Metallic additive manufacturing: state-of-the-art review and prospects

Abstract

Additive manufacturing processes, used for more than 25 years, are no longer confined to rapid prototyping applications. Mostly used nowadays in niche markets (medical applications, aerospace. . . ) to manufacture metallic parts, they should provide improvements in terms of time-to-market, ecological impact and design compared to traditional industrial processes. Current metallic additive manufacturing studied in this paper are Selective Laser Sintering, Direct Metal Laser Sintering, Selective Laser Melting, Electron Beam Melting and Direct Metal Deposition. The performances of these processes are investigated through criteria derived from the time cost quality triangle and some prospects concerning these processes are given.

Personalization in Design through New Technological Achievements

“…At the beginning, additive technologies were primarily used for creation of prototypes [5] and were known as rapid prototyping processes. Recent, important technological and material improvements enable these processes applicability for the creation of end-use products [6,7], consequently the name change into rapid manufacturing or additive manufacturing. This opens new possibilities for production of different and unique parts for a very short time.…”

“…The points are created directly in the Grasshopper, defined by the three-coordinated axis (X, Y and Z), in that way allowing their additional translation by the user. Translation of the points (3,5,7,9) along the X and Y axis is obtained by sliders, allowing the user easy manipulation as has been shown in previous studies [19]. There is no possibility to move the point along the z-axis for practical reasons.…”

Building without melting: a short review of friction-based additive manufacturing techniques

“…Though, Arcam-based electron beam melting (EBM) and EOS-based direct metal laser sintering systems (DMLS) (Vayre et al, 2012) have enabled pivotal breakthroughs in the field of AM, fabrication of high performance parts is limited due to solidification defects and undesirable interplay between multiple thermal cycles and evolving microstructure.…”

Design and additive manufacture for flow chemistry

“…153 When the build is complete the chamber is allowed to cool to ambient temperature, then the part is removed from the build chamber, cleaned and any undesired support structures are removed. 154 These structures are put into place to support any overhanging features of the build, and to prevent the collapse of the molten metal during the build process. They are made from the same metal powder as the build itself.…”

“…Parameters such as the size of the laser spot, laser power, hatch distance (the distance between consecutive scan lines), layer thickness scan pattern and the scanning velocity can be varied, allowing the inputted energy to be accurately controlled to facilitate more accurate builds. In general, parts are built at a rate of around 5-20 cm 3 /h, depending on individual build parameters, 154 with accuracies of +/-0.05 mm being achieved over smaller parts. Laser spot size variations between 0.3 and 0.7 mm did however dictate the minimum wall thickness achievable during our research.…”