Introduction

This unit deals with applications of a new metal alloy (a combination of two elements). As the name suggests, this alloy can remember its shape (form) and will always return to it after heating.

1 Listening

A research engineer is talking about the applications of a new type of metal alloy. The table below shows three applications and should show the sequence of actions and reactions. As you listen, compete the table.

2 Presentation

During his talk, the Research Engineer expressed the concepts of CAUSE and EFFECT in three different ways:

a. When clause

e.g. When the piston is cold, the coil contracts.

b. Verbs linking the cause to the effect

e.g. Heat causes it to expand. (cause something to happen)

This makes the fan close. (make something happen)

Cold weather leads to expansion. (lead to

results in (result in something)

brings about (bring about

с. Adverbs linking the cause to the effect

e.g. The spring contracts and so allows the fan to operate.

therefore

consequently

thus

as a result

3 Controlled Practice

A. Use the above three ways of expressing cause and effect, and the table from Section 1, to finish these sentences.

1. ________ the coffee machine ________ ________ ________ ________,

the SMA actuator ________ the valve and______ the water

2. ___________ it______________, the spring ________.This________ the

fan ________ ________ and ________ the car_________________

3. In warm weather, the spring ________ and ________ the fan ________. This ________ the car _________________________

B. Use the diagram of a process cycle to complete the description:

Description of process cycle

__________the temperature__________,___________________ and __________

_____________________. This _________the heater to be switched off and

________________________________. In time, the metal contracts and

__________broken. The broken contact _________the heater ________________

_____________________and __________the cycle starts again.

4 Transfer

Think of other applications of Shape Memory Alloys and explain how they would work. E.g. Air conditioning systems

An electric toaster

An electric iron

etc.

5 Word Check

PROCESS VERBS

to deform — to change shape

to contract — to get smaller

to expand — to get bigger

to supply — to give, provide

to give off — to transmit into the atmosphere

to warm (up) — to become warm, cf. to heat

to cool (down) — to become cold

to dump — to drop, to empty the contents

to fit — to attach, to fix

DEVICES

a valve — a control which opens and closes

an actuator — a control which activates (something)

a fan — a device which blows out hot or cold air

unit 5 What is a Transistor?

(properties)