Chapter 3 Final Flashcards
What are the four major steps in composite product fabrication?
Forming, Machining, Joining & Assembly, and Finishing.
What is the purpose of the forming step in composite fabrication?
To shape the raw composite materials into the desired shape and size using heat and pressure.
What are the common machining techniques used in composite processing?
Drilling, turning, cutting, and grinding.
What are some joining and assembly methods for composites?
Adhesive bonding, fusion bonding, and mechanical fastening.
Why is joining and assembly often avoided in composite manufacturing?
To maintain structural integrity and avoid weak points in the material.
What is the purpose of finishing in composite fabrication?
To improve appearance, protect against environmental degradation, and enhance wear resistance.
What are the two main categories of composites processing?
Thermoset processing and thermoplastic processing.
What are the main thermoset composite processing techniques for short fiber composites?
Sheet Molding Compound (SMC), Bulk Molding Compound (BMC), Spray-up, and Injection Molding.
What are the main thermoset composite processing techniques for continuous fiber composites?
Filament Winding, Pultrusion, Resin Transfer Molding (RTM), and Hand Lay-up.
What are the main thermoplastic composite processing techniques for short fiber composites?
Injection Molding and Blow Molding.
What are the main thermoplastic composite processing techniques for continuous fiber composites?
Compression Molding, Thermoforming, and Tape Winding.
Why are composites widely used in the aerospace industry?
They provide high performance, weight reduction, and dimensional stability.
What type of composite is commonly used in automotive applications?
Glass fiber-reinforced composites.
Why are composites used in the marine industry?
They offer lightweight properties and high corrosion resistance.
Why are composites used in construction and civil structures?
They reduce installation and maintenance costs while improving durability and corrosion resistance
Why are thermoset resins used in composites?
They have high thermal stability, good fiber impregnation, and cannot be remelted.
What are common thermoset resins used in composites?
Epoxy, Polyester, and Phenolics
What is the main advantage and disadvantages of epoxy resin in composites?
- It has excellent adhesion, low shrinkage, and high chemical resistance.
- But It is generally brittle and more expensive than polyester resin.
Why is polyester resin commonly used in composites?
It is low-cost and has excellent corrosion resistance.
What are common thermoplastic resins used in composites?
Nylon, Polypropylene (PP), Polyethylene (PE), and Polystyrene.
What is the main advantage and disadvantages of thermoplastic resins in composites?
- They can be reshaped and recycled.
- But They require high processing temperatures and pressures.
What are the three main types of reinforcement fibers?
Glass fiber, Carbon fiber, and Aramid fiber.
What are the key raw materials used to produce glass fiber?
Silica, alumina, limestone, and boric acid.
What are the main steps in glass fiber production?
Batching, Melting, Fiberization, Coating/Sizing, and Drying/Packaging.
What is the purpose of sizing in glass fiber production?
It promotes fiber wetting, enhances fiber-resin bonding, and prevents fiber breakage.
What are the three main types of carbon fiber precursors?
PAN-based, Pitch-based, and Rayon-based.
What are the main steps in carbon fiber production?
Oxidation, Carbonization, Surface Treatment, and Sizing.
What is the main advantage and disadvantage of carbon fiber in composites?
- It has high strength-to-weight ratio and excellent stiffness.
- But It is expensive and brittle.
What is Kevlar® used for? And disadvantage
- Bulletproof vests, puncture-resistant tires, and fire-resistant clothing.
- But It is difficult to cut and machine.
What are the different forms of fiber reinforcement?
Continuous fibers, Discontinuous fibers, Woven fabrics, and Multidirectional fabrics.
What is the main advantage of woven fabric reinforcement?
It provides strength in multiple directions.
What is a nonwoven fabric in composites?
A fabric where fibers are laid parallel and stitched together with polyester thread.
What are the two main types of molding compounds?
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.
What are the main advantages of BMC?
It allows complex part shapes and has a fast processing time.
