EPRI EF Nuclear Power Plant Materials
Certification Exam Questions and
Answers
Brittleness - Answers -The opposite of ductility. Brittle metals exhibit a small percentage
of elongation under stress before failure.
Cold Shut - Answers -A defect produced during casting, causing an area in the metal
where two portions of the metal in either a molten or plastic condition have come
together but have failed to unite, fuse, or blend into a solid mass.
Conductivity - Answers -The property of conducting heat or electric current.
Crack lamination - Answers -A defect appearing in sheets or strips as a segregation or
in layers.
Degradation - Answers -Damage caused over time to components and materials
caused by a range of physical processes, resulting in component failure.
Ductility - Answers -The ability of a material to deform easily upon the application of a
tensile force, or the ability of a material to withstand plastic deformation without rupture.
in other words, ductility is the ability of a material to undergo plastic deformation prior to
fracture.
Elasticity - Answers -In elastic strain, bonds are stretched but not broken. Therefore, the
material will return to its original shape when stresses are removed. The applied
stresses cause the atoms in a crystal to move from their equilibrium position. All the
atoms are displaced the same amount and still maintain their relative geometry. When
the stresses are removed, all the atoms return to their original positions and no
permanent deformation occurs.
Exothermic - Answers -Releases energy, i.e.: heat.
Hardenability - Answers -The hardenability of a metal alloy is its capability to be
hardened by heat treatment. It should not be confused with hardness, which is a
measure of the material's resistance to indentation or scratching. The hardenability of
ferrous alloys, namely steels, is a function of the carbon content and other alloying
elements, the grain size of the austenite, and the cooling rate.
, Hardness - Answers -The property of a material that enables it to resist plastic
deformation, penetration, indentation, and scratching.
Lattice - Answers -The Three-dimensional array of the atoms in a metal molecule, in
which the array is regular, repeating configuration in all directions.
Machinability - Answers -Machinability describes how a metal reacts to mechanical
deformation by removing chips, with respect to the amount of metal effectively removed
and the surface finish attainable. The mechanical properties of the metal will be the
factors that influence the machinability of a metal.
Malleability - Answers -The ability of a metal to exhibit large deformation of plastic
response when being subjected to compressive force.
pH - Answers -The measure of the acidity or alkalinity of a solution.
Plastic deformation - Answers -A dimensional change that does not disappear when the
initiating stress is removed. It is usually accompanied by some elastic strain. In plastic
deformation, bonds are broken which means the material will not return to its original
shape when stresses are removed.
Pores - Answers -Internal voids in a material.
Shrinkage cavity - Answers -A void left in cast metals as a result of solidification
shrinkage and the progressive freezing of metal towards the center.
Strain - Answers -Whenever a stress (no matter how small) is applied to a metal, a
proportional dimensional change or distortion must take place. Such a proportional
dimensional change (intensity or degree of the distortion) is called strain and is
measured as the total elongation per unit length of material due to some applied stress.
Strength - Answers -A measure of the ability of a material to support an applied load. It
is the ability of a material to resist deformation.
Stress - Answers --The internal resistance, or counterforce, of a material to the
distorting effects of an external force or load. These counterforces tend to return the
atoms to their normal positions. The total resistance developed is equal to the external
load. This resistance is known as stress.
-expressed in pounds per square inch.
Toughness - Answers -A combination of strength and ductility, i.e., the ability or capacity
of material to absorb energy and deform plastically before fracturing. Toughness
describes the way a material reacts under sudden impacts.
Water hammer - Answers -Water hammer (or, more generally, fluid hammer) is a
pressure surge or wave caused by the kinetic energy of a fluid in motion when it is
Certification Exam Questions and
Answers
Brittleness - Answers -The opposite of ductility. Brittle metals exhibit a small percentage
of elongation under stress before failure.
Cold Shut - Answers -A defect produced during casting, causing an area in the metal
where two portions of the metal in either a molten or plastic condition have come
together but have failed to unite, fuse, or blend into a solid mass.
Conductivity - Answers -The property of conducting heat or electric current.
Crack lamination - Answers -A defect appearing in sheets or strips as a segregation or
in layers.
Degradation - Answers -Damage caused over time to components and materials
caused by a range of physical processes, resulting in component failure.
Ductility - Answers -The ability of a material to deform easily upon the application of a
tensile force, or the ability of a material to withstand plastic deformation without rupture.
in other words, ductility is the ability of a material to undergo plastic deformation prior to
fracture.
Elasticity - Answers -In elastic strain, bonds are stretched but not broken. Therefore, the
material will return to its original shape when stresses are removed. The applied
stresses cause the atoms in a crystal to move from their equilibrium position. All the
atoms are displaced the same amount and still maintain their relative geometry. When
the stresses are removed, all the atoms return to their original positions and no
permanent deformation occurs.
Exothermic - Answers -Releases energy, i.e.: heat.
Hardenability - Answers -The hardenability of a metal alloy is its capability to be
hardened by heat treatment. It should not be confused with hardness, which is a
measure of the material's resistance to indentation or scratching. The hardenability of
ferrous alloys, namely steels, is a function of the carbon content and other alloying
elements, the grain size of the austenite, and the cooling rate.
, Hardness - Answers -The property of a material that enables it to resist plastic
deformation, penetration, indentation, and scratching.
Lattice - Answers -The Three-dimensional array of the atoms in a metal molecule, in
which the array is regular, repeating configuration in all directions.
Machinability - Answers -Machinability describes how a metal reacts to mechanical
deformation by removing chips, with respect to the amount of metal effectively removed
and the surface finish attainable. The mechanical properties of the metal will be the
factors that influence the machinability of a metal.
Malleability - Answers -The ability of a metal to exhibit large deformation of plastic
response when being subjected to compressive force.
pH - Answers -The measure of the acidity or alkalinity of a solution.
Plastic deformation - Answers -A dimensional change that does not disappear when the
initiating stress is removed. It is usually accompanied by some elastic strain. In plastic
deformation, bonds are broken which means the material will not return to its original
shape when stresses are removed.
Pores - Answers -Internal voids in a material.
Shrinkage cavity - Answers -A void left in cast metals as a result of solidification
shrinkage and the progressive freezing of metal towards the center.
Strain - Answers -Whenever a stress (no matter how small) is applied to a metal, a
proportional dimensional change or distortion must take place. Such a proportional
dimensional change (intensity or degree of the distortion) is called strain and is
measured as the total elongation per unit length of material due to some applied stress.
Strength - Answers -A measure of the ability of a material to support an applied load. It
is the ability of a material to resist deformation.
Stress - Answers --The internal resistance, or counterforce, of a material to the
distorting effects of an external force or load. These counterforces tend to return the
atoms to their normal positions. The total resistance developed is equal to the external
load. This resistance is known as stress.
-expressed in pounds per square inch.
Toughness - Answers -A combination of strength and ductility, i.e., the ability or capacity
of material to absorb energy and deform plastically before fracturing. Toughness
describes the way a material reacts under sudden impacts.
Water hammer - Answers -Water hammer (or, more generally, fluid hammer) is a
pressure surge or wave caused by the kinetic energy of a fluid in motion when it is
