The use of computers in manufacturing has enabled the development of several new sheet metal forming processes, which are based upon older technologies. This paper describes modifications that have ...been made to traditional forming methods such as conventional spinning and shear forming, forming processes in which deformation is localized. Recent advances have enabled this localized deformation to be accurately controlled and studied. Current developments have been focused on forming asymmetric parts using CNC technology, without the need for costly dies. Asymmetric Incremental Sheet Forming has the potential to revolutionize sheet metal forming, making it accessible to all levels of manufacturing. This paper describes the genesis and current state-of-the-art of Asymmetric Incremental Sheet Forming.
Abstract The combined potential of hydrogels and rapid prototyping technologies has been an exciting route in developing tissue engineering scaffolds for the past decade. Hydrogels represent to be an ...interesting starting material for soft, and lately also for hard tissue regeneration. Their application enables the encapsulation of cells and therefore an increase of the seeding efficiency of the fabricated structures. Rapid prototyping techniques on the other hand, have become an elegant tool for the production of scaffolds with the purpose of cell seeding and/or cell encapsulation. By means of rapid prototyping, one can design a fully interconnected 3-dimensional structure with pre-determined dimensions and porosity. Despite this benefit, some of the rapid prototyping techniques are not or less suitable for the generation of hydrogel scaffolds. In this review, we therefore give an overview on the different rapid prototyping techniques suitable for the processing of hydrogel materials. A primary distinction will be made between (i) laser-based, (ii) nozzle-based, and (iii) printer-based systems. Special attention will be addressed to current trends and limitations regarding the respective techniques. Each of these techniques will be further discussed in terms of the different hydrogel materials used so far. One major drawback when working with hydrogels is the lack of mechanical strength. Therefore, maintaining and improving the mechanical integrity of the processed scaffolds has become a key issue regarding 3-dimensional hydrogel structures. This limitation can either be overcome during or after processing the scaffolds, depending on the applied technology and materials.
The use of additive manufacturing technologies in different industries has increased substantially during the past years. Henry Ford introduced the moving assembly line that enabled mass production ...of identical products in the 20th century. Currently, additive manufacturing enables and facilitates production of moderate to mass quantities of products that can be customized individually. Additive manufacturing technologies are opening new opportunities in terms of production paradigm and manufacturing possibilities. Manufacturing lead times will be reduced substantially, new designs will have shorter time to market, and customer demand will be met more quickly. This article identifies additive manufacturing implementation challenges, highlights its evolving technologies and trends and their impact on the world of tomorrow, discusses its advantages over traditional manufacturing, explores its impact on the supply chain, and investigates its transformative potential and impact on various industry segments.
Additive manufacturing of complex volumetric structures opened new frontiers in many technological fields, turning previously inconceivable designs into a practical reality. Electromagnetic ...components, including antenna and waveguiding elements, can benefit from exploring the third dimension. While fused deposition modeling (FDM) polymer printers become widely accessible, they manufacture structures with moderately low electromagnetic permittivities, compared to metals. However, metal 3D printers, being capable of producing complex volumetric constructions, remain extremely expensive and hard to maintain apparatus, suitable for high-end market applications. Here we develop a new metal printing technique, based on a low-cost and simple FDM device and subsequent electrochemical deposition. For testing the new method, we fabricated several antenna devices and compared their performances to standard printed FeCl
etched board-based counterparts, demonstrating clear advantages of the new technique. Our new metal printing can be applied to manufacture electromagnetic devices as well as metallic structures for other applications.
Metal Additive Manufacturing (AM) processes, such as selective laser melting (SLM), enable the fabrication of arbitrary 3D-structures with unprecedented degrees of freedom. Research is rapidly ...progressing in this field, with promising results opening up a range of possible applications across both scientific and industrial sectors. Many sectors are now benefiting from fabricating complex structures using AM technologies to achieve the objectives of light-weighting, increased functionality, and part number reduction, among others. AM also lends potential in fulfilling demands for reducing the cost and design-to-manufacture time. Aluminium alloys are of the main material systems receiving attention in SLM research, being favoured in many high-value applications. However, processing them is challenging due to the difficulties associated with laser-melting aluminium where parts suffer various defects. A number of studies in recent years have developed approaches to remedy them and reported successful SLM of various Al-alloys and have gone on to explore its potential application in advanced componentry. This paper reports on recent advancements in this area and highlights some key topics requiring attention for further progression. It aims to develop a comprehensive understanding of the interrelation between the various aspects of the subject, as this is essential to demonstrate credibility for industrial needs.
Abstract Background With rapid emergence of 3D printing technology, surgeons have recently started to apply this for nearly all areas of orthopaedic trauma surgery. Computed tomography or magnetic ...resonance images of trauma patients can be utilized for making graspable objects from 3D reconstructed images. Patient specific anatomical models can thereby be created. They enhance surgeon's knowledge of their patients' precise patho-anatomy, regarding both traumatized bones and soft tissue as well as normal areas, and therefore help in accurate preoperative planning. 3D printed patient specific instrumentation can help to achieve precise implant placement, and better surgical results. Most importantly, customized implants, casts, orthoses and prosthetics can be manufactured to match an individual's anatomy. Three dimensional (3D) printing, also called as ‘additive manufacturing’ and ‘rapid prototyping’ is considered as the “second industrial revolution”, and this appears to be especially true for orthopaedic trauma surgery. Methods A literature search was performed for extracting all papers related to 3D Printing applications in orthopaedics and allied sciences on the Pubmed, and SCOPUS; using suitable key terms and Boolean operators (“3D Printing” OR “3 dimensional printing” OR “3D printed” OR “additive manufacturing” OR “rapid prototyping”) AND (‘‘Orthopaedics” OR “Orthopaedics’’) AND (“Trauma” OR “Injury”)in June 2018. Search was also performed in Web of Science, Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews. No limits were set on the time period or evidence level, as 3D printing in orthopaedics is relatively recent and mainly low level evidence is available. Titles and abstracts were screened and all duplicate and unrelated papers were excluded. Papers related to orthopaedic trauma were manually selected for this review. Results The search on Pubmed retrieved 144 Papers and similar search on SCOPUS retrieved 94 papers. Additional searches did not reveal more relevant papers. After excluding duplicates and unrelated papers, and on screening of titles and abstracts, 59 papers were considered for review. Papers related to spine fractures only were not included, as they have been covered in another paper in this journal issue. Conclusion All over the world, orthopaedic Surgeon's and allied professionals and scientists are enthusiastically using 3D printing technology for designing patient specific models, instrumentation, implants, orthosis and prosthesis, besides 3D bioprinting of bone and cartilage scaffolding, and the same has been applied for nearly all areas of orthopaedic trauma surgery, from head to foot.
Abstract
Additive manufacturing (AM) implementation has advanced beyond prototyping towards becoming an extremely configurable manufacturing process with the illustrated ability to change ...conventional manufacturing in the future generations entirely. AM is completely based on Rapid Prototyping (RP), which helps fabricate critical and immense structure with 3D CAD software. The primary goal of this method is to create a product with optimal features such as compact, increased energy absorption, material reduction, insulation, and heat exchange. On the opposite, modeling and generating lattice structures and implementing different applications are all required. This review will get into the concepts of various classifications of additive manufacturing and its features.
Fused filament fabrication is considered one of the most used processes in additive manufacturing rapid prototypes out of polymeric material. Poor strength of the deposited layers is still one of the ...main critical problems in this process, which affects the mechanical properties of the final parts. To improve the mechanical strength, investigation into various process parameters must be considered. In this article, the influence of different process parameters has been experimentally investigated by means of physicochemical and mechanical characterizations. Special attention was given to the thermal aspect. In that respect, the in situ measurement of temperature profile during deposition indicated that several parameters affect the cooling rate of material and consequently have an influence on the final parts. It was found that the influence of increasing the extruder temperature is more significant in comparison with other process parameters.
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