materials Review Applications of Additively Manufactured Tools in Abrasive Machining—A Literature Review Mariusz Deja 1,* , Dawid Zieli ´nski 1 , Aini Zuhra Abdul Kadir 2 and Siti Nur Humaira 2 1 Department of Manufacturing and Production Engineering, Faculty of Mechanical Engineering and Ship Technology, Institute of Machine and Materials Technology, Gda´nskUniversity of Technology, G. Narutowicza Str. 11/12, 80-233 Gda´nsk,Poland; [email protected] 2 School of Mechanical Engineering, Faculty of Engineering, Universiti Teknologi Malaysia, Skudai 81310, Johor Bahru, Malaysia; [email protected] (A.Z.A.K.); [email protected] (S.N.H.) * Correspondence: [email protected] Abstract: High requirements imposed by the competitive industrial environment determine the development directions of applied manufacturing methods. 3D printing technology, also known as additive manufacturing (AM), currently being one of the most dynamically developing production methods, is increasingly used in many different areas of industry. Nowadays, apart from the possibil- ity of making prototypes of future products, AM is also used to produce fully functional machine parts, which is known as Rapid Manufacturing and also Rapid Tooling. Rapid Manufacturing refers to the ability of the software automation to rapidly accelerate the manufacturing process, while Rapid Tooling means that a tool is involved in order to accelerate the process. Abrasive processes are widely used in many industries, especially for machining hard and brittle materials such as advanced ceramics. This paper presents a review on advances and trends in contemporary abrasive machining related to the application of innovative 3D printed abrasive tools. Examples of abrasive tools made Citation: Deja, M.; Zieli´nski,D.; with the use of currently leading AM methods and their impact on the obtained machining results Kadir, A.Z.A.; Humaira, S.N. were indicated. The analyzed research works indicate the great potential and usefulness of the new Applications of Additively constructions of the abrasive tools made by incremental technologies. Furthermore, the potential Manufactured Tools in Abrasive and limitations of currently used 3D printed abrasive tools, as well as the directions of their further Machining—A Literature Review. development are indicated. Materials 2021, 14, 1318. https:// doi.org/10.3390/ma14051318 Keywords: additive manufacturing; abrasive processes; abrasive tools; rapid prototyping; rapid tooling Academic Editor: Stanislaw Legutko Received: 8 January 2021 Accepted: 5 March 2021 1. Introduction Published: 9 March 2021 Nowadays, the proper selection of an appropriate manufacturing method, machine Publisher’s Note: MDPI stays neutral tools and tools is one of the most crucial decisions in the product development cycle [1,2]. with regard to jurisdictional claims in Additive manufacturing (AM) systems can be defined as a new generation of Flexible published maps and institutional affil- Manufacturing Systems (FMS) in which a variety of different products with different iations. materials can be flexibly produced using the same machines [3]. The unquestionable advantages of additive techniques, related, among other things, to the possibility of having design freedom allowing complex shapes to be produced, improving the mechanical strength properties of the products, and shortening the lead times, still come with a limited number of available materials and the necessity of post-processing to improve the surface Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. finish and dimensional accuracy. Nevertheless, advanced materials, including composite This article is an open access article materials with reinforcement phases, can be used for making composite and complex distributed under the terms and products working under heavy-duty operating conditions. Other than that, composite conditions of the Creative Commons materials can also be used to improve the dimensional accuracy of the printed parts. In Attribution (CC BY) license (https:// a study by Deja et al. [4], the Analytic Hierarchy Process (AHP) technique was used creativecommons.org/licenses/by/ as a decisive support method to compare a standard subtractive method with additive 4.0/). manufacturing for the fabrication of offshore machinery components. The obtained results Materials 2021, 14, 1318. https://doi.org/10.3390/ma14051318 https://www.mdpi.com/journal/materials Materials 2021, 14, x FOR PEER REVIEW 2 of 23 Materials 2021, 14, 1318 used as a decisive support method to compare a standard subtractive method2 of 22with addi- tive manufacturing for the fabrication of offshore machinery components. The obtained results showed that under specific technical requirements and production resources, CNC showed thatmilling under proved specific to be technical the most requirements appropriate andmethod production for the resources,fabrication CNC of the milling analyzed part. proved toThis be thecould most also appropriate be the case methodin current for industrial the fabrication practice of, where the analyzed other types part. of This mechanical could alsocomponents be the case and in tools current are industrialproduced practice,using subtractive where other techniques. types of However, mechanical in the near componentsfuture, and in tools the areface produced of the intensive using subtractive development techniques. of additive However, technologies, in the near 3D printing future, inmight the face gain of thean advantage intensive development over subtractive of additive technologies, technologies, even for 3D printingcomplex mightabrasive tools gain an advantagemade of advanced over subtractive materials technologies, and composites. even Figure for complex 1a,b show abrasive the comparison tools made between of advancedthe subtractive materials andtechnique composites. and additive Figure 1manufacturinga,b show the comparison technique, respectively, between the and they subtractivediffer technique as follows: and additive manufacturing technique, respectively, and they differ as follows:a. In AM, material is added layer by layer to build the desired solid 3D product, a. In AM, materialwhereas iswith added subtractive layer by layermethods, to build the thematerial desired is solidgradually 3D product, removed whereas from a solid with subtractiveblock to fabricate methods, the the final material parts. is gradually removed from a solid block to fabricateb. In the AM, final complex parts. shapes can be easily fabricated, whereas with subtractive methods, b. In AM,the complex process shapes has a can limited be easily ability fabricated, to produce whereas complex with shapes. subtractive methods, thec. process The AM has aprocess limited is ability mostly to suitable produce for complex materials shapes. that have low melting points such c. The AMas process polymers. is mostly Whereas suitable, with for subtractive materials thatmethods, have lowthe meltingprocess pointscan use such all solid as mate- polymers.rials Whereas,, irrespective with subtractiveof their melting methods, points. the process can use all solid materials, irrespectived. AM processes of their melting use raw points. material in forms of powder, filament or liquid; whereas, d. AM processeswith subtractive use raw materialmethods, in the forms raw material of powder, can filamentbe provided or liquid; as a solid whereas, block, forg- with subtractiveing or cast. methods, the raw material can be provided as a solid block, forging ore. cast. In AM, volumetric density and the weight of the constructive material of final com- e. In AM,ponent volumetric can be density controlled and during the weight operations, of the whereas constructive with materialsubtractive of method final s, it is componentassociated can be with controlled material during wastage operations, in the form whereas of chips. with subtractive methods, it isf. associatedThe AM with process material can be wastage applied in only the formto a selected of chips. range of materials, while subtrac- f. The AMtive process methods can be can applied handle only a wide to a selectedvariety of range materials. of materials, while subtractive methods can handle a wide variety of materials. (a) (b) Figure 1. FigureSchematic 1. Schematic diagrams diagrams of the subtractive of the subtractive manufacturing manufacturing process ( aprocess) and the (a) additive and the manu-additive manu- facturingfacturing process (b process). (b). In general,In general, subtractive subtractive processes processes generate generate more material more material waste compared waste compared to AM pro- to AM pro- cesses. Incesses. the past In fewthe past decades, few decades, AM has evolvedAM has evolved from functional from functional prototypes prototypes to exclusively to exclusively manufacturingmanufacturing various metallicvarious componentsmetallic components that cannot that be cannot produced be produced easily by easily other by sub- other sub- tractive manufacturingtractive manufacturing methods methods [5]. AM technologies[5]. AM technologies allow fabrication allow fabrication of partswith of parts high with high geometricgeometric complexity complexity and reduced and reduce post-processingd post-processing stages [6 ].stages Thermoplastic [6]. Thermoplastic polymers polymers remain the most popular class of additive manufacturing materials, but the number of metallic materials that are currently being used for metal printing is still increasing. These materials include