Unit 1
| Assignment III
| 1 – b; 2 – d; 3 – a; 4 – f; 5 – e; 6 – c.
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| Assignment IV:
| 1 – F; 2 – T; 3 – F; 4 – T; 5 – F; 6 – T.
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Unit 2
| Assignment III:
| 1 – forging; 2 – rolling; 3 – extrusion; 4 – rolling, extrusion, drawing, forging;
5 – sheet-metal forming; 6 – drawing; 7 – two-closed die; 8 – sheet-metal forming; 9 – extrusion.
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Unit 3
| Assignment III:
| 1 – feature; 2 – porosity; 3 – grain; 4 – segregation; 5 – alloy; 6 – strain; 7 – workpiece; 8 – flaw.
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| Assignment IV:
| 1. The grains of the metal become greatly elongated in the direction of flow.
2. The ability of a metal to resist thinning and fracture plays an important role in alloy selection.
3. Copper and aluminium are more ductile in forming operations than other metals.
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Unit 4
Assignment V:
| 2)
| Application
| Cause
| Primary effect
| Secondary effect
| Tertiary effect
|
| 1.Piston
| Piston cold
| Coil contracts
| Piston doesn’t move
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| Piston hot
| Coil expands
| Piston moves up
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| 2.Coffee machine
| Reaches certain temperature
| SMA actuator opens valve
| Water is dumped onto coffee
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| 3.Cooling fan in car
| Cold weather
| Spring expands
| The fan closes down
| Car warms up
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| Warm weather
| Spring contracts
| The fan operates
| Car cools down
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3) Possible answers:
1. When the coffee machine reaches a certain temperature, the SMA actuator opens the valve and so the water is dumped onto the coffee.
2. When it is cold the spring expands. This makes the fan close down and so the car warms up.
3. In warm weather, the spring contracts and therefore the fan operates. This causes the car to cool down.
4) Possible answer:
When the temperature rises the metal expands and consequently the contact is made. This causes the heater to be switched off and so the temperature drops. In time, the metal contracts and thus the contract is broken. The broken contact causes the heater to be switched on and so the cycle starts again.
Unit 5
| Assignment III:
| 1- e; 2 – c; 3 – a; 4 – g; 5 – b; 6 – d; 7 – f.
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| Assignment IV:
| 1 – T; 2 – F; 3 – T; 4 – F; 5 – F; 6 – T.
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| Assignment V:
| 1)1 – f; 2 – c; 3 – g; 4 – a; 5 – d; 6 – b; 7 – h; 8 – e.
2) Student A – pitting corrosion; Student B – microbiological corrosion.
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Written Test 1 “Metals”
| Vocabulary
| A)1 - b; 2 - g; 3 - i; 4 - a; 5 - d; 6 - h; 7 - e; 8 - f; 9 - j; 10 - c.
B) 1 - b; 2 - b; 3 - a; 4 - a.
C) 1 - f; 2 - a; 3 - e; 4 - b; 5 - c; 6 - d.
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| Reading
| A) 1 - d; 2 - f; 3 - h; 4 - b; 5 - e; 6 - i; 7 - a; 8 - j; 9 - c; 10 - g.
B) 1 - F; 2 - T; 3 - F; 4 - T; 5 - F; 6 - T; 7 - T; 8 - T; 9 - F; 10 - F.
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Written Test 2 “Metals”
| Vocabulary
| A)1 - b; 2 - a; 3 - c; 4 - c; 5 - b; 6 - b.
B)1 - c; 2 - h; 3 - a; 4 - k; 5 - f; 6 - b; 7 - n; 8 - e; 9 - m; 10 - g; 11 - l; 12 - i; 13 - j; 14 - d.
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| Reading
| A) 1 - f; 2 - c; 3 - h; 4 - a; 5 - i; 6 - g; 7 - k; 8 - e; 9 - b; 10 - j.
B) 1 - F; 2 - F; 3 - T; 4 - F; 5 - T; 6 - F; 7 - T; 8 - T; 9 - F; 10 - T.
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Written Test 3 “Metals”
| Vocabulary
| А)1 - b; 2 - c; 3 - a; 4 - c; 5 - d; 6 - b.
B)1 - m; 2 - i; 3 - g; 4 - c; 5 - b; 6 - k; 7 - e; 8 - j; 9 - a; 10 - h; 11 - f; 12 - d; 13 - n; 14 - l.
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| Reading
| Possible answers:
A) 1. It is more rust-resistant than steel and welds more easily.
2. Higher concentrations of carbon or lower temperatures will produce cementite.
3. Carbon and other elements act as a hardening agent, preventing dislocations in the iron atom crystal lattice from sliding past one another.
4. The carbon content in steel is between 0.2% and 2.14% by weight (C: 110–10Fe), depending on grade.
5. Yes, it is. The steel with increased carbon content is more brittle.
6. Today, steel is one of the most common materials in the world and is a major component in buildings, infrastructure, tools, ships, automobiles, machines, and appliances.
7. In the mid-19th century steel became a relatively inexpensive mass-produced material.
8. No, they were not. Historically iron and steel were separate products.
9. Varying the amount of alloying elements and form of their presence in the steel (solute elements, precipitated phase) controls qualities such as the hardness, ductility, and tensile strength of the resulting steel.
10. Cast iron is an alloy with higher carbon content than iron.
B) 1. Alloying changes the grain structure and properties of metals.
2. Cold working makes metal harder and stronger, but some metals have a limit to the strain.
3. The wall thickness of the aluminium can is determined by the gap between the ram and the die.
4. Rolling is the most general metalworking process and sheet is the most common rolled product.
5. Hot working of metal improves its mechanical properties and eliminates porosity and inner flaws.
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