3D Printing and Additive Manufacturing

The following sections are included:

• DEDICATION
• FOREWORD
• PREFACE
• ACKNOWLEDGMENTS
• ABOUT THE AUTHORS
• LIST OF ABBREVIATIONS
• CONTENTS

The competition in the world market for manufactured services and products has intensified tremendously in recent years. It has become important, if not vital, for new products to reach the market as early as possible, before the competitors. To bring products to the market swiftly, many of the processes involved in the design, testing, manufacture, marketing and distribution of the product have been squeezed, both in terms of time and material resources. The efficient use of such valuable resources calls for more efficient tools and effective approaches in dealing with them, and many of these tools and approaches have evolved. They are almost entirely technology-driven, inevitably involving the computer, a result of the rapid development and advancement in such technologies over the last few decades…

The following sections are included:

• Fundamental Automated Fabrication Processes
• Process Chain
• 3D Modelling and Support Design
• Data Conversion and Transmission
• Checking and Preparing
• Building
• Post-Processing
• References
• Problems

Most liquid-based additive manufacturing (AM) systems build parts in a vat of photocurable liquid resin, an organic resin that cures or solidifies under the effect of exposure to light, usually in the UV range. The light cures the resin near the surface, forming a thin hardened layer. Once the complete layer of the part is formed, it is lowered by an elevation control system to allow the next layer of resin to be coated and similarly formed over it. This continues until the entire part is completed. The vat can then be drained and the part removed for further processing, if necessary. There are variations to this technique by the various vendors and they are dependent on the type of light or laser, method of scanning or exposure, type of liquid resin and type of elevation and optical system used. Another method is by jetting drops of liquid photopolymer onto a build tray via a printhead, akin to inkjet printing and curing them with UV light. Again, there are variations to the technique depending on the types of resin, exposure, elevation and so on.

Solid-based additive manufacturing (AM) systems utilise solids as the primary medium to create the part or prototype. As such, they are very different from the liquid-based photo-curing systems described in Chap. 3. They are also different from one another in that the primary form of solid materials in some systems may come as filaments or wires, some as sheets or rolls while others may be as pellets. A special group of solid-based AM systems that uses powder as the medium will be covered separately in Chap. 5.

This chapter describes the special group of solid-based additive manufacturing (AM) systems, which primarily use powder as the basic medium for printing. Some of the systems in this group, like Selective Laser Sintering (SLS), bear similarities to the liquid-based AM systems described in Chap. 3, that is, they generally have a laser to “draw” the part layer-by-layer, but the medium used for building the model is a powder instead of photocurable resin. Others, like Color Jet Printing (CJP) has similarities with the solid-based AM systems described in Chap. 4. The common feature among these systems described in this chapter is that the material used for building the part or prototype is invariably powder based.

The following sections are included:

• STL Format
• STL File Problems
• Consequences of Building a Valid and Invalid Tessellated Model
• STL File Repair
• Other Translators
• Standards for Representing Additive Manufactured Objects
• Other Standards on AM
• References
• Problems

The following sections are included:

• Application — Material Relationship
• Finishing Processes
• Applications in Design
• Applications in Engineering, Analysis and Planning
• Applications in Manufacturing and Tooling
• Aerospace Industry
• Automotive Industry
• Jewellery Industry
• Coin Industry
• Tableware Industry
• Geographic Information System Applications
• Art
• Architecture
• Building and Construction
• Fashion and Textile
• Weapons
• Musical Instruments
• Food
• Movies
• Marine and Offshore
• References
• Problems

The following sections are included:

• Planning and Simulation of Complex Surgery
• Customised Implants and Prostheses
• Design and Production of Medical Devices
• Forensic Science and Anthropology
• Visualisation of Bio-Molecules
• Bionic Ear
• Dentistry
• References
• Problems

The following sections are included:

• Technical Evaluation Through Benchmarking
• Industrial Growth
• Future Trends
• References
• Problems

The following sections are included:

• APPENDIX: LIST OF AM COMPANIES
• COMPANION MEDIA PACK ATTACHMENT
• COMPANION MEDIA PACK USER GUIDE