3D Printing

Technology, Applications, and Selection

Rafiq Noorani

• Publisher: CRC Press
• Year: 2017
• ISBN:
  9781351651547
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

3D Printing is a faster, more cost-effective method for building prototypes from three-dimensional computer-aided design (CAD) drawings. 3D Printing provides a fundamental overview of the general product design and manufacturing process and presents the technology and application for designing and fabricating parts in a format that makes learning easy. This user-friendly book clearly covers the 3D printing process for designers, teachers, students, and hobbyists and can also be used as a reference book in a product design and process development.

1

Introduction

1.1 Introduction

Mastering the art of 3D printed components, sub-assemblies, and products is vital for any product development process. Over the last few years, new and exciting technologies have emerged that are changing the ways that products have been launched. 3D printing (3DP) is an example of such technology, which is revolutionizing the design and manufacturing of new products. This technology is being used to fabricate physical solid models for early verification of concepts, e.g., form, fit, and function as well as reducing lead-times for product development [1].

Not long ago, 3DP was only associated with prototyping. Nowadays, 3DP technology has come a long way from basic rapid prototyping (RP) machines of the 1980s, and 3DP is more than just prototyping with today’s materials and technology. 3DP process offers transformative advantages at every part of the manufacturing process from initial concept design to production of final products to be marketed, and all the steps in between. There is extremely large variety of 3D printers and technologies available these days; therefore, it is important to be thoroughly informed in order to choose the right 3D printer for specific applications.

First, 3DP technology as we know it today emerged in 1980s, and a thought of having a personal mini 3DP workstation was a dream. Even just a few years ago, in-house 3DP technology was enjoyed only by a very few professional design engineers, and the applications were very limited to creation of concept models and simple prototypes. Once considered a luxury, 3DP has proven to yield long-term strategic value by enhancing design-to-manufacturing capabilities and reducing the time to market final products. 3DP technologies have allowed an ever-growing number of creators, designers, engineers, physicians, researchers, academics, and manufacturers to unleash all the benefits of RP/3DP in-house across the entire design process.

Leading manufacturing companies harvested the full power that 3DP technology has to offer and are now using 3DP to evaluate more concepts in short time to improve the decision-making and design process early in product development. As the design process moves forward, technical decisions are iteratively tested at every step to guide decisions, to achieve maximum performance, minimize manufacturing costs, and deliver the highest quality. In the preproduction phase of manufacturing process, 3DP allows accelerated first concept product development and assists with troubleshooting of any problems that may arise. In the final production stage of manufacturing process, 3DP allows for higher productivity, increased flexibility, reduced logistics costs, economical optimization, improved product quality, reduced product weight, less overall parts in the assembly, and greater efficiency in a growing number of industries [2].

In this opening chapter, 3DP will be defined. In addition, study of 3DP history and the importance of this technology for product development will be covered as well. Applications of this technology through a case study and future trends will also be discussed.

1.2 The World of 3DP

The field of 3DP encompasses a wide variety of new methods, technologies, and applications that have already stimulated some fascinating research. Many companies have found exciting new ways to improve product development processes and enhance profitability. The prospect of being a part of this new technology with its promise of radical improvement in the way business is done should be as highly motivating to the reader, as it is to the author. In this section, some definitions and applications of 3DP will be discussed, and examples of some companies that are using 3DP will be given.

1.2.1 What Is 3DP?

3DP, as described in this text, refers to the fabrication of a physical, 3D part of arbitrary shape directly from a numerical description (typically a CAD model) by a quick, totally automated, and highly flexible process without any tooling. According to Wohler’s Report 2014, 3DP is defined (as also defined by ASTM International Committee F42) as “fabrication of objects through the deposition of a material using a print head, nozzle, or other printer technology.” However, the term is often used synonymously with additive manufacturing (AM). AM is a broader term that encompasses building 3D physical models. Prototypes, patterns, and tooling components using various materials such as plastics, ceramics, metals, etc. [3].

1.2.2 What Is RP?

RP is a technology that also refers to the fabrication of 3D part of an arbitrary shape directly from a numerical description by a quick, totally automated, and flexible process. RP is the term that has been used since 1989 when the RP process was invented. From 1989 to 2005, the additive technology was known as RP. After nearly two decades of the use of RP, the personal 3DP revolution started with an open-source project known as RepRap. Since then, the growth of 3DP has been phenomenal, exceeding over 72,000 units sale in 2013. The difference between RP and 3DP is minimal and the two terms can be used interchangeably. In particular, 3DP is associated with machines that are lower in relative price (<$5000) and overall functional capability. Both RP and 3DP are part of AM.

As it was mentioned before, 3DP is a relatively new technology that creates profound effect on the product development process of design and manufacturing industries worldwide. 3DP technology can prototype parts very rapidly in most cases, i.e., in hours rather than in days or weeks. This technology is quickly expanding to include rapid tooling (RT) and rapid manufacturing (RM). RP, tooling, and manufacturing are technologies that are also widely used these days. 3DP can be sometimes referred to as desktop manufacturing, direct CAD manufacturing, and instant manufacturing.

The unique characteristic of 3DP manufacturing process is that it makes physical prototypes one layer at a time. Therefore, following terms that emphasize this layer-by-layer manufacturing characteristic are sometimes used as well: layered manufacturing, material deposit manufacturing, and material addition manufacturing.

The last group of terms for 3DP emphasizes the words “solid,” “freeform,” and “fabrication.” This group of terms includes solid freeform fabrication and solid freeform manufacturing. The word “solid” refers to the final solid state of the material, although the initial state may be solid, liquid, or powder. The word “freeform” stresses the fact that 3DP can prototype complex shapes with little or no constraint on shape form. 3DP is also related to “automated fabrication,” which describes new technologies for generating 3D objects from computer files in a completely automated process.

1.2.3 The History of 3DP

Charles Hull, the founder of 3D Systems, is consider as the founder of 3DP. He obtained his first patent for 3DP in 1984 for his stereolithography apparatus (SLA), which uses UV light to cure photopolymer resin in a vat to make prototypes. The principle of 3DP is that a software can slice a 3D object into layers of particular thickness and a machine can stack them together one above the other, forming the 3D part. In the early 1980s, the computer-aided design (CAD) was still in its infancy, and Mr. Hull had a challenge of how to translate the CAD file in a file format that the 3D printer can interpret and print. Again, with the help of a consulting firm (Albert Consulting Group), he developed the stereolithography (STL) file format that could be used by any 3DP machine. Although people talk about some limitations of the STL file, today, it is still the de facto standard for 3DP process. We shall talk more about this STL file in the next chapter [4].

Scott Crump, the founder of fused deposition modeling (FDM) printing process, developed the FDM technology in 1989 and founded the Stratasys company. Crump also developed acrylonitrile butadiene styrene (ABS) materials for the FDM machine that is widely used by a vast majority of 3D printers today. 3D Systems and Stratasys are the two biggest 3DP companies in the world. Over the years, these two companies have acquired other companies with different technologies and have truly become the best and biggest 3DP companies in the world.

Dr. Carl Deckard and Dr. Joe Beaman developed selected laser sintering (SLS) process at the University of Texas in the mid-1980s independently of the SLA and FDM processes. While SLS and FDM were successful in making plastic and nylon parts, none of the technology could make prototypes in metals. SLS was the only technology at that time to make prototyping parts in metals. The technology was originally sold by DTM Corporation, which was later purchased by 3D Systems.

In the early 1990s, the Massachusetts Institute of Technology (MIT) invented inkjet 3D printing, known as 3DP. The license for 3DP was given to Z Corp. In the early 2012, 3D Systems bought the company to acquire all the associated patents and licenses.

Many of the industrial patents of 3D Systems and Stratasys expired a few years ago. Especially, the expiration of FDM technology started the consumer 3DP technology, as we know it today. The 3DP revolution was started in 2005 with the open-source project called RepRap. The purpose of the RepRap project is to make a machine that can replicate itself. With the participation of entrepreneurs and hobbyists, the 3DP revolution is going on in full swing. These 3D printers are very inexpensive (<$5000) but very robust in most cases. Most 3D printers use FDM and stereolithography technology. They use open-source hardware and software to operate. With the advancement of computer technology and electronics and software, these 3D printers are the future. The historical growth of 3D printers since 2005 bears testimony to this effect. Some of the most popular consumer 3D printers of the market are MakerBot Replicator and FormLabs 1+. We shall describe some of the most popular 3D printers in the next few sections of this chapter.

1.2.4 Applications of 3DP

There are many types and classes of physical prototypes, but their main purpose is to minimize risk during the product development process. Some of the specific applications of 3DP technology are mentioned below:

• Communication of product characteristics
• Engineering concept definition
• Form, fit, and function testing
• Engineering change clarification
• Client presentations and consumer evaluations
• Bid proposals and regulation certification
• Styling, ergonomic studies
• Facilitate meeting schedule and making milestones
• Masters for silicone rubber tooling
• Masters for spray metal tooling (all processes)
• Masters for epoxy tooling to be used for injection molding
• Master/Pattern for investment casting
• Tooling for injection molding

1.2.5 The Basic Process of 3DP

There are many differen...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Dedication Page
• Contents
• Book Organization
• Preface
• Acknowledgments
• About the Author
• 1. Introduction
• 2. How Does 3D Printing Work?
• 3. Design of a 3D Printer
• 4. Calibrating the 3D Printer
• 5. Materials for 3D Printing
• 6. Classifications of Rapid Prototyping and 3D Printing Systems
• 7. Scanning and Reverse Engineering
• 8. Common Applications of 3D Printers
• 9. 3D Printing in Medicine
• 10. How to Select Rapid Prototyping and 3D Printer
• Appendix A: Glossary of Terms
• Appendix B: List of Abbreviations
• Appendix C: MATLAB Program for Expert System
• Index