Properties of Material

Question 1

Engineering Materials

Answer 1

metals, polymers, elastomers, ceramics, glasses, hybrids

Question 2

have relatively high elastic moduli

Answer 2

metals

Question 3

have high moduli but brittle

Answer 3

ceramics

Question 4

non-crystalline solids

Answer 4

glasses

Question 5

have moduli that are low, roughly 50 times lower than metals but can be nearly as strong as metals

Answer 5

polymers

Question 6

long-chain polymers above their glass-transition temperature

Answer 6

elastomers

Question 7

combination of two or more materials in a predetermined configuration and scale

Answer 7

hybrids

Question 8

most - when pure - are soft and can be easily deformed; can be made strong by alloying and by mechanical and heat treatment but remain ductile

Answer 8

metals

Question 9

no ductility; low tolerance for stress concentrations or for high-contact stresses

Answer 9

ceramics

Question 10

most common glasses

Answer 10

soda-lime, borosilicate glasses

Question 11

hard, brittle, and corrosion-resistant

Answer 11

ceramics & glasses

Question 12

ductile, tough, and good thermal and electrical conductors

Answer 12

metals

Question 13

light, easily shaped, and electrical insulators

Answer 13

polymers

Question 14

have the ability to deform elastically to large stains

Answer 14

elastomers

Question 15

ability of a material to stand up to forces being applied without it bending, breaking, shattering, or deforming in any way

Answer 15

hardness

Question 16

property of resisting penetration or permanent distortion

Answer 16

hardness

Question 17

the ability of a material to withstand cracks; characteristic of a material that does not break or shatter when receiving a blow or under a sudden shock

Answer 17

toughness

Question 18

affected by the rate of loading, temperature, and notch effect

Answer 18

toughness

Question 19

affected by the strength and plasticity of the material

Answer 19

hardness

Question 20

property of returning to the original shape when causing the change of shape is removed

Answer 20

elasticity

Question 21

ability of a material to absorb force and flex into different directions, returning to its original position

Answer 21

elasticity

Question 22

reached when the graph line in force-extension graph starts to curve

Answer 22

elastic limit

Question 23

ability of a material to be changed in shape permanently

Answer 23

plasticity

Question 24

ability of a material to be reshaped in all directions without cracking; easy to beat into a thin sheet

Answer 24

malleability

Question 25

property of metals which allows them to be bent or permanently distorted without rupture

Answer 25

malleability

Question 26

property of metals which allows them to be drawn out without breaking

Answer 26

ductility

Question 27

ability of a material to change shape usually by stretching along its length; how easily a material can be worked

Answer 27

ductility

Question 28

ability of a material to resist applied stress before failure without deformation

Answer 28

stiffness

Question 29

resistance to elastic deformation; ability to resist bending

Answer 29

stiffness

Question 30

ability of a metal to become liquid by the application of heat

Answer 30

fusibility

Question 31

property which enables a metal to carry heat or electricity; important for fusion and to control expansion and contraction

Answer 31

conductivity

Question 32

reactions produced in metals as the result of heating or cooling

Answer 32

contraction and expansion

Question 33

weight of a unit volume of a material; important consideration for weight and balance

Answer 33

density

Question 34

property of a metal which allows little bending or deformation without shattering; not a very desirable property

Answer 34

brittleness

Question 35

necessary in sheet metal that is worked into curved shapes such as cowlings, fairings, or wingtips

Answer 35

malleable

Question 36

greatly preferred for aircraft use because of their case of forming and resistance to failure under shock loads

Answer 36

ductility

Question 37

desirable property in aircraft metals

Answer 37

toughness

Question 38

important consideration when choosing a material to be used in the design of a part in order to maintain the proper weight and balance of the aircraft

Answer 38

density

Question 39

must be considered in conjunction with bonding, to eliminate radio interference

Answer 39

conductivity

Question 40

affect the design of welding jigs, castings, and tolerances

Answer 40

contraction and expansion