Chapter 3 Final

Question 1

What are the four major steps in composite product fabrication?

Answer 1

Forming, Machining, Joining & Assembly, and Finishing.

Question 2

What is the purpose of the forming step in composite fabrication?

Answer 2

To shape the raw composite materials into the desired shape and size using heat and pressure.

Question 3

What are the common machining techniques used in composite processing?

Answer 3

Drilling, turning, cutting, and grinding.

Question 4

What are some joining and assembly methods for composites?

Answer 4

Adhesive bonding, fusion bonding, and mechanical fastening.

Question 5

Why is joining and assembly often avoided in composite manufacturing?

Answer 5

To maintain structural integrity and avoid weak points in the material.

Question 6

What is the purpose of finishing in composite fabrication?

Answer 6

To improve appearance, protect against environmental degradation, and enhance wear resistance.

Question 7

What are the two main categories of composites processing?

Answer 7

Thermoset processing and thermoplastic processing.

Question 8

What are the main thermoset composite processing techniques for short fiber composites?

Answer 8

Sheet Molding Compound (SMC), Bulk Molding Compound (BMC), Spray-up, and Injection Molding.

Question 9

What are the main thermoset composite processing techniques for continuous fiber composites?

Answer 9

Filament Winding, Pultrusion, Resin Transfer Molding (RTM), and Hand Lay-up.

Question 10

What are the main thermoplastic composite processing techniques for short fiber composites?

Answer 10

Injection Molding and Blow Molding.

Question 11

What are the main thermoplastic composite processing techniques for continuous fiber composites?

Answer 11

Compression Molding, Thermoforming, and Tape Winding.

Question 12

Why are composites widely used in the aerospace industry?

Answer 12

They provide high performance, weight reduction, and dimensional stability.

Question 13

What type of composite is commonly used in automotive applications?

Answer 13

Glass fiber-reinforced composites.

Question 14

Why are composites used in the marine industry?

Answer 14

They offer lightweight properties and high corrosion resistance.

Question 15

Why are composites used in construction and civil structures?

Answer 15

They reduce installation and maintenance costs while improving durability and corrosion resistance

Question 16

Why are thermoset resins used in composites?

Answer 16

They have high thermal stability, good fiber impregnation, and cannot be remelted.

Question 17

What are common thermoset resins used in composites?

Answer 17

Epoxy, Polyester, and Phenolics

Question 18

What is the main advantage and disadvantages of epoxy resin in composites?

Answer 18

• It has excellent adhesion, low shrinkage, and high chemical resistance.
• But It is generally brittle and more expensive than polyester resin.

Question 19

Why is polyester resin commonly used in composites?

Answer 19

It is low-cost and has excellent corrosion resistance.

Question 20

What are common thermoplastic resins used in composites?

Answer 20

Nylon, Polypropylene (PP), Polyethylene (PE), and Polystyrene.

Question 21

What is the main advantage and disadvantages of thermoplastic resins in composites?

Answer 21

• They can be reshaped and recycled.
• But They require high processing temperatures and pressures.

Question 22

What are the three main types of reinforcement fibers?

Answer 22

Glass fiber, Carbon fiber, and Aramid fiber.

Question 23

What are the key raw materials used to produce glass fiber?

Answer 23

Silica, alumina, limestone, and boric acid.

Question 24

What are the main steps in glass fiber production?

Answer 24

Batching, Melting, Fiberization, Coating/Sizing, and Drying/Packaging.

Question 25

What is the purpose of sizing in glass fiber production?

Answer 25

It promotes fiber wetting, enhances fiber-resin bonding, and prevents fiber breakage.

Question 26

What are the three main types of carbon fiber precursors?

Answer 26

PAN-based, Pitch-based, and Rayon-based.

Question 27

What are the main steps in carbon fiber production?

Answer 27

Oxidation, Carbonization, Surface Treatment, and Sizing.

Question 28

What is the main advantage and disadvantage of carbon fiber in composites?

Answer 28

• It has high strength-to-weight ratio and excellent stiffness.
• But It is expensive and brittle.

Question 29

What is Kevlar® used for? And disadvantage

Answer 29

• Bulletproof vests, puncture-resistant tires, and fire-resistant clothing.
• But It is difficult to cut and machine.

Question 30

What are the different forms of fiber reinforcement?

Answer 30

Continuous fibers, Discontinuous fibers, Woven fabrics, and Multidirectional fabrics.

Question 31

What is the main advantage of woven fabric reinforcement?

Answer 31

It provides strength in multiple directions.

Question 32

What is a nonwoven fabric in composites?

Answer 32

A fabric where fibers are laid parallel and stitched together with polyester thread.

Question 33

What are the two main types of molding compounds?

Answer 33

Sheet Molding Compound (SMC)
- A ready-to-mold composite sheet containing uncured thermoset resins, fibers, and fillers.
and Bulk Molding Compound (BMC)
- A composite material in dough or log form containing short fibers and resin.

Question 34

What are the main advantages of BMC?

Answer 34

It allows complex part shapes and has a fast processing time.