1、Studies into Additive Manufacturing for In-Space ManufacturingFor more information or to order a book, contact: SAE INTERNATIONAL 400 Commonwealth Drive Warrendale, PA 15096 Phone: +1.877.606.7323 (U.S. and Canada only) or +1.724.776.4970 (outside U.S. and Canada) Fax: +1.724.776.0790 Email: Custome
2、rServicesae.org Website: books.sae.orgStudies into Additive Manufacturing for In-Space Manufacturing Edited by Rani Elhajjar and Tracy R. Gill Warrendale, Pennsylvania, USA Copyright 2016 SAE International eISBN: 978-0-7680-8374-3Copyright 2016 SAE International. All rights reserved. No part of this
3、 publication may be reproduced, stored in a retrieval system, distributed, or transmitted, in any form or by any means without the prior written permission of SAE International. For permission and licensing requests, contact SAE Permissions, 400 Commonwealth Drive, Warrendale, PA 15096-0001 USA; e-m
4、ail: copyrightsae.org; phone: +1-724-772-4028; fax: +1-724-772-9765. Library of Congress Catalog Number 2014944059 SAE Order Number SRP-001 DOI http:/dx.doi.org/10.4271/srp-001/ Information contained in this work has been obtained by SAE International from sources believed to be reliable. However, n
5、either SAE International nor its authors guarantee the accuracy or completeness of any information published herein and neither SAE International nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the underst
6、anding that SAE International and its authors are supplying information, but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. ISBN-Print 978-0-7680-8373-6 ISBN-PDF 978-0-7680-8374-3
7、 ISBN-epub 978-0-7680-8376-7 ISBN-prc 978-0-7680-8375-0 To purchase bulk quantities, please contact SAE Customer Service e-mail: CustomerServicesae.org phone: +1.877.606.7323 (inside USA and Canada) +1.724.776.4970 (outside USA) fax: +1.724.776.0790 Visit the SAE Bookstore at books.sae.org 400 Commo
8、nwealth Drive Warrendale, PA 15096 E-mail: CustomerServicesae.org Phone: +1.877.606.7323 (inside USA and Canada)+1.724.776.4970 (outside USA) Fax: +1.724.776.0790v Table of Contents Preface vii Introduction ix Chapter 1: Extrusion and 3D Printing of Recycled ABS Filament for Use in FDM Lessons Learn
9、ed . 1 Aleksey Yermakov, Brandon Hitter, Tressa Norden, and Anthony Demeuse Chapter 2: Mechanical Properties of 3D-Printed Recycled ABS Materials for FDM Applications 11 Jon Wolgamott, Alexandra Slay, Keith Anderson, and Gabriella Santarosa Chapter 3: Effects of Orientation Angle on the Mechanical P
10、roperties of FDM Parts 19 Jon Wolgamott, Alexandra Slay, and Keith Anderson Chapter 4: Finite Element Modeling of 3D Printed Materials Using Unit Cell Methods 27 Seyedmohammad S. Shams and Daniella M. Perazzo Chapter 5: Design of a Carbon-Fiber Reinforced Fused Deposition Modeling Modular Wrench Too
11、l 37 Alex Francis, Ben Huberty, Nicole Przybyla, and Alex Seidcheck Chapter 6: Carbon Fiber Reinforced 3D Printed Ratchet: Feasibility and Application in Deep Space Missions . 53 Bryan Sinkovec and John Emholtz Chapter 7: High Performance 3D Printed Carbon-Fiber Reinforced Crowfoot Adaptive Tool 63
12、Kelly Scott and Brett Sweeney Chapter 8: A Recyclable ABS/Carbon-Fiber Reinforced Locking Pliers Tool Using Fused Deposition Modeling 3D Printing Technique 71 Joel Klopstein and Bill Merschdorf About the Authors . 79 About the Editors 82vii Preface The annual X-Hab Academic Innovation Challenge, ini
13、tiated in 2011, provides university students with the opportunity to be on the forefront of innovation. The X-Hab Challenge, for short, is designed to engage and retain students in Science, Technology, Engineering, and Math (STEM). The National Aeronautics and Space Administration (NASA) identifies
14、necessary technologies and studies for deep space missions and invites universities from around the country to develop concepts, prototypes, and lessons learned that will help shape future space missions and awards seed funds to design and produce functional products of interest as proposed by unive
15、rsity teams according to their interests and expertise. Universities propose on a variety of projects suggested by NASA and are then judged on technical merit, academic integration, leveraged funding, and outreach. The universities assemble a multidisciplinary team of students and advisors that inve
16、st months working together, developing concepts, and frequently producing working prototypes. Not only are students able to gain quality experience, working real-world problems that have the possibility of being implemented, but they work closely with subject matter experts from NASA who guide them
17、through an official engineering development process. During the 2014-2015 academic year, the University of Wisconsin-Milwaukee was selected to execute a project entitled Design of a Carbon-Fiber/Fused Deposition Modeling Spacecraft Structural Fabrication System. The project was sponsored by NASAs In
18、-Space Manufacturing Project, based at the Marshall Space Flight Center, but the team was able to get the benefit of experts from other NASA centers as well. The team studied 3D printing technology applications for creating and recycling tools on long-term space missions. The project showed very pro
19、mising results, and this book is a compilation of findings from the project and hopefully the first of more of its kind as a result of an X-Hab Challenge project. Tracy R. Gill, NASA, Kennedy Space Center ix Introduction Three-dimensional (3D) printing or additive manufacturing (AM) using thermoplas
20、tic materials has had a profound impact on the engineering field. The ability to use AM for one-off special parts or as a tool for conceptualizing complex details has been applied successfully in various applications. AM using plastics has been applied in areas ranging from rapid prototyping of comp
21、lex parts to brain surgeons employing models of patient brains to visualize the surgery procedures in advance. However, the use of plastics in additive manufacturing is coupled with an increased public awareness on the need for recycling technologies that will limit the amount of waste going to the
22、landfills. Advances in AM for space exploration has also been a subject of growing interest as ideas and concepts of long-range space missions evolve. In partnership with the National Space Grant Foundation and NASA, students from the University of Wisconsin-Milwaukee participated in the 2014-15 X-H
23、ab Academic Innovation Challenge. This program is a university-level challenge designed to engage and retain students in science, technology, engineering, and math and simultaneously engage students in pressing research and design topics of interest to the space exploration community. NASA has recog
24、nized the need for new AM technologies not only for environmental sustainability but also for recycling capabilities for replacement parts on long-range spacecraft missions. NASA has embarked on an ambitious program to integrate additive manufacturing techniques and to develop processes for the micr
25、ogravity environment. The most recent example of this program is the successful launch and deployment of the first 3D printer on the International Space Station. In this one-year effort, students were required to meet a series of milestones to design, manufacture, and test their ideas in close coope
26、ration with members of the NASA Exploration Augmentation Module (EAM) concept team. The X-Hab approach provides a unique method by placing the student teams on the NASA mission-critical path for the technologies considered. The participants in this project were tasked with thinking of new solutions
27、using AM that would simultaneously be recyclable with minimal loss in mechanical properties but also have the capacity for high mechanical properties. The challenge outlined broad criteria for the requirements, including the cradle-to-cradle approach without pre-conceived judgment on the results. Pr
28、evious research has shown that the mechanical properties of 3D printed parts depend not just on the type of filament material used, but also on the various build parameters associated with AM. Various process parameters have been found to influence the mechanical properties of AM parts; these includ
29、e raster orientation, air gap, bead width, color, and model temperature. However, there has been a limited understanding of the process development necessary for recycling 3D printed parts from the procedure from breaking up the component to creating the filament and finally to printing with a recyc
30、led filament. Working in interdisciplinary teams, the participant teams investigated the use of recycled materials, characterization, testing, modeling, and tool development. The underlying philosophy adopted in these papers is the ability to use a strut-and-tie approach that integrates reusable car
31、bon-fiber tension ties for tension zones. All materials are designed so they can be recycled or reused. The tools developed show that it is possible to employ thermoplastic polymer materials fabricated using AM together with reusable and flexible high-performance carbon-fiber-based composite ties. T
32、he AM printed part is completely recyclable, whereas the carbon-fiber composite ties are repurposed into new structural configurations without loss in properties. The results of this project encompass a series of interconnected studies exploring the issues surrounding 3D printing in a space environm
33、ent. In the first chapter, the participants discuss the lessons learned in processing of recycled thermoplastic filaments. A discussion is presented of the necessary constraints on fiber diameter and contamination control. The criticality of process control on the print process is examined in the se
34、cond chapter on the effects of recycling. The materials used showed significant resiliency through the recycling process in all the mechanical loading modes studied. Coupled with the analysis of scanning electron microscopy results, one can see interesting connections between the microstructural par
35、ameters and the mechanical behavior. The third chapter looks into the effects of orientation angles and print parameters on the mechanical behavior. Careful selection of the microstructure can be targeted to specific multiaxial stress states. The fourth chapter continues the microstructural analysis
36、 but investigates the behaviors using unit cell models and the finite element method. The final four chapters present case studies of tools that are considered part of the spacecrafts tool chest. For example, incorporating the reusable carbon-fiber-based composite straps in the ratchet tool shows ho
37、w a shorter print time can be realized while simultaneously preserving valuable power. The student papers reveal how a sustainable method can be conceived and implemented for recycling, weight reduction, and shorter print times. Finally, special thanks to the National Space Grant Foundation, The Wis
38、consin Space Grant Consortium, and the NASA Marshall Space Flight Center engineers, Niki Werkheiser, Mallory Johnston, and Quincy Bean for their assistance and guidance on this project. The support of all the NASA engineers who attended the conference calls and provided feedback to the students over
39、 the yearlong project is also greatly appreciated. Rani Elhajjar, University of Wisconsin- MilwaukeeChapter 1: Extrusion and 3D Printing of Recycled ABS Filament for Use in FDM Lessons Learned Aleksey Yermakov, Brandon Hitter, Tressa Norden, and Anthony Demeuse3 Abstract The main component of this s
40、tudy is exploration of the ability to recycle previously 3D printed acrylonitrile butadiene styrene (ABS) parts, as well as to study the effects of the recycling process on the mechanical properties of the material. A number of challenges were encountered which may impact the ability to implement a
41、3D printing environment utilizing 100% recycled feedstock. Consistency of the filament extrusion process, possible sensitivity of fillers used in the ABS to the recycling process, and the critical nature of the 3D printers hot end design were all determined to be factors important to the ability to
42、reliably recycle 3D printed ABS objects. The issues encountered were addressed and a successful printing environment established, though room for improvement exists. 1. Introduction In general terms, fused deposition modeling (FDM) 3D printing involves the fabrication of a three dimensional object v
43、ia the deposition of molten thermoplastic in discrete layers comprising cross-sectional areas of the object. Most such machines are fed a filament of thermoplastic feedstock, which is then heated to a prescribed melting temperature via a heating element located near the extrusion tip. The motivation
44、 behind this paper is to document the attempts to facilitate a 3D printing environment using 100% recycled ABS feedstock. With the ability to recycle and reinforce 3D printed parts, the useful life of a finite quantity of FDM feedstock could be greatly increased. Although ABS is an established engin
45、eering plastic with a significant body of research behind it, 3D printing with 100% recycled ABS is a much less explored subtopic. A critical component to this objective is the successful recycling of previously-printed objects. In order to avoid porosity of the recycled filament, the objects must b
46、e broken down into pieces with sufficiently small dimensions. The broken down material must then be extruded at a controlled temperature to dimensions specific to the 3D printer into which it will be fed. Special care must be taken to ensure quality of the produced feedstock in order to avoid cloggi
47、ng of the 3D printer. Such clogs can lead to issues from incomplete reproduction of the desired print geometry to complete failure of a print. In this study the authors investigate the issues involving extrusion and 3D printing of recycled ABS filament. Achieving consistent filament dimensions durin
48、g the extrusion process proved critical. A range of acceptable diameters was defined, and measures taken to ensure that all produced filament was within this range. Then, contamination of the filament with particles of foreign materials as small as 300 m became an issue. The granulator in which prev
49、iously-printed parts were ground up for re-extrusion had been used to process other thermoplastics with various reinforcing agents, and despite cleaning that was performed before granulation of ABS some contaminants likely remained. Additionally, some contamination of the extruder used to fabricate recycled filament appeared likely. A purge procedure was implemented after identification of this issue. Despite the previous measures, severe clogging was encountered when attempting to 3D print using the recycled feedstock. Three separate hot-ends were used when attempting to ide
