Chapter 8 practice test. Flashcards
As a metal is heated:
a. energy is added to the structure
b. the atoms move further apart
c. the atoms vibrate more vigorously
d. the metal expands
e. all of the above
e. all of the above
The state of matter which exhibits the least amount of energy is:
a. solid
b. liquid
c. gas
d. quasi-liquid
e. none of the above
a. solid
Q 8-3 A problem occurring in weldrnents caused by the nonuniform heating produced by the welding operation is: a. porosity b. incomplete fusion c. distortion d. slag inclusions e. none of the above
c. distortion
Which of the following is not a method used to eliminate or reduce residual stresses?
a. vibratory stress relief
b. external restraint ‘
c. thermal stress relief
d. peening
e. annealing
b. external restraint
The type of alloying in which the alloy atoms are located in the spaces between the atoms of the parent metal is referred to as: a. atomic alloying b. substitutional alloying c. space alloying d. interstitial alloying e. none of the above
d. interstitial alloying
Rapid quenching of a steel from the austenitic range results in a hard, brittle structure known as: a. pearlite b. carbide c. cementite d. ironite e. martensite
e. martensite
Very slow cooling of steel may result in the production of a soft, ductile microstructure which as a lamellar appearance when viewed under high magnification. This structure is referred to as :
a. martensite
b. pearlite
c. bainite
d. femte
e. cementite
b. pearlite
When rapid cooling produces a martensitic structure, what sub-critical heat treatment may be applied to improve the ductility of the steel?
a. quenching
b. tempering
c. annealing
d. normalizing
e. none of the above
b. tempering
It is determined that a welding procedure is creating an excessive heat input. Which of the changes listed below would result in a reduction of the heat input?
a. decrease current
b. decrease voltage
c. increase travel speed
d. change from weave to stringer bead technique
e. all of the above
e. all of the above
The use of preheat will tend to:
a. result in a wider heat-affected zone
b. produce a lower heat-affected zone hardness
c. slow down the cooling rate
d. reduce the tendency to produce martensite in the heat-affected zone
e. all of the above
e. all of the above
Which of the following changes will warrant an addition or increase in the required preheat?
a. decreased carbon equivalent
b. increased carbon equivalent
c. increased base metal thickness
d. a and c above
e. b and c above
e. b and c above
What heat treatment is characterized by holding the part at the austenitizing temperature for
some time and then slow cooling in the furnace?
a. normalizing
b. quenching
c. annealing
d. tempering
e. stress relief
c. annealing
What heat treatment is characterized by holding the part at the austenitizing temperature for some time and then cooling in still air?
a. normalizing
b. quenching
c. annealing
d. tempering
e. stress relief
a. normalizing
Steel heated above the lower transformation temperature (Al,) will change microstructural
alignment. This temperature is?
a. 13330F
b. 9330 F
c. 15600F
d. 36000 C
e. none of. the above
a. 13330F
Atoms in the solid (frozen) state
a. have a specific “home” position
b. have no distinct structure
c. are essentially futed in a definite structured position
d. a and c above
e. none of the above
d. a and c above