EXAM 1

Question 1

Does alloying affect the properties of pure metals?

Answer 1

Yes

Question 2

What is a ferrous metal?

Answer 2

An alloy with iron (Fe) as the major alloying element

Question 3

What is metallurgy?

Answer 3

the study of metals

Question 4

What is a nonferrous metal?

Answer 4

A pure metal or alloy that does not include iron as the major alloying element

Question 5

Explain the difference between a metal and an alloy.

Answer 5

Metals are pure chemical elements. Alloys are materials that have metallic properties and are composed of two or more chemical elements. Alloys are used to improve the properties of pure metals.

Question 6

Explain the differences between cast and wrought metals.

Answer 6

Cast metals are produced from molten metal solidifying in a mold cavity. Wrought metals are worked into finished forms using processes such as drawing, extruding, rolling, and pressing. Cast metals are less dense than wrought metals.

Question 7

What is density?

Answer 7

the mass per unit of volume of a material

Question 8

What is absolute zero?

Answer 8

A theoretical condition at which no heat is present

Question 9

What is a temperature indicating crayon?

Answer 9

A marker made from material that melts at a certain temperature

Question 10

Explain the difference between electrical conductivity and electrical resistivity.

Answer 10

Electrical conductivity measures a material’s ability to conduct an electric current. Resistivity measures how strongly a material opposes electric current. It is how conductivity is expressed.

Question 11

What is mechanical testing used for?

Answer 11

developing design data, maintaining quality control, assisting in alloy development programs, and providing data in failure analysis

Question 12

The gauge length of a test specimen is always ____________ the distance between the shoulders of the test specimen.

Answer 12

less than

Question 13

What is the point of failure?

Answer 13

The point of failure is the point at which fracture occurs.

Question 14

What is the temp at which the impact behavior of a metal changes from ductile to brittle in the presence of a stress raiser?

Answer 14

Nil Ductility Transition Temperature

Question 15

Explain the differences between dynamic and static testing.

Answer 15

In dynamic tests the load is applied very rapidly and may also be applied continuously or repeatedly.
In static testing the load is applied slowly enough so that the speed of testing has a negligible effect on the results.

Question 16

True or False:

Most metals exhibit one of three unit cell types.

Answer 16

True

Question 17

What is an isotope?

Answer 17

A form of a chemical element with a different number of neutrons.

Question 18

The _______ unit cell is a cube with an atom at each corner, one in the center, and one in the center of each side of the cube.

Answer 18

Face-Centered Cubic unit cell (FCC)

Question 19

What is atomic structure?

Answer 19

Atomic structure refers to the organization of atoms and their basic parts.

Question 20

What is an allotropic metal?

Answer 20

a metal that exhibits more than one unit cell structure

Question 21

Explain how the crystal structure of an alloy is determined.

Answer 21

The crystal structure of an alloy is determined by the proportions of alloying chemical elements present.

Question 22

What is the point at which strain occurs without an increase in stress?

Answer 22

the yield point

Question 23

Explain the relationship between a space lattice and a unit cell.

Answer 23

A space lattice is a regular array of points produced by lines connected through the points. A unit cell is the smallest arrangement of atoms that repeats itself through the space lattice. As the number of atoms per lattice point increases, the unit cell becomes more complex.

Question 24

TRUE OR FALSE:

Castings are usually more dense than wrought metals of similar composition.

Answer 24

FALSE

Question 25

What is the extent to which a surface deviates from the ideal radiative surface?

Answer 25

Emissivity