Objectives. To determine the production tolerance of four commercially available additive manufacturing systems. Methods. By reverse engineering annex A and B from the ISO_12836;2012, two geometrical figures relevant to dentistry was obtained. Object A specifies the measurement of an inlay shaped object and B a multi-unit specimen to simulate a four-unit bridge model. The objects were divided into x, y and z measurements, object A was divided into a total of 16 parameters and object B was tested for 12 parameters. The objects were designed digitally and manufactured by professionals in four different additive manufacturing systems; each system produced 10 samples of each objects Results. For object A, three manufacturers presented an accuracy of <100 mu m and one system showed an accuracy of <20 mu m For object B, all systems presented an accuracy of <100 mu m, and most parameters were <40 mu m. The standard deviation for most parameters were <40 mu m Significance. The growing interest and use of intra-oral digitizing systems stresses the use of computer aided manufacturing of working models. The additive manufacturing techniques has the potential to help us in the digital workflow. Thus, it is important to have knowledge about production accuracy and tolerances. This study presents a method to test additive manufacturing units for accuracy and repeatability. (C) 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved
Wiberg, Anton, Persson, Johan, Ölvander, Johan, Linköpings universitet, Institutionen för ekonomisk och industriell utveckling, Maskinkonstruktion, and Linköpings universitet, Tekniska fakulteten
Rapid prototyping journal. 25(6):1080-1094
Engineering and Technology, Mechanical Engineering, Teknik och teknologier, Maskinteknik, Additive manufacturing, Design automation, Design for additive manufacturing, Design optimization, and Knowledge-based engineering
PurposeThis paper aims to review recent research in design for additive manufacturing (DfAM), including additive manufacturing (AM) terminology, trends, methods, classification of DfAM methods and software. The focus is on the design engineer’s role in the DfAM process and includes which design methods and tools exist to aid the design process. This includes methods, guidelines and software to achieve design optimization and in further steps to increase the level of design automation for metal AM techniques. The research has a special interest in structural optimization and the coupling between topology optimization and AM.Design/methodology/approachThe method used in the review consists of six rounds in which literature was sequentially collected, sorted and removed. Full presentation of the method used could be found in the paper.FindingsExisting DfAM research has been divided into three main groups – component, part and process design – and based on the review of existing DfAM methods, a proposal for a DfAM process has been compiled. Design support suitable for use by design engineers is linked to each step in the compiled DfAM process. Finally, the review suggests a possible new DfAM process that allows a higher degree of design automation than today’s process. Furthermore, research areas that need to be further developed to achieve this framework are pointed out.Originality/valueThe review maps existing research in design for additive manufacturing and compiles a proposed design method. For each step in the proposed method, existing methods and software are coupled. This type of overall methodology with connecting methods and software did not exist before. The work also contributes with a discussion regarding future design process and automation.