6 TESTS

Assessment

� What are ferrous metals? Name three and givetheir percentages of carbon.

� What are the principal properties of steel? And ofcast iron? What are these metals used for?

� What are the most important properties ofcopper? Name at least two alloys made with thismetal. What other components are used to makeeach alloy?

� What are the most important characteristics ofaluminium? And of lead?

Think about the following: colour / resistant tocorrosion / hard or soft / high or low density /malleable / ductile / plastic / heavy or light /thermal conductor or insulator / electricalconductor or insulator.

� What is metal casting?

� What metals would you use to make thefollowing objects?

a) A drink can

b) The casing for a household appliance

c) A radiator

d) A bracelet

e) A food tin

f) A thermometer

g) A pipe

h) A wire

i) A window frame

� Classify these ways of joining metal as temporaryor permanent: soft solder, screw, threaded staybolt, rivet, keyed joint and adhesives.

Write the name of two tools used for each of thefollowing functions:

a) for marking and cutting

b) for drilling

c) for shaping and turning

d) for finishing

e) for securing pieces.

Name Surname(s)

Year Date Mark

PHOTOCOPIABLE RESOURCE / © Oxford University Press España S. A. Technologies I

6 TESTS

Assessment

� Ferrous metals are those metals which mainly containiron. They include pure iron (carbon concentration0.008%-0.03%), steel (carbon concentration 0.03%-1.76%)and cast iron (carbon concentration 1.76%-6.67%).

� Steel is a very hard, tough metal which is highly resistantto traction. It is used in construction (tubes, beams, tools,etc.) and for making the hulls of boats, machinery, thebodywork of cars, bearings, tools, etc.

Cast iron is extremely hard and very resistant to wear. It isused to make various machine parts, engine casings, gearassemblies, pistons, street lamps, drainhole covers, etc.

� Copper presents high thermal and electrical conductivity.It is also very malleable and ductile. It is a soft metal,reddish in colour and shiny. It oxidises easily.

Copper alloys include: brass, bronze, nickel silver andcupronickel. Brass is an alloy of copper and zinc; bronze,of copper and tin; nickel silver, of copper, nickel, zinc andtin; and cupronickel, of copper and nickel.

� Aluminium is a silvery white metal which is very resistantto corrosion. It is very soft, has a low density and is verymalleable and ductile. It is a very good thermal andelectrical conductor.

Lead is a silvery grey metal. It is soft, heavy, very plasticand malleable. It is a very good thermal and electricalconductor.

� Casting consists of pouring melted metal into a containerof the desired shape. The metal is left to cool until it hassolidified, and then it is extracted from the container(called a mould).

� a) A drink can: aluminium.

b) The casing for a household appliance: steel.

c) A radiator: copper, aluminium.

d) A bracelet: brass, silver or gold.

e) A food tin: tin plate.

f) A thermometer: mercury.

g) A pipe: copper.

h) A wire: copper, aluminium.

i) A window frame: aluminium.

� Temporary: screw, threaded stay bolt and keyed joint.

Permanent: soft solder, rivet and adhesives.

a) metal shears, scriber, odd-leg callipers, compass,guillotine, punch press, hacksaw

b) awl, drill

c) chisel, milling machine, lathe

d) file, scraper, sander, grinder

e) vice, clamp, tongs, pliers

© Oxford University Press España S. A. Technologies I

Answer key