Rapid Prototyping - Fall 2024
Page 1: Introduction to Rapid Prototyping
Course Title: Manufacturing Processes: Rapid Prototyping
Instructor: Prof. Mamros
Class Information: MECH 355 | MWF 1:00-1:50 pm | Dana 137
Page 2: Chapter Overview
Chapter Focus: Rapid Prototyping Processes and Operations
Page 3: Overview of Rapid Prototyping
Typical Products: Can be metallic and nonmetallic parts for:
Product design analysis
Evaluation
Finished products
Alternative Processes: Includes:
Machining
Casting
Molding
Fabricating
Advantages:
High capital costs and long lead times for production tooling
Useful for design evaluation and troubleshooting
Page 4: Prototype Production Process
Iterative Driven Process:
Discovery of errors
Derivation of better design solutions from earlier prototypes
Considerations:
Time-consuming and resource-intensive
Page 5: Rapid Prototyping Technology
Definition: Speeds up iterative product development considerably.
Other Names:
Desktop manufacturing
Digital manufacturing
Solid free-form fabrication
Page 6: Advantages of Rapid Prototyping
Manufacturing Speed: CAD models can be produced in hours.
Subsequent Operations: Prototypes can be used in further production processes.
Tooling Production: Rapid tooling for manufacturing operations.
Mass Customization: Achievable through distributed manufacturing.
Page 7: Disadvantages of Rapid Prototyping
Main Drawbacks: Two primary disadvantages highlighted but unspecified in details.
Page 8: Categories of Rapid Prototyping
Subtractive: Material removed from a larger workpiece.
Additive: Material built up incrementally.
Virtual: Advanced computer-based visualization techniques.
Page 9: Characteristics of Additive Technologies
Supply Layer Creation Techniques: Differences in processes may include:
Stereolithography: Liquid layer curing using photopolymerization.
CLIP: Similar to stereolithography but achieves different results in time and resolution.
Other methods listed with materials used and processes defined, including:
Fused-deposition modeling (FDM)
Binder jetting
Selective Laser Sintering (SLS)
Page 10: Fused-Deposition Modeling (FDM)
Description: Standard 3D printing where a nozzle extrudes material (size typically 0.05-0.12 mm).
Accuracy: Dimensional accuracy as fine as 0.025 mm.
Common Filaments: Various polymers suitable for the process.
Page 11: Support Material in 3D Printing
Usage: Necessary for parts with protruding sections to maintain structural integrity.
Page 12 and 13: Mechanical Properties of Materials
Details: Mechanical properties of selected materials specific to rapid prototyping discussed, but specifics not listed in the notes.
Page 14: 3D Printing Quiz
Resource: Link provided for an ASME quiz on 3D printing materials.
Page 15: Additive Manufacturing (AM) Methodology
Highlight: All build parts are constructed layer by layer; methods vary based on slice production.
Software Requirement: Requires specialized software with STL files.
Trend: Mention of makerspaces.
Page 16: Photopolymerization Process: SLA
Description: Stereolithography with tolerances around 0.0125 mm.
Cycle Times: Ranges from a few hours to one day.
Investment: Equipment cost is high (between $100K-$400K).
Page 17: Continuous Liquid Interphase Production (CLIP)
Process: Layers created by digital light processing (DLP), requiring cleaning and curing.
Production Rates: Extremely high compared to other AM processes.
Page 18: Material Jetting Processes
Definition: Includes processes like drop on demand (DOD), requiring low viscosity materials.
Resolution: Achieves higher resolution due to thinner layers.
Page 19: Powder Bed Processes
Overview: Utilizes powder as workpiece material with critical steps in preparation and spreading.
Challenges: Risks of powder explosions or fires from static discharge.
Page 20: Selective Laser Sintering (SLS)
Process Description: Sintering of nonmetallic powders to form individual objects, suitable for various materials.
Post-Processing: Loose particles typically brushed off and does not require curing.
Page 21: SLS Advantages and Disadvantages
Advantages:
Material isotropy and accurate properties.
Doesn't require support materials.
Disadvantages:
Parts may experience shrinkage and warpage due to thermal effects.
High costs of machinery ($300K - nearly $1M).
Page 22: Electron Beam Melting (EBM)
Process: Melts titanium or cobalt-chrome powder in a vacuum for metal prototypes.
Energy Efficiency: Highly energy-efficient process.
Page 23: Binder Jet Printing (BJP)
Method: Uses a binder material on layered powder to bond particles incrementally.
Outcome: Allows for different material flexibility and may result in porous parts.
Page 24: BJP for Rapid Tooling
Combination: BJP can be used with various processes to produce denser parts; common materials include titanium and stainless steel.
Page 25: Rapid vs. Conventional Tooling
Focus: Identification of the biggest disadvantage of rapid tooling but specifics unprovided.
Page 26: Composite Filaments
Challenge: Orientation of fibers during loading considered important for strength.
Page 27: Other Processes in Rapid Prototyping
Additional Methods:
Laminated object manufacturing
Laser engineered net shaping
Friction stir modeling
Wire and arc AM
Page 28: Investment Casting Lab Process
Steps to Complete:
Pattern creation
Tree assembly
Insertion into flask
Investment filling
Wax melt-out/burnout
Filling mold with metal
Cooling
Finishing workpiece
Page 29: Emerging Applications of AM
Applications: Includes bioprinting, architectural applications, and in-space manufacturing by NASA.
Page 30: 3D Printers Made
Highlight: Example of direct manufacturing processes discussed.
Page 31: Smart Materials Overview
Inclusion: Information sourced from Shehata et al. discussing smart materials in the context of rapid prototyping.
Page 32: Design Considerations for Additive Manufacturing
Concerns:
Warping due to thermal stresses and shrinkage.
Tolerances should be symmetric.
Orientation, dimensions, and surface treatment matters based on material and machinery used.
Page 33: Further Design Considerations
Thickness Requirements: For FDM, wall thickness should be at least four times the layer thickness.
Page 34: Additional Design Considerations
Size Impact: Large parts are more likely to warp; build time relates to material volume.
Complexity in Design: Noted that complex geometries do not necessarily add to cost.
Page 35: Example Problem for FDM Calculation
Problem Statement: Details provided for calculating production time under different conditions, including dimensions and infill percentage.
Solution: Steps required to find the answer.
Page 36: Fiber Reinforced Filament Reference
Resource: Link provided regarding fiber-reinforced 3D printing strategies.
Page 37: Economics of Additive Manufacturing
Cost Breakdown:
πΆπΆππ = total cost = material cost + setup cost + machinery cost + finishing operations cost.
Page 38: Exploring Other Filaments
Discussion Prompt: Engaging students to share experiences with various filament types in use.
Page 39: Reverse Engineering Process for Dimensional Details
Steps Included:
Manual Measurement
Optical Measurement
Creating a 3D model and inspecting against the physical product.
Page 40: AM in Food Industry
Engagement Task: Suggested to list five interesting points from a related video discussion.
Page 41: Conclusion
Message: Thank you for attending the session.