EMAE 160 Exam Questions with
Complete Answers
Is forging always in the vertical direction? - ANSWER-No for example forging press
can be positioned horizontally
How is a soda can made? - ANSWER-deep drawing (not 100% sure)
What are the differences between deep drawing and impact extrusion? - ANSWER-
D = sheet-metal operation to make hollow-shaped parts from sheet blank
I = punch subjects metals to high pressures at room temperature, causing metal/slug
to be squeezed from die cavity forming the product.
Difference between impact and deep draw in material yield. - ANSWER-deep draw =
<80 % material yield
impact = >90 % material yield
Difference between impact and deep draw in wall/bottom thickness ratio. -
ANSWER-deep draw = 1:1 max
impacts = 1:2 min
Difference between impact and deep draw in length/width ratio. - ANSWER-deep
draw = 2:1
impact = 8:1 (Al) and 4:1 (steel)
How is high pressure tubing made? - ANSWER-seamless
How is low pressure tubing made? - ANSWER-welded
What is the most common metal used in extrusion? - ANSWER-Aluminum
How are the undercarriage tubes in the automotive industry created? - ANSWER-
Hydroforming
House gutters are manufactured using what process? - ANSWER-roll forming
What is metal spinning? - ANSWER-it is a disc or tube of metal spun at high speed
to form an axially symmetric part over a mandrel which can be done by CNC lathe or
by hand
What are the differences between metal spinning, shear spinning, and flow forming?
- ANSWER-in shear spinning a reduction of the wall thickness occurs.
What is the purpose of burnishing? - ANSWER-To compress surface, remove
starches, improve fatigue life
, What are the differences between fine blanking and standard sheet metal stamping?
- ANSWER-fine blanking = cutting sheet metal along a closed outline; the desired
product (blank) is the part cut out; (presses include hardened die punch and blanking
die, guide)
Standard sheet metal stamping = drives sharpened tool steel punch through sheet or
strip material into a die cavity. The finished part has predictable edge
How are most externally threaded fasteners manufactured? - ANSWER-machining,
cold forming/cold heading and manual die
What are the two systems used for measuring the hardness of heat-treated steels? -
ANSWER-burnell hardness no. and rockwell c scale
Explain the difference between liquid phase sintering and solid phase sintering when
describing the powdered metallurgy process - ANSWER-L = requires adding additive
to powder, which melts before matrix phase .
S = heat treatment of powder compacts at elevated temperatures.
Which process provides high material removal rate? - ANSWER-plasma arc cutting
What is the property that allows metals to be permanently deformed beyond yield
without failure by rupture or splitting? - ANSWER-Plasticity
Name 3 types of stress to which materials are subjected. - ANSWER-tensile,
compressive, shear
What is ultrasonic machining and can it be used for both metallic and nonmetallic
materials? - ANSWER-it is a vibrating, oscillating tool used to remove material from a
workpiece with the help of an abrasive slurry flowing freely between the workpiece
and tool. Can be used for every material.
(Advantages: little grinding pressure, good for brittle materials especially glass,
ceramics, semiconductors.)
Are applications of electron beam machining limited to metallic materials? Why or
why not? - ANSWER-Can only be used on metal bc electron melts metal. The
energy and power density can be controlled and high velocity electrons can be
concentrated to a narrow beam.
What type of indenter does a rockwell hardness testest ("C" scale) use to measure
the hardness of heat treated high-carbon steel? - ANSWER-120 degree diamond
cone
In terms of the powdered metallurgy process, what is impregnation? - ANSWER-
filling a porous substrate to make it airtight. In powder metallurgy, impregnate inner
void prior to plating to reduce corrosion. Fill sintered component with lubricants
Complete Answers
Is forging always in the vertical direction? - ANSWER-No for example forging press
can be positioned horizontally
How is a soda can made? - ANSWER-deep drawing (not 100% sure)
What are the differences between deep drawing and impact extrusion? - ANSWER-
D = sheet-metal operation to make hollow-shaped parts from sheet blank
I = punch subjects metals to high pressures at room temperature, causing metal/slug
to be squeezed from die cavity forming the product.
Difference between impact and deep draw in material yield. - ANSWER-deep draw =
<80 % material yield
impact = >90 % material yield
Difference between impact and deep draw in wall/bottom thickness ratio. -
ANSWER-deep draw = 1:1 max
impacts = 1:2 min
Difference between impact and deep draw in length/width ratio. - ANSWER-deep
draw = 2:1
impact = 8:1 (Al) and 4:1 (steel)
How is high pressure tubing made? - ANSWER-seamless
How is low pressure tubing made? - ANSWER-welded
What is the most common metal used in extrusion? - ANSWER-Aluminum
How are the undercarriage tubes in the automotive industry created? - ANSWER-
Hydroforming
House gutters are manufactured using what process? - ANSWER-roll forming
What is metal spinning? - ANSWER-it is a disc or tube of metal spun at high speed
to form an axially symmetric part over a mandrel which can be done by CNC lathe or
by hand
What are the differences between metal spinning, shear spinning, and flow forming?
- ANSWER-in shear spinning a reduction of the wall thickness occurs.
What is the purpose of burnishing? - ANSWER-To compress surface, remove
starches, improve fatigue life
, What are the differences between fine blanking and standard sheet metal stamping?
- ANSWER-fine blanking = cutting sheet metal along a closed outline; the desired
product (blank) is the part cut out; (presses include hardened die punch and blanking
die, guide)
Standard sheet metal stamping = drives sharpened tool steel punch through sheet or
strip material into a die cavity. The finished part has predictable edge
How are most externally threaded fasteners manufactured? - ANSWER-machining,
cold forming/cold heading and manual die
What are the two systems used for measuring the hardness of heat-treated steels? -
ANSWER-burnell hardness no. and rockwell c scale
Explain the difference between liquid phase sintering and solid phase sintering when
describing the powdered metallurgy process - ANSWER-L = requires adding additive
to powder, which melts before matrix phase .
S = heat treatment of powder compacts at elevated temperatures.
Which process provides high material removal rate? - ANSWER-plasma arc cutting
What is the property that allows metals to be permanently deformed beyond yield
without failure by rupture or splitting? - ANSWER-Plasticity
Name 3 types of stress to which materials are subjected. - ANSWER-tensile,
compressive, shear
What is ultrasonic machining and can it be used for both metallic and nonmetallic
materials? - ANSWER-it is a vibrating, oscillating tool used to remove material from a
workpiece with the help of an abrasive slurry flowing freely between the workpiece
and tool. Can be used for every material.
(Advantages: little grinding pressure, good for brittle materials especially glass,
ceramics, semiconductors.)
Are applications of electron beam machining limited to metallic materials? Why or
why not? - ANSWER-Can only be used on metal bc electron melts metal. The
energy and power density can be controlled and high velocity electrons can be
concentrated to a narrow beam.
What type of indenter does a rockwell hardness testest ("C" scale) use to measure
the hardness of heat treated high-carbon steel? - ANSWER-120 degree diamond
cone
In terms of the powdered metallurgy process, what is impregnation? - ANSWER-
filling a porous substrate to make it airtight. In powder metallurgy, impregnate inner
void prior to plating to reduce corrosion. Fill sintered component with lubricants
