Mechanical Properties of Metals

Question 1

Metals are known to be:

Answer 1

Malleable & Ductile
High density
High Melting Point
High Thermal Conductivity
High Electric Conductivity

Question 2

how much force an
object can withstand without bending or breaking (compression, tension, & shear)

Answer 2

STRENGTH

Question 3

refers to a material’s
response to tensile stress, or its
ability to be stretched, rolled or extruded without breaking.

Answer 3

Ductility

Question 4

refers to compressive stress, as in flattening.

Answer 4

Malleability

Question 5

represents an ideal
balance between strength and ductility. The toughest metals are those that can absorb the highest amounts of energy before fracturing

Answer 5

Toughness

Question 6

is a measure of a
part’s ability to undergo repeated,
cyclical stress without fracturing or
permanently deforming.

Answer 6

Fatigue resistance

Question 6

A material’s power to
resist a permanent change in shape when acted upon by an external force

Answer 6

Hardness

Question 7

FCC Mechanical Properties

Answer 7

Low young modulus
Low yield strength
Low hardness
Good ductility and high ability for forming.

Question 8

BCC Mechanical properties

Answer 8

High yield strength
High young modulus
High hardness
High tensile strength
Limited ability to forming

Question 9

HCP Mechanical properties

Answer 9

Brittle
Low yield strength
Inability to forming

Question 10

Key mechanical design properties are

Answer 10

stiffness, strength, hardness, ductility, and toughness.

Question 10

A specimen is deformed, usually to
fracture, with a gradually increasing tensile load that is applied uniaxially along the long axis of a specimen.

Answer 10

Tension Tests

Question 11

conducted in a manner similar to the tensile test, except that the force is compressive and the specimen contracts along
the direction of the stress.

Answer 11

Compression stress–strain tests

Question 12

a variation of pure shear in which a
structural member is twisted in the manner of torsional forces produce a rotational motion about
the longitudinal axis of one end of the member relative to the other end.

Answer 12

Torsion

Question 13

a function of the orientations of the
planes upon which the stresses are taken to act.

Answer 13

stress state

Question 14

non-permanent, which means that when the applied load is released, the piece returns to its original
shape.

Answer 14

Elastic deformation

Question 15

The stress necessary to
continue plastic deformation
in metals increases to a
maximum, point M and then
decreases to the eventual
fracture, point F. Unit Mpa
or psi

Answer 15

Tensile Strength (TS)

Question 16

It is a measure of the degree of plastic deformation that has been
sustained at fracture

Answer 16

DUCTILITY

Question 17

Knowledge of the ductility of materials is important for at
least two reasons.

Answer 17

1.) It indicates to a designer the degree to which a structure will deform plastically before before fracture

2.) It specifies the degree of allowable deformation during fabrication operations.

Question 18

Metal that experiences
very little or no plastic deformation upon fracture

Answer 18

Brittle

Question 19

Is the capacity of a material to
absorb energy when it is deformed elastically and then, upon unloading, to have this energy recovered.

Answer 19

Resilience

Question 20

is the ability of a material to absorb energy and plastically deform before fracturing

Answer 20

Toughness

Question 21

which is a measure of a material’s resistance to localized plastic deformation (e.g., a small dent or
a scratch).

Answer 21

Hardness