Deck 3: Mechanical Properties of Materials

Question 1

Which of the following are the three basic types of static stresses to which a material can be subjected (three correct answers):

A)compression
B)hardness
C)reduction in area
D)shear
E)tensile
F)true stress
G)Yield

Answer 1

compression
shear
tensile

Question 2

Which one of the following is the correct definition of ultimate tensile strength, as derived from the results of a tensile test on a metal specimen:

A)the stress encountered when the stress-strain curve transforms from elastic to plastic behavior
B)the maximum load divided by the final area of the specimen
C)the maximum load divided by the original area of the specimen
D)the stress observed when the specimen finally fails

Answer 2

the maximum load divided by the original area of the specimen

Question 3

If engineering stress and true stress were measured simultaneously during a tensile test, which would have the higher value:

A)engineering stress
B)true stress

Answer 3

true stress

Question 4

If engineering strain and true strain were measured simultaneously during a tensile test, which would have the higher value:

A)engineering strain
B)true strain

Question 5

The plastic region of the stress-strain curve for a metal is characterized by a proportional relationship between stress and strain:

Question 6

Hooke's Law defines which one of the following regions of the stress strain relationship for engineering materials:

A)elastic region
B)plastic region
C)neither

Question 7

The modulus of elasticity is also known as which one of the following:

A)elastic limit
B)strain hardening exponent
C)strength coefficient
D)Young's modulus

Question 8

Which one of the following materials has the highest modulus of elasticity:

A)aluminum
B)diamond
C)steel
D)titanium
E)tungsten

Question 9

The flow curve describes the property of metals known as which one of the following:

A)ductility
B)engineering strain
C)fracture stress
D)strain hardening
E)tensile strength

Question 10

Which one of the following types of stress strain relationship best describes the behavior of brittle materials such as ceramics and thermosetting plastics:

A)elastic and perfectly plastic
B)elastic and strain hardening
C)perfectly elastic
D)none of the above

Question 11

Which one of the following types of stress strain relationship best describes the behavior of most metals at room temperature:

A)elastic and perfectly plastic
B)elastic and strain hardening
C)perfectly elastic
D)none of the above

Question 12

Which one of the following types of stress strain relationship best describes the behavior of metals at temperatures above their respective recrystallization points:

A)elastic and perfectly plastic
B)elastic and strain hardening
C)perfectly elastic
D)none of the above

Question 13

The transverse rupture strength is a property usually associated with which one of the following material types:

A)ceramics
B)metals
C)plastics
D)rubber

Question 14

The shear strength of a metal is commonly determined in which one of the following tests:

A)bending test
B)compression test
C)flexure test
D)tensile test
E)torsion test

Question 15

The shear strength of a metal is usually

A)greater than
B)less than its tensile strength

Question 16

Hardness is best defined as which one of the following:

A)energy absorbed by a material when an object strikes its surface
B)resistance to bending
C)resistance to permanent indentation
D)resistance to scratching

Question 17

Most hardness tests involve pressing a hard object into the surface of a test specimen and measuring the resulting indentation or its effect:

Question 18

Which one of the following materials has the highest hardness:

A)alumina ceramic
B)gray cast iron
C)hardened tool steel
D)high carbon steel
E)polystyrene

Question 19

The formation of new strain-free grains in a metal that has been heated to an elevated temperature is called which one of the following:

A)hot hardness
B)recrystallization
C)strain hardening
D)strain softening

Question 20

Viscosity can be defined as the ease with which a fluid flows:

Question 21

A Newtonian fluid is a fluid best defined by which one of the following:

A)its viscosity decreases as shear rate increases
B)its viscosity decreases as temperature increases
C)its viscosity increases as shear rate increases
D)its viscosity increases as temperature increases
E)its viscosity remains constant as shear rate changes
F)its viscosity remains constant as temperature changes

Question 22

Viscoelasticity can be defined as the property of a material that determines the strain it experiences when subjected to combinations of stress and temperature over time: