The advantage of Additive Manufacturing (AM) (e.g. reasonable time and expense in prototyping, and reliable product) has triggered the idea of using this method in Manufacturing of marine vessels components. The current article tries to introduce basic concepts of AM method and its application in marine industry; have a glance at Additive-manufactured parts microstructure; elaborate the challenges in investigation of mechanical properties of AM products; in order to makes this technology more known to domestic industry.

The swirler of the gas turbine combustion chamber is usually designed from nickel-based superalloys and produced by the conventional precision casting method under vacuum. The production of such parts is associated with high scrap due to geometrical complexity, high dimensional accuracy and also the use of ceramic cores. In recent decades, the use of the Additive Manufacturing process as a new and alternative method has been growing for the production of complex metal parts in the power plant industry. In this research, a gas turbine Swirler and several Inconel 625 samples were fabricated by SLM in optimal conditions of the main variables of the Manufacturing process such as laser power, scanning speed and the thickness of the melted layer. Microstructural studies were performed by optical Microscope on samples and some structural defects such as incomplete local melting, porosity, non-metallic oxide phases and Microcracks were identified. The printed swirler was compared with the computer model in all important and final Surfaces by non-contact dimensioning method. The surface quality and dimensional accuracy of the part were acceptable and it was evaluated within the tolerance range of the casting part. Also, hardness and tensile tests at ambient temperature were performed on the heat treated samples. The results showed that the values of the tensile properties of the printed samples were higher in the parameters of yield strength and ultimate strength, but lower in the parameter of relative elongation and the hardness was also the same.

The design and Manufacturing cubic porous scaffolds are a considerable notion in tissue engineering (TE). From Additive Manufacturing (AM) perspective, it has attained high appeal in the string of TE during the past decade. In the view of TE, the feasibili ty of Manufacturing intricate porous scaffolds with high accuracy contrast to prominent producing methods has caused AM the outstanding option for Manufacturing scaffold. From design perspective, porous scaffold structures play a crucial task in TE as scaf fold design with an adequate geometries provide a route to required strength and porosity. The target of this paper is achieve of best geometry to become an optimum mechanical strength and porosity of TE scaffolds. Hence, the cubic geometry has been chosen for scaffold and Cube, Cylinder and Hexagonal prism geometries have been selected for pore of structures. In addition, for noticing the porosity effects, pore size has been chosen in three size, and a whole of nine scaffolds have been designed. Designed s caffolds were generated using Fused Deposition Modeling (FDM) 3D Printer and dimensional specifications of scaffolds were evaluated by comparing the designed scaffolds with Scanning Electron Microscope (SEM). The samples were subjected to mechanical compre ssion test and the results were verified with th e Finite Element Analysis ( FEA). The results showed that f irstly, a s the porosity increases, the compressive strength and modulus of elasticity obviously decreased in all geometry pore scaffolds. Secondly, a s the geometry changes in similar porosity, cubic pore scaffold achieved higher compressive strength and modulus of elasticity than cylinder and hexagonal prime Experimental and FEM validated results proposed a privileged feasible pore geometry of cubic sc affold to be used in design and Manufacturing of TE scaffolds.

Additive Manufacturing in the modern world is progressing significantly, resulting in special applications in engineering sciences, medicine, and art. When the MIT university mixed the concept of time in the 3D printing process, time was considered as the fourth dimension. By combining the fourth dimension, the time, the smart materials made of Additive Manufacturing are able to a reaction to the external motivations (heat, voice, impact, etc) within a specified time. In the 4D printing process, the material configuration will be converted to a converter that will be exposed to external motivation such as heat, water, chemicals, electrical current and magnetic energy. It is expected that in the future, this technology will be widely used, requiring the application of various engineering disciplines, including mechanical engineering, in the fabrication and production of objects, because the overall perspective of the 4-D printing process is to make intelligent materials that are optimized using computational challenges and empirical knowledge. In this article, after reviewing the 3D printing and introducing smart materials, the issue of 4D printing has been investigated using this material. The mechanism, challenges, applications, and future of 4D printing has been discussed.

Additive Manufacturing comprises a set of methods enabling layer-by-layer fabrication of components using a three-dimensional model. Conversely, in subtractive Manufacturing, the process begins with a large volume of material and results in the final piece through material removal. One point of convergence between these two processes is the fabrication of machining tools (subtractive Manufacturing), such as milling cutters, turning inserts, and boring tools, through Additive Manufacturing, which can potentially catalyze significant advancements in various machining processes. This article explores several machining tool prototypes fabricated via Additive Manufacturing and discusses their advantages and capabilities. Additionally, some tools whose properties have been enhanced through Additive Manufacturing by altering their chemical composition are introduced, and the prospect of multi-material tool fabrication with varying hardnesses is deliberated. Investigations indicate that advancements in Additive Manufacturing processes can lead to the development of advanced tools capable of producing components with higher hardness and more complex geometries

For about three decades, researchers have been developing Additive Manufacturing Technology, or more generally, 3D printing technology. The technology of Additive Manufacturing or 3D printing can be considered as a result of the fourth industrial revolution in the early 21st century. The Fourth Industrial Revolution is known via concepts such as artificial intelligence, machine-human connectors, robotic technology and sensors, 3D printing technology, and cyber-physical sys tems, which combine real and virtual technologies to provide autonomy and communication between machines independent of humans. 3D printing is extensively applied in a number of industries, such as aerospace, automotive, medical and, dental components, alternative pieces for electronics, architectural models, and sports equipment. In addition, it is expanding in the fashion indus try. In this technology, firs t, the product is designed using 3D modeling software, then the parts are divided into horizontal layers based on the 3D design in the software. Then the data of the digital file is sent to the printer. After that, the product is made by placing the materials in successive layers on top of each other and each layer is fastened on top of each other with special adhesives or laser beam. This continues until the layers are completed and the final product is made. That is why the technology is called Additive Manufacturing. Materials used in 3D printing include glass, ceramics, metals, wax, sand, polymers and, resins. However, it is predicted that with the development of science in 3D printing materials, materials made of textile fibers will be introduced. For example, the TamiCare textile company has developed a 3D printing technology that aims to print fabrics using liquid polymers including natural latex, silicone, polyurethane, Teflon, and textile fibers including cotton, Rayon and, Polyamide. To convert a 2D design into a 3D product, 3D Cad software or programs such as Rhino are used. This software provides parametric design tools especially for designers who do not have coding experience. Parametric design tools are more efficient and easier to operate so that multiple changes to a design can be made with a single code. Based on the s tudies, it seems that the capabilities of 3D printing technology in the fashion indus try can help designers to create prototypes, produce the final product, as well as to produce customized products, and create an interactive experience between designers and audiences. The possibilities provided by 3D software to designers lead to more creativity, and designers can easily create what they have in mind by using 3D software. Applying CAD files also allows companies to quickly produce prototypes and create targeted products according to cus tomer needs. In addition, 3D printing can have a huge impact on the supply chain of traditional products such as fas t design process, less production time, reduced number of s tages required to produce the items, possibility of more dis tribution and decentralized production, reduced need for warehousing, packaging, and transportation. These are some of the things in the traditional process of production that can be influenced by technology. 3D printing helps businesses by reducing the amount of unused inventory and reducing capital loss. This technology has also contributed to the goals of sus tainable fashion, such as minimizing was te in printing, recycling materials as well as the use of environmentally friendly materials that will be highly regarded in the future of the indus try. In spite of these advantages, these products also have disadvantages, for example, designing with 3D CAD software, printers and various materials is a complex process that requires the cooperation of interdisciplinary knowledge and skills. In addition, it may be difficult for designers to unders tand the mathematical algorithms needed to produce accurate three-dimensional s tructures. Also, the high price of the final product, the low flexibility of the product in some 3D printing methods, the lack of finesse of the filaments compared to textile yarns can be considered as other disadvantages of the technology. Given that the use of 3D printing in the fashion indus try is an emerging topic for discussion, the research aims to answer the following ques tion: “ How is the 3D printing technology used in the fashion indus try? ” It seems that the capabilities of 3D printing technology can help designers to produce designs and customize the product with different materials and s tructures, and the possibilities that 3D software provides designers, make them more creative. It should also be noted that the environmental characteris tics of the technology have increased the importance of promoting knowledge about this topic. Thus, introducing and explaining 3D printing technology and understanding the advantages and disadvantages of the technology is important and necessary. In this paper, firs t, the 3D printing in the fashion indus try is introduced. Next, the 3D printing processes and the materials used in it are s tudied and examples of 3D printing technologies that are often used in the fashion indus try are introduced, which include five 3D printing Stereolithography methods, Selective Laser Sintering (SLS), Fused Deposition Modelling (FDM), PolyJet, Binder Jetting. Finally, 3D printing features will be examined to realize a part of sus tainable fashion. Since the paper considers the introduction and development of 3D printing technology in the fashion indus try, it can be called developmental research. But in terms of content, it is considered analytical research because after recognizing the different aspects of the subject and collecting the acquired information in different areas of Additive Manufacturing (3D) and the fashion indus try, the data have been analyzed and explained. In the research, the qualitative analysis method has been used to analyze the data and the method of data collection is documentary (library) and the data collection tool is note-taking sheets. The sampling method and the approximate volume of data are based on the available samples and are probably simple because among, the various methods using 3D printing, the five mos t widely used methods in the fashion indus try are analyzed and based on the results obtained from the data, the sus tainability aspects of 3D printing in fashion have been inves tigated. The s tudy aims to look at the future of the fashion indus try by using Additive Manufacturing Technology (3D printing) and identifying the ability of this technology to achieve the goals and concerns of the fashion indus try in the future. The results of the s tudy show that 3D printing has many benefits including the production of prototypes by designers, creating cus tomized products for consumers, improving the quality of products by designers, reducing the cos t of packaging, s torage, classification and, transportation; time management as well as the environmental properties of the technology, for example minimizing was te in printing, recycling materials and using environmentally friendly materials that will be highly regarded in the future of the indus try. However, there are s till challenges that designers face, i. e. the unavailability of 3D printing raw materials (filaments) to produce their products, the high cos t of the finished product if not combined with textiles; res trictions on mass production of 3D printing products, low flexibility compared to products made with textiles, res trictions on cutting and sewing, lack of variety in the color of the materials, limitation in coloring the materials, facing cutting challenges, removing and polishing supporting s tructures that need to be considered. It is predicted that when new materials are introduced to produce textile fibers, the quality of 3D printing fashion products will also improve and 3D printing materials can function as fabrics. 3D printing can also provide suitable solutions for the waste generated by fast fashion and test more environmentally friendly materials in the future.

In order to utilize NDT methods to evaluate manufactured parts via Additive Manufacturing (AM), scales are needed to represent probable defects in the produced part. In light of common defects in AM produced parts (gas porosity, powder porosity lack if fusion, etc. . . ) and difference in their forming mechanism with probable defects in parts manufactured via traditional means, using present calibration blocks are not very effective. In the presented paper herein, an innovative reference block with designated internal characteristics for the calibration of ultrasonic equipment has been designed and manufactured by SLM method. Then, it was tested by pulse-echo ultrasonic test method. To attain confidence in the precision and accuracy of designated characteristics, cutting of the part took place and their dimensions was measured by light microscope and their distance from free surface by micrometer. To obtain results indicated affirmation in dimensional accuracy and precision and hence their utilization as a reference block in BDT measurement was confirmed.

Despite of outstanding properties of cellular materials, their properties cannot be well controlled, and their applications are limited due to irregular pores. Although the use of cellular lattice structures repels this difficulty, complex geometry of these materials makes it impossible to produce metallic ones using conventional Manufacturing methods. In addition, Additively manufactured metallic samples are expensive. In this study, in order to fabricate and characterize inexpensive metallic cellular lattices, an indirect Additive Manufacturing process, including fused deposition modeling and gravity casting, is utilized and the effects of different parameters on the quality of the final part are assessed through experimental and numerical methods. Simulations’,results show that decreasing the melt load time, and increasing molten Al temperature, mold temperature, mesh height, and struts’,diameter increase the mold filling percentage. For the fabricated samples, the difference between the struts’,diameter of the sacrificial patterns and designed ones increases by decreasing the struts’,diameter, especially for horizontal struts. For metallic samples, the struts’,diameter’, s difference is mainly related to the sacrificial patterns so that the error arisen from casting process is just about 2. 2 percent. Also, using the utilized method, cellular lattices with struts’,diameter smaller than 3 mm cannot be fabricated. Microscopic images demonstrate that the samples’,defects are mainly of misrun type which are located on the top plate of BCC and BCCZ samples and on the horizontal struts of SC ones.