MMET 281 EXAM QUESTIONS WITH
CORRECT ANSWERS | 100%
GUARANTEED PASS
What process is used to place coatings on tool handles? - Answer- Kip coating, powder
coating
Name a method that may be used to place a coating on fabric. - Answer- Knife or roller
coating, extrusion coating, calendaring
What causes the powder to atomize in fluidized-bed processing? - Answer- Air or inert
gas
Name four reasons for coating a substrate. - Answer- Color, chemical resistance,
cushioning, and electrical resistance
In electrostatic-bed coating, how is dry powder deposited on the part? - Answer- Electric
charge
Name three materials that vacuum-forming molds can be made from. - Answer- Plaster,
wood, fiberglass, metal, etc.
The sides of a thermoforming mold are tapered to aid in the removal of the part. This
taper is called _____. - Answer- Draft
Name four typical thermoformed products. - Answer- Ice cube trays, packaging,
drawers, instrument panels
The _____ of a female mold is the ratio of the maximum cavity depth to the minimum
span across the top opening. - Answer- Draw ratio
What is the major disadvantage of straight vacuum forming using deep cavities? -
Answer- Thinning
Name three advantages that metal thermoforming molds offer. - Answer- Durability,
Precision, thermal conductivity
Accurate, close-tolerance parts with food detail may be made by ______-______
forming. - Answer- Matched-mold
, Describe how product thickness is controlled in pressure-bubble plug-assisted vacuum
forming. - Answer- The to improved wall uniformity is stretching the sheet into an
approximately correct shape before contact with the mold. This will create uniform
stretching. Pressure bubble causes uniform stretch. Pug assist helps the sheet before it
is in the final shape.
Plastics with strength properties that increase by adding filler and reinforcing fibers to
the base resins are called ______. - Answer- Composites
The thin unreinforced layer of resin placed on the surface of a mold in the hand layup
process is called a _____. - Answer- Gel coat
The process of using reinforcements to improve selected properties of plastic parts is
called _____. - Answer- Reinforcing
In _____ molding, resin-soaked matting or roving are pulled through a long heated die. -
Answer- Pultrusion
Identify the type of adhesion created when materials are joined together and an
intermingling of molecules occurs. - Answer- Chemical adhesion
Name a bonding process similar to spot welding of metals. - Answer- Ultrasonic welding
or vibration welding
Name a bonding that is a method of fictionally joining circular thermoplastics together. -
Answer- Spin welding
Cements composed of solvents combined with a small quantity of the plastics to be
joined are called _____. - Answer- Dope cements
Name four basic ways plastics are joined. - Answer- Mechanical adhesion, chemical
adhesion, mechanical fastening, and friction fitting
Three types of intermolecular forces found in plastics are? - Answer- Van der Waal's,
dipole interactions, and hydrogen bonds
The term used to describe the tying of adjacent polymer chains is? - Answer-
Crosslinking
The hydrocarbon molecule that contains double bonds is called? - Answer- Unsaturated
If a material is transparent, is it crystalline? - Answer- Generally, transparent plastics are
amorphous
CORRECT ANSWERS | 100%
GUARANTEED PASS
What process is used to place coatings on tool handles? - Answer- Kip coating, powder
coating
Name a method that may be used to place a coating on fabric. - Answer- Knife or roller
coating, extrusion coating, calendaring
What causes the powder to atomize in fluidized-bed processing? - Answer- Air or inert
gas
Name four reasons for coating a substrate. - Answer- Color, chemical resistance,
cushioning, and electrical resistance
In electrostatic-bed coating, how is dry powder deposited on the part? - Answer- Electric
charge
Name three materials that vacuum-forming molds can be made from. - Answer- Plaster,
wood, fiberglass, metal, etc.
The sides of a thermoforming mold are tapered to aid in the removal of the part. This
taper is called _____. - Answer- Draft
Name four typical thermoformed products. - Answer- Ice cube trays, packaging,
drawers, instrument panels
The _____ of a female mold is the ratio of the maximum cavity depth to the minimum
span across the top opening. - Answer- Draw ratio
What is the major disadvantage of straight vacuum forming using deep cavities? -
Answer- Thinning
Name three advantages that metal thermoforming molds offer. - Answer- Durability,
Precision, thermal conductivity
Accurate, close-tolerance parts with food detail may be made by ______-______
forming. - Answer- Matched-mold
, Describe how product thickness is controlled in pressure-bubble plug-assisted vacuum
forming. - Answer- The to improved wall uniformity is stretching the sheet into an
approximately correct shape before contact with the mold. This will create uniform
stretching. Pressure bubble causes uniform stretch. Pug assist helps the sheet before it
is in the final shape.
Plastics with strength properties that increase by adding filler and reinforcing fibers to
the base resins are called ______. - Answer- Composites
The thin unreinforced layer of resin placed on the surface of a mold in the hand layup
process is called a _____. - Answer- Gel coat
The process of using reinforcements to improve selected properties of plastic parts is
called _____. - Answer- Reinforcing
In _____ molding, resin-soaked matting or roving are pulled through a long heated die. -
Answer- Pultrusion
Identify the type of adhesion created when materials are joined together and an
intermingling of molecules occurs. - Answer- Chemical adhesion
Name a bonding process similar to spot welding of metals. - Answer- Ultrasonic welding
or vibration welding
Name a bonding that is a method of fictionally joining circular thermoplastics together. -
Answer- Spin welding
Cements composed of solvents combined with a small quantity of the plastics to be
joined are called _____. - Answer- Dope cements
Name four basic ways plastics are joined. - Answer- Mechanical adhesion, chemical
adhesion, mechanical fastening, and friction fitting
Three types of intermolecular forces found in plastics are? - Answer- Van der Waal's,
dipole interactions, and hydrogen bonds
The term used to describe the tying of adjacent polymer chains is? - Answer-
Crosslinking
The hydrocarbon molecule that contains double bonds is called? - Answer- Unsaturated
If a material is transparent, is it crystalline? - Answer- Generally, transparent plastics are
amorphous
