©THEBRIGHT EXAM SOLUTIONS
10/30/2024 11:32 PM
Power Engineering - 2A2 (Chapter 5) Exam
Questions And Answers 100% Pass
What are the two main categories of material testing? - answer✔Destructive testing
Non-destructive testing / Non-destructive examination (NDE)
What are the four methods of destructive testing? - answer✔Tensile Tests
Hardness Tests
Impact Tests
Proof Tests
In a tensile test, how is the shape of the specimen determined? - answer✔The shape is defined
by the standards established by ASTM
In a tensile test, why is the shape of the specimen important? - answer✔So that the beak
occurs in the "gauge length" section.
What is the mechanism called that is used for performing tensile tests? - answer✔An
extensometer
When performing tensile tests, what are the five stress points plotted? - answer✔Proportional
Limit
Yield stress
Proof Stress
Ultimate tensile Strength
Final instability point
, ©THEBRIGHT EXAM SOLUTIONS
10/30/2024 11:32 PM
What is the proportional limit as it pertains to tensile tests? - answer✔The stress point at which
slip (or glide) due to dislocation movement occurs.
What is yield stress as it pertains to tensile tests? - answer✔The stress at which yielding occurs
across the whole specimen.
At this point, deformation is purely plastic (non-reversible)
What is proof stress as it pertains to tensile tests? - answer✔The point at which a specimen has
undergone a certain value of permanent strain. Usually 0.2%
What is the ultimate tensile strength (UTS) as it pertains to tensile tests? - answer✔It is the
point at which plastic deformation becomes unstable and a narrow region (a neck) forms in the
specimen.
What is the final instability point as it pertains to tensile tests? - answer✔It is the failure point,
at which fracture occurs.
What are the two main types of strain? - answer✔Elastic strain
Plastic strain
Explain elastic strain - answer✔Elastic strain is the stretching of material within its elastic limit.
It will return to its original dimensions when the stress is removed.
Explain plastic strain - answer✔Plastic strain happens once the material has exceeded its elastic
limit. It is the irreversible deformation of a material.
What is engineering strain? - answer✔This is the one outlined in the academic supplement.
Strain=ΔL/Original L
What is true strain? - answer✔It is similar to engineering strain but based on the instantaneous
length of the specimen as the test progresses.
Instantaneous length
True Strain = ln --------------------------
, ©THEBRIGHT EXAM SOLUTIONS
10/30/2024 11:32 PM
Original length
What is the hardness measurement? - answer✔The resistance of a material to surface
indentation.
What are the four common hardness testing methods? - answer✔Brinell
Rockwell
Vickers
Knoop
Describe the Brinell Hardness Test. - answer✔Specimen placed on an anvil
Load applied through a plunger and ball
Held for 10 to 30 seconds
Diameter measured twice offset by 90° to get mean diameter
Hardness number calculated
What is the most widely used hardness test? Why? - answer✔The Rockwell hardness test
Because it's simple to perform
What do Rockwell hardness testers use as an indentor? - answer✔Either a diamond cone or ball
What are the letters that follow the numerical value for a Rockwell hardness test? What do
they mean? - answer✔1234 H R (B or C)
H = Hardness
R = Rockwell
B or C = Ball or Cone
Describe a Rockwell Hardness test. - answer✔A ball or diamond cone is pressed into a specimen
at two loads (light load and heavy load.) The difference in depth is given a numerical value as
indicated on a dial depth gauge.
What do Vickers Hardness testers use as an indentor? - answer✔Diamond pyramid
10/30/2024 11:32 PM
Power Engineering - 2A2 (Chapter 5) Exam
Questions And Answers 100% Pass
What are the two main categories of material testing? - answer✔Destructive testing
Non-destructive testing / Non-destructive examination (NDE)
What are the four methods of destructive testing? - answer✔Tensile Tests
Hardness Tests
Impact Tests
Proof Tests
In a tensile test, how is the shape of the specimen determined? - answer✔The shape is defined
by the standards established by ASTM
In a tensile test, why is the shape of the specimen important? - answer✔So that the beak
occurs in the "gauge length" section.
What is the mechanism called that is used for performing tensile tests? - answer✔An
extensometer
When performing tensile tests, what are the five stress points plotted? - answer✔Proportional
Limit
Yield stress
Proof Stress
Ultimate tensile Strength
Final instability point
, ©THEBRIGHT EXAM SOLUTIONS
10/30/2024 11:32 PM
What is the proportional limit as it pertains to tensile tests? - answer✔The stress point at which
slip (or glide) due to dislocation movement occurs.
What is yield stress as it pertains to tensile tests? - answer✔The stress at which yielding occurs
across the whole specimen.
At this point, deformation is purely plastic (non-reversible)
What is proof stress as it pertains to tensile tests? - answer✔The point at which a specimen has
undergone a certain value of permanent strain. Usually 0.2%
What is the ultimate tensile strength (UTS) as it pertains to tensile tests? - answer✔It is the
point at which plastic deformation becomes unstable and a narrow region (a neck) forms in the
specimen.
What is the final instability point as it pertains to tensile tests? - answer✔It is the failure point,
at which fracture occurs.
What are the two main types of strain? - answer✔Elastic strain
Plastic strain
Explain elastic strain - answer✔Elastic strain is the stretching of material within its elastic limit.
It will return to its original dimensions when the stress is removed.
Explain plastic strain - answer✔Plastic strain happens once the material has exceeded its elastic
limit. It is the irreversible deformation of a material.
What is engineering strain? - answer✔This is the one outlined in the academic supplement.
Strain=ΔL/Original L
What is true strain? - answer✔It is similar to engineering strain but based on the instantaneous
length of the specimen as the test progresses.
Instantaneous length
True Strain = ln --------------------------
, ©THEBRIGHT EXAM SOLUTIONS
10/30/2024 11:32 PM
Original length
What is the hardness measurement? - answer✔The resistance of a material to surface
indentation.
What are the four common hardness testing methods? - answer✔Brinell
Rockwell
Vickers
Knoop
Describe the Brinell Hardness Test. - answer✔Specimen placed on an anvil
Load applied through a plunger and ball
Held for 10 to 30 seconds
Diameter measured twice offset by 90° to get mean diameter
Hardness number calculated
What is the most widely used hardness test? Why? - answer✔The Rockwell hardness test
Because it's simple to perform
What do Rockwell hardness testers use as an indentor? - answer✔Either a diamond cone or ball
What are the letters that follow the numerical value for a Rockwell hardness test? What do
they mean? - answer✔1234 H R (B or C)
H = Hardness
R = Rockwell
B or C = Ball or Cone
Describe a Rockwell Hardness test. - answer✔A ball or diamond cone is pressed into a specimen
at two loads (light load and heavy load.) The difference in depth is given a numerical value as
indicated on a dial depth gauge.
What do Vickers Hardness testers use as an indentor? - answer✔Diamond pyramid
