Smart materials (1)

Complete the definitions (1-8) below with the highlighted words in the text.

1.	An __________ is something medical that is put inside the body, for example - a heart valve.
2.	You need a good __________ to think of new and interesting ideas.
3.	The ‘__________’ means the first or earliest.
4.	__________ are materials made from mixing two metals.
5.	To ‘__________’means to become bigger.
6.	To ‘__________’ means to change because something else happens.
7.	The __________ is everything around a person or thing.
8.	To ‘__________’ means to make smaller.

(“Engineering” Workshop by Lindsey White, OUP; Unit 6, pg.7, ex.4)

6. Answer the following questions to the text:

1. How many types of smart materials are there?

2. Which type appeared first?

3. Why are metal alloys expensive?

4. Why do these materials change their shape?

5. What does medicine use these materials for?

6. What are the spheres these materials widely used in?

7. Why are these materials called “smart”?

7. Match the following words:

implant imagination body alloys mixture shape materials(x2) inside uses

	patient’s				metal
	shape memory				possible
	put				original
	expensive				medical
	human				smart

8. Fill in the gaps in the following sentences with a suitable word:

1. Brass is an ______________ of copper and zinc.

2. Brass doesn’t _____________ to water.

3. Smart materials can return to their ________________ shape.

4. Metals ______________ when they are heated.

5. ____________________ is the ability to create pictures in your mind.

6. Smart materials are called so, because they react to changes in their ________________.

7. Medical ______________ is usually _______________ and put inside the patient’s body.

8. Bricks are hold together with the help of a __________________ of cement and water.

9. Smart materials have good shape ________________.

10. “Smart materials” is the human _________________ of the twentieth century.

Check the knowledge of active vocabulary from this part with the help of “ACTIVE VOCABULARY” section.

Part II

Read the following text and fill in the gaps. Use the words given in boxes:

temperature materials types magnetic properties

Smart materials are (1) __________ that have one or more (2) __________ that can be significantly changed in a controlled manner by external stimulation, such as stress, (3)__________, moisture, pH, electric or (4) __________ fields.

There are different (5) __________ of smart materials, some of which are already common. Some examples are as following:

environment produce changes field from shape

• Piezoelectric materials are materials that (6) __________ a voltage when stress is applied. Suitably designed structures made (7) __________ these materials can bent, expand or contract when a voltage is applied.
• Shape memory alloys and shape memory polymers are thermo-responsive materials where deformation can be seen in case of temperature (8) __________.
• Magnetic shape memory alloys are materials that change their (9) __________ in response to a significant change in the magnetic (10) __________.
• pH-sensitive polymers are materials which collapse when the pH of the (11) __________ changes.
• Temperature-responsive polymers are materials which changes depend on temperature.

pressure metal opacity colour sunlight response electrical

• Halochromic materials are commonly materials that change their colour as a result of changing acidity. One suggested application is for paints that can change (12) __________ to indicate corrosion in the (13) __________ underneath them.
• Chromogenic systems change colour in response to (14) __________, optical or thermal changes. These include electrochromic materials, which change their colour or (15) __________ on the application of a voltage (e.g. liquid crystal displays), thermochromic materials change in colour depending on their temperature, and photochromic materials, which change colour in response to light - for example, light sensitive sunglasses darken when used in bright (16) __________.
• Non-Newtonian fluid is a liquid which changes its viscosity in response to an applied shear rate (to shear = to become twisted or break under pressure). In other words the liquid will change its viscosity in (17) __________ to some sort of force or (18) __________.
• Ferrofluid
• Photomechanical Materials change shape under exposure to light.

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