MAE 364 Exam 1 Review Problems UPDATED
ACTUAL QUESTIONS AND CORRECT
ANSWERS
What is the 4-step procedure used to choose the best/most appropriate process for your
intended design? - CORRECT ANSWER 1. Select criteria (i.e. volume, required
material type, geometry, tolerances, values of product)
2. Identify processes (ex: quantity, material requirements, geometry needs)
3. Evaluate processes (process capability, processing time, tooling and equipment cost,
degree of automation available, skill required for operation, waste produced after processing,
post processing required)
4. Decision matrix/objective method for evaluation.
What is a unit process/operation? - CORRECT ANSWER Single step in a sequence of
steps required to transform the starting material into a final product.
What are two ways in which waste is produced through manufacturing? - CORRECT
ANSWER 1. Naturally as a result of the process
2. Defects
Casting - CORRECT ANSWER Taxonomy group: Phase change
Main steps:
1. Metal is heated until completely transformed to liquid.
2. Liquid is poured or directed into a mold cavity.
3. Liquid cools and solidifies in the mold (change in phase)
4. During solidification the metal assumes the shape of the mold cavity.
5. Casting removed from mold.
Factors to consider: pouring rate, solidification time, heat transfer, flow of metal, mold
material, etc.
Metal Forming - CORRECT ANSWER Taxonomy: Deformation processes
, Main steps:
1. A die applies stresses that exceed the yield strength of the material.
2. Material deforms and takes the shape determined by the die.
Important material properties:
1. Low yield strength
2. High ductility
Machining - CORRECT ANSWER Taxonomy: Mass change processes group
Main steps:
Remove or add material by mechanical, electrical, or chemical means.
Excess material is moved from the starting piece so what remains is the desired geometry.
Additive processes - CORRECT ANSWER Taxonomy: not part of any one processes
group, but can possibly be considered a part of many of the groups.
Main steps: (to create solid parts)
1. Liquid - cured into solid
2. Solid - laminated
3. Powder - aggregated and bonded.
What happens to the molten metal after pouring that comes into contact with the mold wall in
terms of grain structure and heat transfer direction? - CORRECT ANSWER Grain
structure: Cooler mold wall causes thin skin of solid metal to form.
Cooled through extraction of heat through mold wall.
Heat transfer direction: further grain formations occur in direction away from heat transfer.
How do metals solidify? (in terms of pure metal and alloy) - CORRECT
ANSWER Pure metal: Solidify at a constant temperature.
Alloy: Solidify over a range of temperatures
What do you see when you look at a phase diagram?
ACTUAL QUESTIONS AND CORRECT
ANSWERS
What is the 4-step procedure used to choose the best/most appropriate process for your
intended design? - CORRECT ANSWER 1. Select criteria (i.e. volume, required
material type, geometry, tolerances, values of product)
2. Identify processes (ex: quantity, material requirements, geometry needs)
3. Evaluate processes (process capability, processing time, tooling and equipment cost,
degree of automation available, skill required for operation, waste produced after processing,
post processing required)
4. Decision matrix/objective method for evaluation.
What is a unit process/operation? - CORRECT ANSWER Single step in a sequence of
steps required to transform the starting material into a final product.
What are two ways in which waste is produced through manufacturing? - CORRECT
ANSWER 1. Naturally as a result of the process
2. Defects
Casting - CORRECT ANSWER Taxonomy group: Phase change
Main steps:
1. Metal is heated until completely transformed to liquid.
2. Liquid is poured or directed into a mold cavity.
3. Liquid cools and solidifies in the mold (change in phase)
4. During solidification the metal assumes the shape of the mold cavity.
5. Casting removed from mold.
Factors to consider: pouring rate, solidification time, heat transfer, flow of metal, mold
material, etc.
Metal Forming - CORRECT ANSWER Taxonomy: Deformation processes
, Main steps:
1. A die applies stresses that exceed the yield strength of the material.
2. Material deforms and takes the shape determined by the die.
Important material properties:
1. Low yield strength
2. High ductility
Machining - CORRECT ANSWER Taxonomy: Mass change processes group
Main steps:
Remove or add material by mechanical, electrical, or chemical means.
Excess material is moved from the starting piece so what remains is the desired geometry.
Additive processes - CORRECT ANSWER Taxonomy: not part of any one processes
group, but can possibly be considered a part of many of the groups.
Main steps: (to create solid parts)
1. Liquid - cured into solid
2. Solid - laminated
3. Powder - aggregated and bonded.
What happens to the molten metal after pouring that comes into contact with the mold wall in
terms of grain structure and heat transfer direction? - CORRECT ANSWER Grain
structure: Cooler mold wall causes thin skin of solid metal to form.
Cooled through extraction of heat through mold wall.
Heat transfer direction: further grain formations occur in direction away from heat transfer.
How do metals solidify? (in terms of pure metal and alloy) - CORRECT
ANSWER Pure metal: Solidify at a constant temperature.
Alloy: Solidify over a range of temperatures
What do you see when you look at a phase diagram?
