EPRI: Materials – Questions & Verified Solutions
Ferrous Alloys ✔️Ans -What includes iron and at least 50% iron
alloys?
Degradation ✔️Ans -What is damage caused over time to
components/ materials by a range of physical processes à resulting in
component failure?
Additional Nuclear Safety Issues ✔️Ans -What type of material
degradation led to the following consequences:
-costly outages,
-increase regulatory oversight
-create losses due to the impact of cost, time, and effort of station
management and personnel
Corrosion of piping walls ✔️Ans -What type of material
degradation led to the following consequences:
-allow the release of high energy fluids
-challenge the performance of nuclear safety-related systems
-significant personnel injury
Degradation of RC Pressure Boundary ✔️Ans -What type of
material degradation led to the following consequences:
-release of radioactive materials
-reducing the defense-in-depth for the plant workers and the general public
from exposure to radiation
-LOCA (Loss of Coolant Accident)
-loss of core cooling which increases risk of fuel damage
Degradation of RC Pressure Boundary ✔️Ans -The following are
examples of which type of material degradation consequence:
-VC Summer: hot leg RC piping leakage (Nov '00)
-Davis Besse: head wastage (Feb '02)
-Tsuruga (Japan): pressurizer relief valve leak (Sep '03)
-South TX Project: bottom mounted inst. Nozzle leak (April '03)
-Quad Cities: steam dryer degradation (July '02)
,Stress Corrosion Cracking (SCC) ✔️Ans -What can occur under
certain conditions of high tensile stress, a corrosive environment, and
susceptible materials?
Metals ✔️Ans -What has a class of elements and/or compounds
which exhibit attributes:
-Lustrous appearance
-Opaque
-Good conductor of heat and electricity
-Can be deformed to some extent before breaking
-Oxidizes, that is, give up electrons in chemical reactions
-Solid at room temperature (mercury is an exception)
-High melting point
-Not normally found in a pure state, but must be refined from an ore
Metal ✔️Ans -What is a collection of millions of crystals composed
of different atoms held together by metallic bonds?
Alloys ✔️Ans -What is a mixture of two or more materials, one of
which is a metal?
Alloys ✔️Ans -What enhances metal properties by:
-Increase strength and/or hardness
-Enhance ductility
-Increase corrosion resistance
-Enhance strength and/or machinability
-Increase wear resistance
Alloys ✔️Ans -What is stronger than pure metals?
Alloys ✔️Ans -What has reduced electrical and thermal
conductivity?
Steel ✔️Ans -_______ is an alloy of iron and carbon
Iron ✔️Ans -Ferrous is latin for?
Ferrous Alloys ✔️Ans -What alloy is dependent on catching the key
element carbon?
, Ferrous Alloys ✔️Ans -cast iron, wrought iron, steel and stainless
steel are all examples of what alloy?
Non-ferrous Alloys ✔️Ans -What is composed predominantly of
elements other than iron?
Non-ferrous Alloys ✔️Ans -·copper-based alloys, cobalt-based
alloys (Stellites), zirconium based (Zircalloys), nickel based (InconelTM) are
all examples of what alloy?
Non-ferrous Alloys ✔️Ans -examples of what alloy are commonly
used in nuclear power plants?
Strength ✔️Ans -What is the measure of the ability of a material to
SUPPORT an applied load (also ability to resist deformation)?
Ductility ✔️Ans -What is the ability of a material to deform easily
on application of tensile force?
Ductility ✔️Ans -What is the ability of a material to withstand
plastic deformation without rupture?
Ductility ✔️Ans -What is the ability of a material to undergo plastic
deformation prior to fracture?
Hardness ✔️Ans -What is the property of a material that enables it
to resist plastic deformation, penetration, indentation, and scratching?
Machinability ✔️Ans -How metal reacts to mechanical deformation
by removing CHIPS with respect to amount of metal effectively removed and
surface finish attainable is?
Machinability ✔️Ans -The mechanical properties of the metal will
be the factors that influence the _____________ of a metal
Conductivity ✔️Ans -What is the property of conducting heat or
electric current?
Ferrous Alloys ✔️Ans -What includes iron and at least 50% iron
alloys?
Degradation ✔️Ans -What is damage caused over time to
components/ materials by a range of physical processes à resulting in
component failure?
Additional Nuclear Safety Issues ✔️Ans -What type of material
degradation led to the following consequences:
-costly outages,
-increase regulatory oversight
-create losses due to the impact of cost, time, and effort of station
management and personnel
Corrosion of piping walls ✔️Ans -What type of material
degradation led to the following consequences:
-allow the release of high energy fluids
-challenge the performance of nuclear safety-related systems
-significant personnel injury
Degradation of RC Pressure Boundary ✔️Ans -What type of
material degradation led to the following consequences:
-release of radioactive materials
-reducing the defense-in-depth for the plant workers and the general public
from exposure to radiation
-LOCA (Loss of Coolant Accident)
-loss of core cooling which increases risk of fuel damage
Degradation of RC Pressure Boundary ✔️Ans -The following are
examples of which type of material degradation consequence:
-VC Summer: hot leg RC piping leakage (Nov '00)
-Davis Besse: head wastage (Feb '02)
-Tsuruga (Japan): pressurizer relief valve leak (Sep '03)
-South TX Project: bottom mounted inst. Nozzle leak (April '03)
-Quad Cities: steam dryer degradation (July '02)
,Stress Corrosion Cracking (SCC) ✔️Ans -What can occur under
certain conditions of high tensile stress, a corrosive environment, and
susceptible materials?
Metals ✔️Ans -What has a class of elements and/or compounds
which exhibit attributes:
-Lustrous appearance
-Opaque
-Good conductor of heat and electricity
-Can be deformed to some extent before breaking
-Oxidizes, that is, give up electrons in chemical reactions
-Solid at room temperature (mercury is an exception)
-High melting point
-Not normally found in a pure state, but must be refined from an ore
Metal ✔️Ans -What is a collection of millions of crystals composed
of different atoms held together by metallic bonds?
Alloys ✔️Ans -What is a mixture of two or more materials, one of
which is a metal?
Alloys ✔️Ans -What enhances metal properties by:
-Increase strength and/or hardness
-Enhance ductility
-Increase corrosion resistance
-Enhance strength and/or machinability
-Increase wear resistance
Alloys ✔️Ans -What is stronger than pure metals?
Alloys ✔️Ans -What has reduced electrical and thermal
conductivity?
Steel ✔️Ans -_______ is an alloy of iron and carbon
Iron ✔️Ans -Ferrous is latin for?
Ferrous Alloys ✔️Ans -What alloy is dependent on catching the key
element carbon?
, Ferrous Alloys ✔️Ans -cast iron, wrought iron, steel and stainless
steel are all examples of what alloy?
Non-ferrous Alloys ✔️Ans -What is composed predominantly of
elements other than iron?
Non-ferrous Alloys ✔️Ans -·copper-based alloys, cobalt-based
alloys (Stellites), zirconium based (Zircalloys), nickel based (InconelTM) are
all examples of what alloy?
Non-ferrous Alloys ✔️Ans -examples of what alloy are commonly
used in nuclear power plants?
Strength ✔️Ans -What is the measure of the ability of a material to
SUPPORT an applied load (also ability to resist deformation)?
Ductility ✔️Ans -What is the ability of a material to deform easily
on application of tensile force?
Ductility ✔️Ans -What is the ability of a material to withstand
plastic deformation without rupture?
Ductility ✔️Ans -What is the ability of a material to undergo plastic
deformation prior to fracture?
Hardness ✔️Ans -What is the property of a material that enables it
to resist plastic deformation, penetration, indentation, and scratching?
Machinability ✔️Ans -How metal reacts to mechanical deformation
by removing CHIPS with respect to amount of metal effectively removed and
surface finish attainable is?
Machinability ✔️Ans -The mechanical properties of the metal will
be the factors that influence the _____________ of a metal
Conductivity ✔️Ans -What is the property of conducting heat or
electric current?
