Precision and Energy Usage for Additive Manufacturing

Proceedings of the ASME 2013 International Mechanical Engineering Congress and Exposition IMECE2013 November 15-21, 2013, San Diego, California, USA IMECE2013-65688 PRECISION AND ENERGY USAGE FOR ADDITIVE MANUFACTURING Lee Clemon Department of Mechanical Engineering University of California Berkeley, California 94720 Anton Sudradjat Department of Mechanical Engineering University of California Berkeley, California 94720 Maribel Jaquez Department of Mechanical Engineering University of California Berkeley, California 94720 Aditya Krishna Department of Mechanical Engineering University of California Berkeley, California 94720 Marwan Rammah Department of Mechanical Engineering University of California Berkeley, California 94720 David Dornfeld Department of Mechanical Engineering University of California Berkeley, California 94720 initial and process resource investment. The energy and quality assessment methods developed in this study are applicable to a greater variety of additive manufacturing technologies and will assist designers as additive manufacturing becomes more production friendly. The presented data also provides designers and production planners insight for improvements in the process decision making. ABSTRACT Market pressures on manufacturing enterprises incentivize minimum resource consumption while maintaining part quality. Facilities with advanced manufacturing tools often utilize rapid prototyping for production of complicated or specialty parts. Additive manufacturing offers an alternative to traditional production methods which are often time and resource expensive. This study aims to explore part quality and energy usage for additive manufacturing through a focused study of Fused Deposition Modeling and Photopolymer Jetting technologies. A control part is developed for maintaining test consistency across different machines. The control part design consists of various positive and negative features including width varied slots and walls, ramps, and curved features so that the manufacturing of different surfaces may be investigated. Several different machine models are tested to evaluate precision for a variety of applications. Part quality is quantified by measuring the surface roughness in two directions for the control test part printed on each machine. Qualitatively, part quality is assessed by positive and negative feature resolution. High quality machines resolve features closely to design specifications. Lower quality machines do not resolve some features. In addition to exploring the effects of advertised print precision, layup density is varied on two machines. Advertised print resolution does not well represent the achievable feature sizes found in this study. Energy usage is quantified by measuring electricity demands while printing the control part on each of the five different machines. Power consumption in additive manufacturing is found to follow a distinct pattern comprised of standby, warm up, printing and idle phases. Measurement and analysis suggest a relationship between the precision of these machines and their respective energy demand. Part quality is found to generally improve with increased INTRODUCTION Additive Manufacturing (AM) is the process of joining material to create 3D objects, typically layer by layer. As a result of the additive approach, AM can build complex geometries that other methods are not capable of fabricating One challenge AM faces is the lack of developed standards. Intact standards drive increased quality and market acceptance, thus promoting the adaptation of technologies. An ASTM International Committee F42 on AM Technologies was formed in 2009 to establish industry standards for the adoption and further implementation of AM [2]. Process characterization of printing energy to material weight is available in the literature but there is a lack of characterizing printing energy in regards to feature quality [3], [4]. This paper aims to explore quality and energy usage for AM and fill this white space in the knowledge base. The motivation for the research stems from the work done in [5], [6], [7], [8], and [9] which conclude that machine tools operate at fixed energy levels during different phases of operation. However, most related research until now has focused on subtractive manufacturing and therefore, there is a need to explore the applicability of this principle to AM. Downloaded From: http://proceedings.asmedigitalcollection.asme.org/ on 07/14/2014 Terms of Use: http://asme.org/terms Copyright © 2013 by ASME