UNIT 3: Technical materials




KEY WORDS: raw materials, manufactured goods, to tear(romper con las manos), to smooth(lijar), drawer(cajón), card(cartulina), cardboard(cartón),alloy,


 BOOK UNIT Nº10 (link here to see it): "FORCES"
* The aim of the test is..
* Properties: "These steel cables can resist tension. They are able to resist tension".
* Passive form: "This plastic can be stretched, but it cannot be compresed".
* Verbs that contain the idea of cause as part of their meaning: Harden, lighten, widen, etc.
* Colour: reddish, bluish, greenish, etc. 
INDEX:

* INTRODUCTION: VIDEO
1.- TECHNICAL MATERIALS.
2.- ALLOYS.
3.- PROPERTIES
4.- MANUFACTURED PROCEDURES.
0.- INTRODUCTION: Whatch this youtube (FiberGlass from Airbus of National Geographic.) and answare the folloween questions:
http://www.youtube.com/watch?feature=player_embedded&v=E8vCqkyEUDs

 1.    Write True or False

  • a.    The first material in the Airbus 380 is light weight steel F
  • b.    Glass becomes a liquid at about 270 º Farenheit F
  • c.    Fiber glass is stronger and more flexible than ordinary glass T
  • d.    Fiber glass can be woven like textiles to produce sheets of material T
  • e.    The window doesn´t break because the individual fibers don´t break F
  • f.    The aluminum provide strength to the composite F
2.    Fill in the gaps

  • a.    The outer skin of the Airbus 380 must be superlight and strength
  • b.    Fiber glass is about six to ten times the liquid of steel
  • c.     ……………….. resin is added afterwards
  • d.    When it dries it sticks the fibers together to create glass in its tougher form.
  • e.    Fiber glass is even aluminium when combined in a composite with fiberglass.
  • f.    Aluminium provides the strength that …………………… lacks
3.    Answer this question: In the video the terms “Glass fiber” and “Fiber glass” are mentioned:
Are they the same thing? What does each term mean?
No, they aren't glassfiber is an HILO and fiberglass is a material






1.- TECHNICAL MATERIALS.

 1.- RAW MATERIALS are substances that are extracted directly from natural object. The can be classified into three main categories: animal origin (wool, silk, hides,..) vegetal origin (cotton, hard wood and soft wood ("timbers"), cork, ..) mineral origin (marble, clay, iron...)

 2.- MATERIALS  are the raw materials transformed by physical or chemical processes: paper, planks of wood, plastic, metal, glass, etc.

  Manufactured BOARDS of wood: are pieces or stripes of wood glue together:
PLYWOOD(contrachapado) ,CHIPBOARD(aglomerado), MDF, BLOCKBOARD, HARDBOARD(conglomerado).

3.- MANUFACTURED GOODS are any objects created by humans to satisfy their needs and improve their standard of living. The manufactured good can be made of various pieces made from various different materials:  furniture, cars, etc.

 4.- TECNICHAL MATERIALS: Common materials used to make manufactured goods:

  • WOOD:  furniture, floors, tool hadles, decorative objects, etc.  


  1. Softwood timbers usually come from coniferous trees - that is, evergreen, needle-leaved, cone-bearing trees such as fir and pine. 
  2. Hardwood timbers come from broad-leaved, deciduous trees, and are more important in Design and Technology than softwood timbers.

  • METALS: tools and machines, electrical components, fixtures and fasteners, etc.

  1. A) FERROUS. There are metals contain iron. All ferrous metals are MAGNETIC. Examples are cast iron, mild steel, medium carbon steel, high carbon steel, stainless steel, and high speed steel.
  2. B) NON-FERROUS. There area metals do not contain iron. They are not magnetic and are usually more resistant to corrosion than ferrous metals: aluminium, duralumin, copper, zinc, brass, gilding metal and tin

  • PLASTICS: PP, PU, PVC, PE, ..eg.: toys, containers, tubing, etc.
  • CONSTRUCTION  MATERIALS:  bricks, roofing tiles, walls, etc. 
 
2.- ALLOYS.
An alloy is a mixture of two or more metals. 
When a material is needed which requires certain properties and this does not exist in a pure metal we combine metals.
Pure white aluminium is very soft and ductile. Other elements can be added to create an aluminium alloy. This can produce a metal which is stronger than Mild Steel has improved hardness and is resistant to corrosion while still remaining light in weight.

  • STEEL= IRON + CARBON.
  • POOR STEEL= IRON + MUCH CARBON (eg: manhole cover)
  • BRASS= COPPER + ZINC.
  • BRONZE= COPPER + TIN.
  • PEWTER=  TIN + ANTIMONY + COPPER.
 



3.-PROPERTIES OF MATERIALS.
 

Hardness
is the ability of a material to resist wear, scratching and indentation. The resistance a materials has to cutting and surface indentations.
Toughness
The opposite of Brithleness. Toughness is the ability of a material to withstand blows or sudden shocks without breaking.This describes the amount of energy a material can absorb without breaking. We measure a material's ability to absorb shock.
Tensile Strength
The maximum force a material can withstand
((in tension(pulling) compression(squashing) , torque(twisting) and shearing(sideways pressure)))
Malleability
The amount of hammering, pressing and shaping a material can take without breaking.
Ductility
Ductility is the ability of a material to deform, usually by stretching along its length.The length that a material can be stretched without breaking. 
Elasticity
It´s the ability of a material to be bended and then return to its original shape and size when released.
Conductivity
Is the ability to conduct heat or electricity.
Heaviness
The denseness of materials. A dense material will be heavy in relation to its size. Density=Mass/Volume
Strength
The measure of how a material withstands a heavy load without breaking.




Fusibility
Fusibility is the ability of a material to change into a liquid or molten state when heated to its melting point
others: Hardness, Opaque/Translucent/Transparent;  Welding,  Plastilicty, Waterproof/Permeability, Fragily, Britleness ,  Fold/Bend





4.- MANUFACTURED PROCEDURES.
Tools: The tools and machines increase our ability to do work with materials. To mark(punch, compass, square, pencil, rule, scriber, templates), to cut-drill(saw, jack plane, jig-saw, drilling machine, chisels), to bend (vice, hammer), to smooth off (files). 

  • MARKING OUT:'Marking out' means the transfer of shapes and lines onto the material, as guides for cutting, bending or shaping them. Accurate marking out is essential if the different parts of the product are to fit together properly. You can use this tools: pencil, scriber, compasses, templates, etc.
  • SHAPING BY WASTING TOOLS: Shaping by wasting simply means cutting away material to leave the desired shape.The tools that you can use are: circular saw bench, jig saw, Drilling machine, Hand router or Computer Numerical Control (CNC) milling machin, etc.
  • BENDING: Metals can be bent in a vice or in folding bars. Thin metal may be bent whilst cold, while thicker metal may need heating or annealing. Larger pieces of metal may also need to be heated first. 
  • SHAPING BY REFORMING: Reforming is a method of shaping materials which changes their overall appearance by first melting or softening them into a paste, then hardening them. Reforming methods include casting, extrusion and injection moulding.
  • EXTRUSION: Extrusion is used to produce long, but fairly thin products such as pipes or curtain tracks. Both plastics and metal can be extruded. The material is forced through a die, which contains a hole which is the same shape as the required product.
  • INJECTION. Injection moulding is a similar process to die casting. A metal mould is used and softened or molten plastic is forced into the mould by pressure from a screw thread or pneumatic plunger. The mould is made in two parts to allow the moulding to be removed. Polythene, polystyrene, polypropylene and nylon are the plastics most often used in injection moulding, which is used extensively in industry. 

ACTIVITIES Nº1.
1.- Which raw material do these materials come from?

a) glass  b) steel   c) plastic  d) porcelain e) planks  f) concrete
2. What manufactured goods can we made from the materials of the exercise before.
3. Complete the sensences:

  • " ____________ materials can be stretched. They return to their _____ shape and size alfter stretching"
  • "_________ materials can also be stretched, but they remain permanently ______ after stretching". 
4.- Write a list of FIVE manufactured goods made with elastic materials.
5. Order from greater to lesser hardness the following materials:

plasticine, plaster, ceramics, diamond, talc.
6. Name three objects made with permeable materials and another three made with waterproof materials.
7. Classify the following textile materials into natural or syntetic:

polyester, cotton, polyamide, wool, jute, naylon, silk, linen, viscose, lycra. rayon.
8. What are the most important properties of these materials:

a) ceramic b) concrete c) fiberglass d) graphithe e) steel.

9.- What are these made of: 

a)aluminium b)ceramic c)fiberglass d)grafithe e)titanium f)nylon g)policarbonate h)rubber i)steel j)polyestyrene
10.- Find out a material with the properties of:
a)soft+light b)ductil+good conductor c)hard+tough+non rust+alloy
11.-  Give an example of a suitable material tha may be used to make:
  • a) garden tools:
  • b) most work-shop tools
  • c) tough kitchen sink units
  • d) wire electrical cables
  • e) to protect doctors and dentists from harmful radiation when using X-rays
  • f) Panels of Land-Rovers.
  • g) Ornaments.
  • h) jewllery. 
  • i) car gears.
ACTIVITIES Nº2
1. Look for an image of each sort of  manufactured process and paste it into your blog.
ACTIVITIES Nº3.
1. Complete the table into your blog:


 Name  and  melting  point
 Composition
 Properties and  characteristics
 Principal uses
 Aluminium
 660°C
 Pure  aluminium 
 (an element)
 Hard, tough,  malleable  and  ductil
 Kitchen equipment, window  frames, general cast  components
 Duralumin
 650°C
 Aluminium  with 4%  copper, 1%  manganese  and  some  magnesium
 Lightweight,  malleable,ductile  and impermeable
 Fasteners, automotive
 Copper
 1080°C
 Pure copper      (an element)
 Good electrical  and thermal  conductor and  very ductil
 Electric wires, heat  exchanges in boilers and  pipes
 Zinc
 420°C
 Pure zinc 
 (an element)
 Weak metal,  extremely  resistant to  corrosion, low  melting point
 Aerospace and automotive  industries, brass  manufacturing and  metallurgy
 Brass
 900-  1000°C
 Alloy of  coopper  and  zinc
 Resistant to  corrosion, fairly  hard, good  conductor of heat and  electricity
 Electric industry,  ornamentation, musical  instruments
 Bronze
 1020°C
 Alloy of 88%  copper and  12% tin Very resistnat to  corrosion, good  heat  and  electricity  conductors, heavy  and  strong. Statues, ornamentations,
 junctions,  musical
 instruments
 Steel
 1535°C
 Mixture betwen  iron and carbon
 Tough, strong,  malleable, hard and good  conductor
 Construction structures, indsutrial  plants, large structures(bridges,  towers, buildings), automotive, join  elements and appliances

 


ACTIVITIES Nº4.

1. Make a timeline about a TOOL over the history. 
ACTIVITIES Nº5.

 1. Complete the table of the Density of  these materials:

  1. ALUMINIUM:   mass=200g; volume=74cm3; density: 2.7 g/cm3
  2. COPPER: mass=475g; volume=53.37 cm3; density= 8.9 g/cm3
  3. ZINC: mass=347.9g; volume=49cm3; density= 7.1 g/cm3
  4. LEAD: mass= 475g; volume=42cm3; density=  11.3g/cm3
  5. WOOD: mass= 15g ; volumen=20cm3 ;density= 0.75 g/cm3
  6. MARBLE: mass=125g ;  volumen=48.07cm3  ;density= 2.6 g/cm3

 ACTIVITIES Nº6:  

 Explain what is meant by the term alloy?
An alloy is a mixture of two or more metals which is produced when a material that requires certain properties and it doesn't exist is needed.

Explain in detail the difference between ferrous and non-ferrous metals.
Ferrous: they own a characteristic bright, are good heat and electricity conductors, are malleable and ductils, almost all of them are solid and have high melting point.
Non ferrous: they don't have any bright, can be solids, liquids or gases, are bad heat and electricity conductors, are very fragiles and they have loww melting and boiling points. 

Define the terms ductile, malleable and corrosion resistant.
Ductile: it's when a metal deforms, usually by stretching along its length.The length that a material can be stretched without breaking. 
Malleable: when a metal is malleable it indicates the amount of hammering, pressing and shaping a material can take without breaking.
Corrosion resistant: when a metal is protected or avoid corrosion

Suggest a use for: Mild Steel, stainless steel, Aluminium, Copper, Brass & Lead
    Mild steel: wires of fences
    Stainless steel: appliances
    Aliminium; foil (for packing)
    Copper:pipes
    Brass: musical instruments
    Lead: protection against x-rays


 ACTIVITIES Nº7.

1.- Make a mind-map on a card about A TECHNICAL MATERIALS and its: properties, uses, object, types, tools, etc. 


ACTIVITIES Nº8.

1.- Find out and draw three types of MATERIALS JOINTS.  


 ACTIVITIES Nº9.

1.- Make a presentation of the comparition of two types of metals.


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