, volume and density. These properties tend to be the characteristic of materials that can be identified through non-destructive testing (although some deformation is required to test hardness).

Plasticity

The ability of a material to be changed in shape permanently

Reforestation

The process of restoring tree cover to areas where woodlands or forest once existed. If this area never returns to its original state of vegetative cover the destructive process is called deforestation

Seasoning

The commercial drying of timber which reduces the moisture content of wood.

Second generation robots

Robots that are equipped with sensors that can provide information about their surroundings. They can synchronize with each other and do not require constant supervision by a human; however, they are controlled by an external control unit.

Shape memory alloys

Metals that when deformed, can spring back into its original shape once released.

Shaping techniques

Manufacturing methods for modifying the shape of a material.

Single task robots

Robots that can perform one task only.

Smart materials

Materials that have been designed to have one or more properties that can be modified when subject to an external stimuli in a way that the output can be controlled.

Softwood

The wood from a coniferous (evergreen) tree.

Natural Fibres

Materials produced by plants or animals that can be spun into a thread, rope or filament

Non-toxic

Absence of toxic breakdown products/lack of reactivity.

One-off production

An individual (often craft-produced) article or a prototype for larger scale production.

Oxidation resistance

A property of a metal that means that it does not readily react with oxygen and degrade.

Paper-based rapid prototyping

Often the first step in a rapid prototyping process, this type of prototyping is widely used in UCD for designing and testing interfaces.

Photochromicity

A property of a smart material. This material changes colour in response to an increase in light. When the light source is removed, it returns to its original colour.

Particle boards

A material made from different sizes of wood chips and joined with glue.