Podcast
Questions and Answers
What is the primary purpose of a prepreg in composite manufacturing?
What is the primary purpose of a prepreg in composite manufacturing?
Which of the following materials is NOT typically used for low-cost composite applications?
Which of the following materials is NOT typically used for low-cost composite applications?
What behavior is exhibited by a fiber bed during the manufacturing process?
What behavior is exhibited by a fiber bed during the manufacturing process?
Which step is involved in the Dry lay-up process?
Which step is involved in the Dry lay-up process?
Signup and view all the answers
In composite manufacturing, what role does the vacuum bag play?
In composite manufacturing, what role does the vacuum bag play?
Signup and view all the answers
What is the primary reason there are more thermoset matrix composites compared to thermoplastic matrix composites?
What is the primary reason there are more thermoset matrix composites compared to thermoplastic matrix composites?
Signup and view all the answers
Which of the following is a thermoplastic matrix composite?
Which of the following is a thermoplastic matrix composite?
Signup and view all the answers
What is the molecular weight of maleic acid used in the polyester production example?
What is the molecular weight of maleic acid used in the polyester production example?
Signup and view all the answers
What is the mass of water produced when 100 g of maleic acid reacts with ethylene glycol?
What is the mass of water produced when 100 g of maleic acid reacts with ethylene glycol?
Signup and view all the answers
What is the stoichiometric amount of ethylene glycol required to react with 100 g of maleic acid?
What is the stoichiometric amount of ethylene glycol required to react with 100 g of maleic acid?
Signup and view all the answers
Which peroxide is represented by the chemical structure H-OO-H?
Which peroxide is represented by the chemical structure H-OO-H?
Signup and view all the answers
In the context of cross linking polyester, how many styrene monomers correspond to one oligoester?
In the context of cross linking polyester, how many styrene monomers correspond to one oligoester?
Signup and view all the answers
What is the total mass of polyester obtained when using 100 g of maleic acid?
What is the total mass of polyester obtained when using 100 g of maleic acid?
Signup and view all the answers
What is the primary method used to mix the epoxy/clay samples in the provided data?
What is the primary method used to mix the epoxy/clay samples in the provided data?
Signup and view all the answers
Which measurement indicates the improvement in fracture toughness of composite samples?
Which measurement indicates the improvement in fracture toughness of composite samples?
Signup and view all the answers
What are the regions labeled in the graph for crack growth in the normalized stiffness plot?
What are the regions labeled in the graph for crack growth in the normalized stiffness plot?
Signup and view all the answers
Which parameter is represented along the x-axis of the fatigue life graph?
Which parameter is represented along the x-axis of the fatigue life graph?
Signup and view all the answers
What is the outcome of the epoxy/clay mixing method described?
What is the outcome of the epoxy/clay mixing method described?
Signup and view all the answers
Which sample was measured at 8.24 nm in the X-ray diffraction pattern?
Which sample was measured at 8.24 nm in the X-ray diffraction pattern?
Signup and view all the answers
Which step is NOT part of the procedure to incorporate modified epoxy into long continuous carbon fibers?
Which step is NOT part of the procedure to incorporate modified epoxy into long continuous carbon fibers?
Signup and view all the answers
What does the Y-axis of the first graph primarily represent?
What does the Y-axis of the first graph primarily represent?
Signup and view all the answers
What effect does high speed mixing have on the samples according to the provided data?
What effect does high speed mixing have on the samples according to the provided data?
Signup and view all the answers
What is indicated by the measurement 4phr in the G_Ic, J/m² graph?
What is indicated by the measurement 4phr in the G_Ic, J/m² graph?
Signup and view all the answers
How does higher cross link density affect heat distortion temperature?
How does higher cross link density affect heat distortion temperature?
Signup and view all the answers
Which method is used to measure the degree of cure at the solid stage?
Which method is used to measure the degree of cure at the solid stage?
Signup and view all the answers
What is a key characteristic of vinyl ester resin?
What is a key characteristic of vinyl ester resin?
Signup and view all the answers
What does the rate of cure depend on according to the formula provided?
What does the rate of cure depend on according to the formula provided?
Signup and view all the answers
Which resin is stable at the highest temperature?
Which resin is stable at the highest temperature?
Signup and view all the answers
What principle does the acetone wipe serve in quality control?
What principle does the acetone wipe serve in quality control?
Signup and view all the answers
What is one of the primary uses of the phenolic matrix?
What is one of the primary uses of the phenolic matrix?
Signup and view all the answers
Which material is known for having high shrinkage and brittleness?
Which material is known for having high shrinkage and brittleness?
Signup and view all the answers
What is the effect of adding fillers to phenolic materials?
What is the effect of adding fillers to phenolic materials?
Signup and view all the answers
Which test is NOT associated with measuring the degree of cure?
Which test is NOT associated with measuring the degree of cure?
Signup and view all the answers
What is the primary distinction between braided structures and mats in fiber forms?
What is the primary distinction between braided structures and mats in fiber forms?
Signup and view all the answers
Which type of weave would typically provide the strongest fabric structure?
Which type of weave would typically provide the strongest fabric structure?
Signup and view all the answers
In the equation for deformation of a fiber bundle, what does the term $Va$ represent?
In the equation for deformation of a fiber bundle, what does the term $Va$ represent?
Signup and view all the answers
Which of the following statements about fiber volume parameters is true?
Which of the following statements about fiber volume parameters is true?
Signup and view all the answers
What is the primary purpose of winding in fiber processing?
What is the primary purpose of winding in fiber processing?
Signup and view all the answers
In the deformation equations for curved beams under bending load, which variable represents the load applied perpendicular to the beam?
In the deformation equations for curved beams under bending load, which variable represents the load applied perpendicular to the beam?
Signup and view all the answers
Which of the following could be a result of fiber bundles being subjected to axial loads?
Which of the following could be a result of fiber bundles being subjected to axial loads?
Signup and view all the answers
What does the variable $σ_b$ represent in fiber mechanics?
What does the variable $σ_b$ represent in fiber mechanics?
Signup and view all the answers
Which of the following methods is NOT typically used in fiber processing?
Which of the following methods is NOT typically used in fiber processing?
Signup and view all the answers
How is the volume fraction of fibers calculated in a fiber bundle?
How is the volume fraction of fibers calculated in a fiber bundle?
Signup and view all the answers
Which type of fiber yields the best tensile strength when twisted into fibers?
Which type of fiber yields the best tensile strength when twisted into fibers?
Signup and view all the answers
In the mechanics of a fiber bundle, what does the expression $∆x = \frac{P_x}{EA}$ calculate?
In the mechanics of a fiber bundle, what does the expression $∆x = \frac{P_x}{EA}$ calculate?
Signup and view all the answers
Which factor does NOT influence the deformation of a fiber under load?
Which factor does NOT influence the deformation of a fiber under load?
Signup and view all the answers
To enhance the mechanical properties of a fiber bundle, which of the following would be a beneficial processing technique?
To enhance the mechanical properties of a fiber bundle, which of the following would be a beneficial processing technique?
Signup and view all the answers
In the given equation, what does $T$ represent?
In the given equation, what does $T$ represent?
Signup and view all the answers
What does the variable $m$ signify in the exponential function $e^{-mt}$?
What does the variable $m$ signify in the exponential function $e^{-mt}$?
Signup and view all the answers
Which of the following correctly expresses the relationship between $Q_c$ and $T$?
Which of the following correctly expresses the relationship between $Q_c$ and $T$?
Signup and view all the answers
What is the value of $To$ in this scenario?
What is the value of $To$ in this scenario?
Signup and view all the answers
During the first increment, what is the change in temperature from the start to the end?
During the first increment, what is the change in temperature from the start to the end?
Signup and view all the answers
What does $K_1$ represent in the context provided?
What does $K_1$ represent in the context provided?
Signup and view all the answers
What mathematical operation is represented by $d\alpha/dt$?
What mathematical operation is represented by $d\alpha/dt$?
Signup and view all the answers
In the equation for $Qc$, what does the factor $(1 - \alpha)^{2.1}$ imply?
In the equation for $Qc$, what does the factor $(1 - \alpha)^{2.1}$ imply?
Signup and view all the answers
Which of the following best describes the term $K_2$?
Which of the following best describes the term $K_2$?
Signup and view all the answers
What does the term $d\alpha$ in the incremental solution represent?
What does the term $d\alpha$ in the incremental solution represent?
Signup and view all the answers
Study Notes
Manufacturing of Composites - MECH 415/6521
- Course is taught by Suong V. Hoa
- Course is offered by Concordia Center for Composites, Mechanical and Industrial Engineering, Concordia University
- Focuses on the introduction to the manufacturing of composites
General Characteristics of Manufacturing Composites
-
Requirements for a good composite piece:
- Good bonding between matrix and fibers
- Proper orientation of fibers
- Sufficient volume fraction of fibers
- Uniform distribution of fibers within the matrix
- Proper curing or solidification of the resin
- Limited voids and defects
- Good dimensional control of the final part
-
Good bonding = better strength and stiffness
-
Poor bonding = stress concentration, dry spots
-
Partial bonding can help absorb impact energy
Fiber Orientation
- Fibers tend to be wavy (microwaviness)
- Overlapping
- Misalignment due to liquid flow during manufacturing
- Reinforcement along thickness direction (pinning, 3D weaving)
- Hard pressing with stiff rollers
- Molding over complex geometries
- Human errors during Hand Lay Up
Fiber Volume Fraction
- Vf = Vf / Vc (Vf = volume fraction of fibers, Vc = volume fraction of composite)
- E = EfVf + EmVm (E = composite modulus, Ef = fiber modulus, Em = matrix modulus)
- 1 = Vf + Vm + Vv (1 = total volume, Vf = volume fraction of fibers, Vm = volume fraction of matrix, V v = volume fraction of voids)
Uniform Fiber Distribution
- Resin rich area
- Fiber to fiber contact
Proper Curing of the Resin
- Curing for thermosets
- Consolidation for thermoplastics
Limited Amounts of Voids and Defects
- Less than 1% voids
Good Dimensional Control of the Part
- Images of parts with good and poor dimensional control
Metal versus Composites Manufacturing
- Different manufacturing methods for metals (compared to composites)
- Composite manufacturing process breakdown (schematics)
Functions of Constituents
- Fibers
- Matrix
- Interface
Advantages of Fiber Form
- Stronger than bulk form
- More fabrication techniques
- Flexibility in forming
- Stretching, drawing, solvent removal
Disadvantages of Fiber Form
- Requirements of large number of fibers
- Need to be bonded together to provide good mechanical properties
- Need for high fiber volume fraction
- Small inter-fiber spacing (leading to stress concentration)
Matrix Materials
- Functions of the matrix:
- Aligning the fibers
- Transferring load between fibers
- Assisting fibers in providing compression strength and modulus
- Assisting fibers in providing shear strength and modulus
- Protecting fibers from environmental attack
Interface
- Two main requirements for good interface:
- Compatibility (depends on surface energy)
- Availability (depends on speed to be on site)
Volume Fraction and Weight Fraction
- Vf = Vf / Vc
- Wf = Wf / Wc
- Percent (%) and Parts per hundred (phr)
How are Composite Structures Made?
- Diagrams illustrating the composite manufacturing process breakdown (schematic)
Different types of Matrix Materials
- Polymer matrix composites
- Carbon/epoxy
- Glass/epoxy
- Glass/polyester
- Kevlar/epoxy
- Metal matrix composites
- Silicon carbide/aluminum
- Carbon fiber/aluminum
- Ceramic matrix composites
- Carbon/carbon
- Carbon/alumina
- More polymer matrix composites than other types (due to compatibility)
Different types of Polymer Matrix Materials
- Thermoset matrix composites
- Carbon/epoxy
- Glass/epoxy
- Glass/polyester
- Kevlar/epoxy
- Thermoplastic matrix composites
- Carbon/PEEK
- Carbon/PPS
- Glass/nylon
- More thermoset matrix composites than thermoplastic matrix (due to availability)
Viscosity of Thermoset and Thermoplastic Materials
- Table of materials, viscosities, temperature
- Units: Centipoise, Pa-sec
Schematic of thermoset resin molecules
- Images of various stages of thermoset resin molecule formations
Polyester Production
- Chemical reactions and formulas for polyester production
Example on Cross Linking of Polyester
- Calculations and formulas for determining the mass of polyester obtained from different reactants
Initiators
- Table of names and chemical structures of commercial organic peroxides
Polyester Cross Linking
- Diagram illustrating the chemical reactions involved in polyester cross-linking
Atomic Bond Energy
- Table of different atomic bonds and their energies (in kJ/mole)
Example on Heat Generation and Temperature Increase
- Calculations related to heat generation and temperature increase during polymerization process for different materials
Different Types of Reactants
- Chemical structures and formulas for different reactants (e.g., ethylene glycol, orthophthalic acid, maleic acid)
Polyester use and Storage
- Container for shipping and storage, Shelf life, Pot life, Inhibitors, Accelerators, Prepregs, Coupling agents, Fillers
Epoxy
- Commonly used resin for advanced composites
- Good adhesive strength
- Low shrinkage
- Operating temperature up to 140 °C
Diglycidyl ether of bisphenol A (DGEBPA)
- Chemical structure of this epoxy-based product
Formation of epoxy resin
- Chemical reactions with diagrams for creating various epoxy systems
Specialty Epoxy Resins
- Diglycidyl ether of bisphenol A (DGEBPA)
- Epoxy Novolac (Epoxidized Phenolic Resin) – DOW DEN 438
- Tetraglycidyl ether of Tetrakis (Hydroxyphenyl) Ether – SHELL EPON 103
Diluents
- Reduce resin viscosity
- Improve shelf/pot life
- Lower exotherm
- React with resin, become part of cured system
- Butyl glycidyl ether, Cresyl glycidyl ether, Phenyl glycidyl ether
Curing Systems for Epoxies
- Amines
- Anhydrides
- Tertiary amines and accelerators
Amine Curing Agents
- Table listing amine curing agents, hydrogen equivalent weights, and viscosities at 25°C
Amine curing agents
- Chemical reactions with diagrams for amine curing systems
Stoichiometric Ratio
- Calculations and formulas to determine the appropriate ratio of amine to epoxy for curing
Anhydride Curing Agent
- Chemical structure and reaction for phthalic anhydride (PA) curing systems
Tertiary Amines and Accelerators
- Reactions and diagrams for tertiary amine curing systems
- EMI accelerator
Relative Concentration
- Large excess of epoxy
- One reactive epoxy site for one reactive hardener site
- One epoxy molecule for one hardener molecule
- High excess of hardener
Cured Epoxy Resin Systems
- Aromatic rings
- Cross-link density
- Lower cross-link density improves toughness, lower shrinkage
- Higher cross-link density improves chemical resistance, higher heat distortion temperature
Pot Life
- Prepregs- Shelf life
Quality Control
- At the liquid stage: Measure viscosity
- At the solid stage: Degree of cure
- Chemical principle: FTIR, Acetone wipe
- Electrical principle
- Mechanical principle: Barcol hardness test, DMA, Ultrasonic, Shrinkage measurement
- Thermal principle: DSC test
Degree of cure and rate of cure
- Equation
Vinyl Ester Resin
- Chemical structures of different vinyl ester resins
Vinyl ester resin formation
- Chemical reactions for vinyl ester resin formation, with additional reactants and catalysts
Polyimide
- High temperature stability (up to 350°C)
- Epoxies stable up to 177°C
### Bismalimide (BMI)
- Cured at 177°C
- Post-cured at 246°C for complete cure.
- Properties significantly higher than epoxies
Phenolic Matrix
- High-temperature applications
- Made by reaction between phenol & formaldehyde
- Brittle & high shrinkage
- Fillers are used to reduce brittleness
- Used for electrical switches, auto molded parts, billiard balls
- Used as liner for rocket nozzles
Carbon Matrix
- Made from carbon fibers reinforced phenolics.
- Porous material can be re-impregnated.
- Pyrolysis (charring)
- Process may take up to 6 months
- High-temperature applications
- Liners for rocket nozzles, tiles for space shuttle nose cones, aircraft, race car, and truck brakes
- High energy absorption (specific heat)
Thermoplastic Matrix
- No shelf life
- Short processing cycle
- Higher ductility than thermosets
- Repairable
- Recyclable
- Higher viscosity than thermosets
- Requires high temperature for processing
- Tapes are stiff and boardy
Two types of Thermoplastic Resins
- Industrial thermoplastics (up to ~80°C) – Polyethylene (PE), Polyvinyl Chloride (PVC), Polymethylmethacrylate (PMMA), Polypropylene (PP), Polystyrene (PS), Acrylonitrile Butadiene Styrene (ABS)
- High-performance thermoplastics (up to ~300°C) – Poly-ether-ether-ketone (PEEK), Poly-ether-ketone-ketone (PEKK), Poly-ether-imide (PEI), Poly-phenylene sulfone (PPS), Poly sulfone
Thermoplastic Matrix- Fabrication
- Difficult due to high viscosity (compared to epoxy)
- Shear thinning
- Comingled fibers
- Power impregnation
Fillers
- Cost reduction
- Shrinkage reduction
- Improvement of mechanical properties
- Improvement of flame resistance
- Colorants, pigments
Metal Matrix
- Aluminum, titanium, magnesium, copper
- Short fibers such as SiC- particles, whiskers, fibers
- Piston ring inserts, pistons, connecting rods, high-temperature applications
Ceramic Matrix
- Oxides, carbides, borides, nitrides
- Short fibers such as SiC- particles, whiskers
- Made by chemical vapor deposition
- High-temperature applications
Polymer Nanocomposites
Structure of Clay Sheets
Clay sheets with intercalating ions
Different levels of clay structure
Replacing positive ions with long omium ions
Dispersion techniques
- High-pressure mixing technique
X-Ray pattern for samples mixed
- Relative intensity, 29 degrees
Minimum distance of particles
- Microscopic images and distribution plots of particle size
TEM of samples mixed
- Microscopic images
Variation of strain energy release rate
- Graph of strain energy release rate versus clay loading, with data points for different methods
High-speed mixing (10,000 rpm)
X-Ray Diffraction pattern
- Graph showing X-ray diffraction data for various samples and methods
Strain energy release rates
- Graph showing strain energy release rates for epoxy/clay samples
- Related to high-speed mixing method
Procedure to incorporate modified epoxy into long continuous carbon fibers
- Pictorial representation of procedure
Improvement in fracture toughness
Improvement of fatigue lives
Possible applications
- Barrier properties (obstruction to diffusion of small particles: CO2, flammability resistance).
- Fracture resistance
Carbon nanotube configurations
- Images
Three-roll milling machine
Variation of electrical conductivity
- Graph showing electrical conductivity versus CNT weight fraction
Possible applications
- Enhance electrical conductivity (lightning strike resistance, conductive adhesives).
- Uses for strain measurement
- Defect detection in composite structures
Aggregately conductive materials
- Diagrams illustrating different types of conductivity
Vessel with one layer
- Calculations and equations
Vessel with two layers
- Calculations and equations
Vessel with n layers
- Calculations and equations
Example on relative concentration
- Calculations and formulas related to epoxy resin and DETA amine concentration
Relative concentration
- Summary of concepts related to relative epoxy/hardener concentrations
Cured epoxy resin systems
- Aromatic rings, cross-link density, considerations influencing toughness, shrinkage, and chemical resistance
Lay up
- Methods for depositing layers of prepregs to create a laminate; considerations for avoiding sticking, resin flow, and volatile release
Curing and Consolidation
- Steps in curing and consolidation during the composite manufacturing processes, involving molecular cross-linking and layer compaction
- Factors determining cure percentage
Resin kinetics
-
- Various chemical reaction formulas and diagrams of epoxy and DETA molecule interactions
Degree of cure—Rate of cure
- Relationships and equations
Typical DSC curve for epoxy
- Graphical representation of heat flow versus time curve for different epoxy resins
Heat Transfer and Energy Balance
- Equations for composite thermal conductivity
- Data table of materials' properties
Heat generated
- Calculations and relationships related to heat generation during composite processing
Kinetic equations
- Equations for degree of cure and rate of cure, with different conditions
- Graphs/figures illustrating the kinetics of curing process
Different types of reactants
- Chemical structures/diagrams for various chemical reactants (ethylene glycol, orthophthalic acid, maleic acid)
Mold filling
- Equations/concepts regarding mold filling during LCM processes
- Diagrams illustrating flow patterns
Radial flow
Pressure
- Flow rate, flow front velocity, filling time
- Table of values and relationships related to pressure and filling times
- Consideration for various flow types (linear to convergent/divergent flow types)
Coefficient of Permeability
- Relation/equation between permeability, flow direction, material system, and fiber volume fraction
- Related table of permeability values for different materials
Permeability measurement
- Diagram/representation of design for measuring permeability.
- Description of two types of permeabilities (Rectilinear and Radial Flow)
Injection strategies
- Point injection.
- Edge injection.
- Peripheral injection.
Estimation of required filling time
- Calculations for determining filling time in different injection strategies (Point, Edge, Peripheral)
Ways to reduce fill time
- Decreasing viscosity (increase temperature).
- Increasing pressure (beware of potential fiber washing & deflection).
- Changing the reinforcement
- Reducing flow length (additional inlets)
Factors that affect the validity of equations
- Fiber washing, Race tracking at edges, Significant mold deflection, Significant cure pressure during injection, Non-Newtonian behavior of resin flow, Binder dissolution in resin (increase in viscosity), Preform variation
Problems and issues related to mold filling
- Summary of various issues related to mold filling in composite manufacturing processes.
- Specific concerns related to fiber variability, preform characteristics, and process conditions
Two types of flow in the preform
- Diagrams showing two types of flow observed/possible in fibrous preforms: Macro flow and Micro flow
Race tracking
- Diagram showing undesirable resin flow behavior (race tracking) and how it impacts resin-rich/dry-spot patterns
Occurrence of voids
- Considerations related to air/void removal and their impact
-
- Flow rate management with pressure to avoid air ingress
Fiber wetting
- Importance of fiber wetting, relationship to time and surface tension of components
Maximum mold filling time
- Concepts related to gel time and related parameters (e.g., NIP time) associated with mold filling
In mold cure
- Essential process of curing composite resins within a mold cavity, needing controlled reaction speed to prevent/limit negative outcomes
Considerations for curing
- Residual stresses, warping, void formation, and surface quality in curing systems
- Related defects in curing
Different types of resin flow and fiber deformation
- Diagrams describing different flow types (e.g., Resin percolation, Transverse flow, Interply slip, Interply shear)
Autohesion
- Molecular bonding at interfaces, leading to interface healing.
- Reptation theory, including relevant equations.
Degree of autohesion
- Formulas related to autohesion, considering time and viscosity
- Discussion related to different molding methods, how it will affect autohesion and its significance
Solidification
- Factors and parameters associated with the solidification (cooling) phase
- Degree of intimate contact and impact related to material/process parameters
- Equations associated with solidification
Bulk consolidation
- The pressure required for bulk consolidation (formula/concept)
- Impact of parameters on bulk consolidation (e.g., modulus relationship to different pressures and variables including number of layers and/or pressure/temperature )
Resin flow
- Percolation, transverse flow, intraply and interply shearing, cooperative flow.
- Equations and diagrams illustrating these types of flow associated with a fibrous preform in a composite system.
Different types of resin flow and fiber deformation
- Different resin flow categories associated with various geometry types or molding methods (e.g, consolidation, matched die, shaping, double curvature)
Autohesion
- Chemical bonding between dissimilar materials at interface
- Concept of autohesion and its role in eliminating interfacial issues
- Reptation theory's application in autohesion phenomenon
- Relevant diagrams/schematics
Degree of autohesion
- Formulas and relevant concepts related to autohesion (considering time and viscosity)
- Different molding methods' impact on autohesion and its implications/considerations
Consolidation, including discussion of the degree of intimate contact and considerations during resin flow. Include details/concepts about autohesion, pressure requirements, and related material properties.
- Description and relevant concepts of bulk consolidation and its relation to the molding process.
- Definitions and considerations of the degree of intimate contact and its impact on the composite system, including relevant factors impacting bonding.
- Pressure requirements and considerations for bulk consolidation, including the effect of different materials.
- Autohesion, including its role in eliminating interfacial gaps in the composite system, and considerations needed.
Thermoplastic Composites: Application, Advantages, and Disadvantages
- Summary of properties, advantages, and disadvantages
Materials for Filament Winding
- Fibers (E-glass, S-glass, carbon, Kevlar, combinations)
- Resins (Epoxy, polyester, vinyl ester) -Viscosity requirements linked to wet winding.
- Curing methods (room temperature or infrared heating methods).
Mold filling/Injection strategies
- In-mold cure
- Various Injection strategies (point/edge/peripheral method)
- Process control
- Flow considerations
- Molding aspects (e.g., considerations impacting mold designs)
Variables affecting mold filling time
- Different factors influencing overall mold filling time
- Approaches (strategies) for reducing filling time
- Factors affecting validity of filling time equations
Problems and issues related to mold filling
- Issues related to preform variability, process conditions, and related materials
Two types of flow
- Diagrams illustrating the two distinct modes of flow in the preform
Race tracking
- Diagram illustrating resin flow behavior in the context of racing (how it impacts resin-rich/dry-spot patterns)
Incidence of Voids
- Factors influencing void formation in mold cavity
- Prevention and management strategies.
- Pressure considerations during mold filling
Fiber wetting
- Importance related to avoiding void formation
- Factors influencing fiber wetting (time, surface tension of components)
Maximum mold filling time
- Concepts, related parameters (NIP time) for specific molding techniques.
In mold cure
- Aspects and factors impacting curing, time and flow, within composite mold cavity, Including considerations related to preventing/limiting negative outcomes
Consideration for curing, defects, their causes, process time impacts, and strategies for minimization
- Overall process issues in curing (residual stresses, warping, void formation, surface defects)
- Potential defects within a molding process.
Analysis of a production AFP machine
- Different steps in AFP machine, including aspects impacting efficiency.
- Issues related to reliability, recovery, tool movement considerations
Challenges in AFP machines (in aerospace manufacturing)
- Considerations impacting process efficiency/effectiveness
Future Outlook—Additive Manufacturing
- Expanding AFP technology, materials associated with additive manufacturing, newer/smaller AFP machinery
Two ends of the spectrum
- Different structural application types associated with AFP/ATL-related designs
Future outlook-- Smaller AFP machine
- Specs for a smaller AFP machine
Outline Thermoset Matrix and Thermoplastic Matrix
- Specific areas of attention and considerations
- Summary information about different composite types
Conclusion
- Summary of successes with thermoset matrix composites
- Considerations for improvements related to speed/efficiency, inspections, and fiber steering.
- Summary elements for thermoplastic matrix considerations linked to heating/temperature, interlaminar shear strength, distortion for structures, and future developments.
Natural Sciences and Engineering Research Council
- Summary information related to the Natural Sciences and Engineering Research Council of Canada, and collaborative projects/research initiatives.
Composite Manufacturing: Methods and Issues of Automation
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on the principles and processes of composite manufacturing. This quiz covers various materials, manufacturing steps, and the chemical properties involved in creating composite materials. From thermoset to thermoplastic matrix composites, challenge yourself and enhance your understanding of this field.