module 2

Question 1

have been conveniently grouped into three basic categories:
metals, ceramics, and polymers, a scheme based primarily on chemical makeup and
atomic structure. Most materials fall into one distinct grouping or another. In addition,
there are the composites, which are engineered combinations of two or more different
materials.

Answer 1

Solid materials

Question 2

are opaque, lustrous elements that are good conductors of heat and

electricity. Strong yet deformable under applied mechanical loads; opaque to light (shiny if
polished) .

Answer 2

Metals

Question 3

These are inorganic compounds, and usually made either of oxides, carbides,
nitrides, or silicates of metals. These are inorganic compounds, and usually made either of oxides, carbides,
nitrides, or silicates of metals. These materials are usually insulators to heat and electricity.

Answer 3

Ceramics

Question 4

are materials made of long, repeating chains of molecules. The materials have unique properties, depending on the type of molecules being
bonded and how they are bonded.

Answer 4

Polymers

Question 5

is a combination of two materials with different physical and
chemical properties. The reason for their use over traditional materials is because they improve the
properties of their base materials and are applicable in many situations.

Answer 5

Composites

Question 6

used in high-technology
applications, such as semiconductors, biomaterials, smart materials, and
nanoengineered materials.

Answer 6

advanced materials

Question 7

have electrical properties that are intermediate between those of
electrical conductors (i.e., metals and metal alloys) and insulators (i.e., ceramics
and polymers). have made possible the advent of integrated circuitry that has
totally revolutionized the electronics and computer industries (not to mention our
lives) over the last four decades.

Answer 7

Semiconductors

Question 8

are employed in components implanted into the human body to
replace diseased or damaged body parts. These materials must not produce toxic substances and must be compatible with
body tissues (i.e., must not cause adverse biological reactions).

Answer 8

Biomaterials

Question 9

are a group of new and state-of-the-art materials
now being developed that will have a significant influence on many of our
technologies.

Answer 9

Smart Materials

Question 10

One new material class that has fascinating properties and tremendous
technological promise, which may be any one of the four basic
types—metals, ceramics, polymers, or composites.

Answer 10

Nanomaterials

Question 11

consists some
type of sensor (detects an input) and an actuator (performs responsive and adaptive
function).

Answer 11

Smart/Intelligent material system

Question 12

may be called upon to change shape, position, natural frequency,
mechanical characteristics in response to changes in temperature, electric/magnetic
fields, moisture, pH, etc.

Answer 12

Actuators

Question 13

Four types of materials used as actuators:

Answer 13

Shape memory alloys, Piezo-electric

ceramics, Magnetostrictive materials, Electro-/Magneto-rheological fluids.

Question 14

Materials / Devices used as sensors:

Answer 14

Optical fibers, Piezo-electric materials, Micro-electro-
mechanical systems (MEMS), etc.