Andrea Arenas Villalta: Unit 3.- Materials

UNIT3. TECHNICAL MATERIALS.

There´s an old saying: "MEASURE TWICE, CUT ONCE"

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: "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:

1.- TECHNICAL MATERIALS.

2.- ALLOYS.

3.- PROPERTIES

4.- MANUFACTURED PROCEDURES.

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.

Softwood timbers usually come from coniferous trees - that is, evergreen, needle-leaved, cone-bearing trees such as fir and pine.
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.

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.
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.
Heat and Electrical Conductivity	The measure of how well a material can 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.
Conductivity	Is the ability to conduct heat or electricity.
Elasticity	Is the ability to bed and then to return to its original shape and size.
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-> sand

b) steel-> carbon and iron

c) plastic->oil

d) porcelain-> ceramic

e) planks->wood

f) concrete-> sand and concrete.

2. What manufactured goods can we made from the materials of the exercise before.

a) glass: window

b) steel: a structure of a building

c) plastic:pen

d) porcelain: doll

e) planks: trunk

f) concrete: cement
3. Complete the sensences:

" _Elastic_ materials can be stretched. They return to their _original_ shape and size alfter stretching"
"_No elastic_ materials can also be stretched, but they remain permanently _former shape_ after stretching".

4.- Write a list of FIVE manufactured goods made with elastic materials.
- Gum.

- rubber.

- elastic bed.

- Scrunchie.

- String of a slingshot

5. Order from greater to lesser hardness the following materials:

diamond, plaster, ceramic,plasticine, talk.

6. Name three objects made with permeable materials and another three made with waterproof materials.

Sponge, Clothes, napkin,
Umbrella, oilskin, boots.

7. Classify the following textile materials into natural or syntetic:

polyester--> Syntetic
cotton-->natural
polyamide-->syntetic
wool-->natural
jute-->syntetic
naylon-->syntetic
silk-->natural
linen-->natural
viscose-->syntetic
lycra-->syntetic
rayon-->syntetic

8. What are the most important properties of these materials:

a) ceramic: hardness, heat conductivity, heaviness

b) concrete : hardness, toughness, heaviness, strength,

c) fiberglass: ductility, elasticity (hot), heaviness, hardness, fusibility

d) graphithe: hardness, fusibility, malleability (hot)

e) steel: hardness, heaviness, strength, ductility, malleability, electric conductivity.

9.- What are these made of:

a)aluminium: argon

b)ceramic: Clay

c)fiberglass: glass

d)grafithe: grafeno

e)titanium: mineral

f)nylon: plastic

g)policarbonate: Co2 + epoxidos

h)rubber: gum

i)steel: iron and carbon

j)polyestyrene:polimerización del estireno.

10.- Find out a material with the properties of:

a)soft+light: textiles

b)ductil+good conductor: copper

c)hard+tough+non rust+alloy: steel

11.- Give an example of a suitable material that may be used to make:

a) garden tools-->steel and wood
b) most work-shop tools-->steel
c) tough kitchen sink units--> steel
d) wire electrical cables-->copper
e) to protect doctors and dentists from harmful radiation when using X-rays-->lead
f) Panels of Land-Rovers.-->wood and stone
g) Ornaments.--> wood and ceramic
h) jewllery. -->diamond
i) car gears.-->steel

ACTIVITIES Nº2

1. Look for an image of each sort of manufactured process.

ACTIVITIES Nº3.

1. Complete the table:

Name and melting point	Composition	Properties and characteristics	Principal uses
Aluminium ***°C	Pure aluminium (an element)		Kitchen equipment, window frames, general cast components
Duralumin 650°C	Aluminium with 4% copper, 1% manganese and some magnesium
Copper 1080°C	Pure copper (an element)
Zinc ***°C	Pure zinc (an element)	Weak metal, extremely resistant to corrosion, low melting point
Brass 900-1000°C	Copper + Zinc	Resistant to corrosion, fairly hard, good conductor of heat and electricity
Bronze ****°C	Copper + Tin
Steel ****°C

ACTIVITIES Nº4.

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

Ax over history
PREHISTORY	MIDDLE AGES	NOW

ACTIVITIES Nº5.

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

ALUMINIUM: mass=200g; volume=74cm3; density:2,7g/cm3
COPPER: mass=475g; volume= 53,3cm3; density= 8.9 g/cm3
ZINC: mass= 347,9g; volume=49cm3; density= 7.1 g/cm3
LEAD: mass= 475g; volume=42cm3; density= 11,3g/cm3
WOOD: mass= 15g ; volumen= 20cm3 ;density= 0.75 g/cm3
MARBLE: mass=125g ; volumen= 48cm3 ;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.
Explain in detail the difference between ferrous and non-ferrous metals. A metal is ferreous when it is made of iron and other metals. A metal is non-ferrous when it is not made of iron.
Define the terms ductile, malleable and corrosion resistant. Ductility is the ability of a material to deform, usually by stretching along its length. Malleable is the amount of hammering, pressing and shaping a material can take without breaking. Corrosion resistant means that a metal can't rust.
Suggest a use for: Mild Steel, stainless steel, Aluminium, Copper, Brass & Lead. Mild Steel: Stainless steel: Knife, spoon... Aluminium:Planes Cooper:Wires Brass: Medall lead:bullets

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ACTIVITIES Nº7.
1.- Make a mind-map on a card about A TECHNICAL MATERIALS and its: properties, uses, object, types, tools, etc.

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ACTIVITIES Nº8.
1.- Find out and draw three types of MATERIALS JOINTS.
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ACTIVITIES Nº9.
1.- Make a presentation of the comparition of two types of metals. Similar to this:

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ACTIVITIES Nº10.

1.- Make a REPORT of a tool similar to this:

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ACTIVITIES Nº11.

1.- Game: make out little cards with a name of a type of material on one and on the other one with its properties.

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ACTIVITIES Nº12.
1.- Listening: link ELLLO "SnowShoes"

NOW, ANSWER THE FOLOWEEN QUESTIONS.
1. Finish the conversation of this interview.
Jeff: So are they expensive?
Tim: They can be, but not too bad and you can rent them. Probably almost everywhere.
2. How does he describe “snow shoes”?
It's kind of hard to explain but it's kind of like a big paddle that you strap on to your boot. It is made out of kind of a webbing that spreads out your weight so that you can walk on snow, cause it distributes your weight out onto the snow.
3. Sketch a pair of snow shoes. Choose a suitable scale and list the materials that they are made.

4. What are Snow Shoes made of today?
They're made out of metals and good materials so they are pretty light now.
5. What are the heaviest metal and the lightest metal?
Heaviest-Lead Lightest-Aluminium
6. Describe the sports you like to practice or watch.

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2.- Listening: link on youtube (FiberGlass from Airbus of National Geographic.)

ACTIVITIES ABOUT THIS VIDEO:
1. Write True or False

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

2. Fill in the gaps

a. The outer ……………….. of the Airbus 380 must be superlight and ……………………
b. Fiber glass is about ………… to ten times the ………………… of steel
c. ……………….. resin is added afterwards
d. When it dries it ………………. the fibers together to create glass in its ………………. Form.
e. Fiber glass is even ……………… when combined in a composite with …………………
f. ……………….. 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?