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In this chapter, the current state and future trends in smart manufacturing (SM) and its technologies are presented with the perspective of economic growth and evolution of policies and strategies that steer its growth. The long-term effect of the COVID-19 pandemic on manufacturing is investigated. As a result of the COVID-19 pandemic, a long-lasting effect on manufacturing is foreseen, particularly in the supply chain dependency. To overcome future supply chain disruptions, attention is expected to shift towards incorporating industrial and service robotics, additive manufacturing, and augmented and virtual reality. Additive manufacturing will continue to play an increased role in customized product manufacturing. More demand is expected in the long term of additive manufacturing to counter future supply chain interruption.

The objective of this paper is to present the modeling approach for homogenizing the 3D-printed composite parts for the accurate prediction of effective mechanical properties. The Mori–Tanaka (MT) approach associated with two-step homogenization is applied to partially oriented short carbon fiber (SCF)-reinforced polycarbonate (SCF/PC)-based composites and compared with the experimental results. Detailed microstructural analysis was performed to investigate the variation in fiber length and bead dimensions that occurred due to change in fiber percentage (3%, 5%, 7.5%, and 10% by vol.). A two-step homogenization framework was performed in this research. Change in fiber length was considered in the first-step homogenization and change in bead dimensions was considered in the second step of homogenization approach to find the microscale and mesoscale constitutive properties of SCF/PC 3D-printed composite samples using the MT method respectively. Results of this study revealed that the stiffness of the composite samples increases with the increase in fiber percentage. As we increase the SCF, significant variations were observed in the fiber length and bead dimensions which also significantly affect the mechanical properties of 3D-printed composite parts. Results obtained after considering the fiber length and bead dimensions in mathematical calculation helps in reducing the error gap between the homogenized numerical and experimental results. It was also concluded that the prediction of Young’s modulus using higher fiber percentage has relatively low errors. Eventually, the properties attained from the respective approach help to find out the macro fields (average stress and average strain) in the 3D-printed composite samples.

Mechanical properties of fiber reinforced additive manufacturing (FRAM) parts are affected by the fiber size and orientation. Oriented fiber composite is most likely to produce better properties. The objective of this research is to perform a comparative analysis of the mechanical properties of short and continuous fiber reinforced nylon 6 produced with fused filament fabrication (FFF) technology. In this study, it was observed that tensile, compression and flexural properties are significantly affected by the change in the fiber length and orientation. Scanning electron microscopy (SEM) was performed after mechanical testing to observe the influence of fiber on the final properties. From the testing, it was observed that continuous-FRAM (C-FRAM) parts show better properties in tensile loading and short-FRAM (S-FRAM) in bending. S-FRAM parts show better improvement in flexural and compression properties as compared to CFRAM parts. Morphological analysis of tested 3D-printed parts concluded that the fiber-pull out and fiber breakage are the main failure mechanisms.

One of the biggest challenges to 3D printing is that typical desktop printers are stationary with a limited workspace. A mobile 3D-printing platform, which has omnidirectional wheels that allow for unrestricted movement along x- and y-axes, can alleviate that restriction. The research team in this project performed a series of preliminary material tests with such a fully constructed platform. The system was tested with materials from three different industries that could benefit from mobile additive manufacturing technology. A cement paste was tested for the construction industry, frosting for the food industry, and clay paste for the fine arts industry. Next, a statistical experimental analysis was performed to determine the optimum printing parameters to obtain geometrical accuracy of the object being printed. The independent variables chosen for the material and the printing platform included the material type, percent concentration of dry material to wetting agent, layer height, layer width, and printing speed. Multiple samples were printed for each combination of independent variables. The dependent variables, maximum taper angle and x-y-z measurements, were then found from the printed samples. Principal Component Analysis was performed on the taper angle and x-y-z measurements to create a single index which represented the error in print quality. A slightly modified 2 k factorial design was then used to determine which printing parameters and material type significantly affected the error index. Finally, response surface methodology along with the method of steepest ascent was used to identify the optimum printing parameters.

In this research study, the design and fabrication workflow of functionally graded materials (FGMs) were introduced using fused filament fabrication (FFF) process. Rigid polymers were mechanically characterized in three printing directions. Tensile strength and modulus of elasticity values for YZ and XY printing orientation specimens indicated similar results. Printing in the XZ direction showed poor strength values in comparison with other printing directions. Interface analysis with different transition patterns was accomplished and the advantage of gradient transition was achieved. Micrography of specimens was analyzed to investigate the internal structure and was used to validate the test results. Statistical methods were applied to investigate the relationship between microstructural descriptors (volume fractions) and process-related parameters (printing temperatures). The results of the analysis of variance (ANOVA) have confirmed that printing temperature and concentration have a significant impact on tensile test results. The data-driven approach was employed to construct a linear regression models in order to formulate input data for finite element analysis (FEA). As a result of FEA simulation, effective Young’s modulus was calculated using a MATLAB code. FEA-predicted Young’s moduli were validated through experimental test results. The comparison of the numerical method and experimental values showed less than 5% error for FGM specimens printed in 250, 260 and 270 °C temperatures. FFF process with FGM could have potential applications in medical, structural, and automotive industries by locally varying material properties. This study presents a unique method of fabricating FGM structures with low-cost manufacturing process.

Additive manufacturing (AM) technologies provide a method of fabrication that minimizes the production of waste and maximizes part customization. The most common form of this technology is material extrusion (ME) in which material is deposited layer-by-layer to produce a highly customized part. However, this additive production method has experienced difficulty in widespread adoption in metal fabrication due to the inability to produce metallic parts with strong mechanical properties. This study presents some innovations on a new metal-fabrication technique for ME printing that allows for low-cost metal printing. A metal powder polymer composite filament, with a high metal composition, can be printed and sintered to yield a part that is completely metal. Overall, this study provides the initial investigation of the microstructural behavior and the resulting hardness levels. This study found that the metal powder in finished parts is fused by approximately 90% derived from the percent area porosity on a microstructural level. The final hardness of the processed parts is reduced by approximately 60%. Characterizing these properties is the initial step in incorporating ME technology in the field of metal 3D printing.

The objective of this research is to perform the processing and mechanical characterization on 3D-printed high-temperature polymer (polycarbonate) reinforced with short carbon fiber (SCF) composite material fabricated with the help of fused filament fabrication process. For this study, different SCF volume fractions (3%, 5%, 7.5%, 10%) with varying printing speed (25, 50, 75 mm/s) are taken as the input variables. It was observed that tensile, flexural, compressive properties and micro-hardness were greatly affected by varying the input processing parameters. To find the orthotropic properties of 3D-printed specimens, tensile properties are analyzed on 0° in the X-Y plane, 90° in the X-Y plane, and 90° in Z-axis. Scanning electron microscopy (SEM) is performed to study the effect of fiber breakage, fiber distribution, fiber accumulation, and fiber length on the mechanical performance of the final part. After performing mechanical testing, investigation of microstructural behavior of tensile, flexural, and compressive samples is accomplished using SEM. From the micrograph analysis and mechanical testing, it was noticed that fiber behavior inside the composite has created a great influence in deciding the mechanical performance of the final part. Micromechanics and classical lamination theory phenomena are followed to determine the effective young’s modulus of 3D-printed samples mathematically. Printing direction and reinforcement percentage are found out to be the most influential parameters in deciding the final properties of 3D-printed specimens by using the statistical tool ANOVA. Response surface methodology is used to determine the optimum parameters to get good-quality print with SCF-reinforced PC.

Additive manufacturing (AM) is a widely used layer-by-layer manufacturing process. Material extrusion (ME) is one of the most popular AM techniques. Lately, low-cost metal material extrusion (LCMME) technology is developed to perform metal ME to produce metallic parts with the ME technology. This technique is used to fabricate metallic parts after sintering the metal infused additively manufactured parts. Both AM and sintering process parameters will affect the quality of the final parts. It is evident that the sintered parts do not have the same mechanical properties as the pure metal parts fabricated by the traditional manufacturing processes. In this research, several machine learning algorithms are used to predict the size of the internal voids of the final parts based on the collected data. Additionally, the results show that the neural network (NN) is more accurate than the support vector regression (SVR) on prediction.

Hirel, Catherine/0000-0002-6297-5650; LUNEAU, Dominique/0000-0002-1831-7693 Tetraphenylporphyrin derivatives a synthetic heterocycles with convenient preparation and a richness of properties which make them attractive in broad fields such as energy, life and materials sciences. Thus, in the quest for new radical architectures, tetraphenylporphyrins are prime candidates. To this end, we designed free-base tetraphenylporphyrins bearing nitronyl and imino nitroxide moieties covalently bonded to the para-position of the meso-phenyl substituent. Their detailed synthesis and characterization arc reported here. Scientific and Technological Research Council of Turkey-TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [113Z005] Financial support from the Scientific and Technological Research Council of Turkey-TUBITAK (project 113Z005) is gratefully acknowledged. The authors declare no competing financial interest.

The syntheses of 4-[4-(4,4,5,5-tetramethyl-2-imidazoline-3-oxide-1-oxyl-2-yl)phenoxy]phthalonitrile (3, C21H19N4O3) and 4-[4-(4,4,5,5-tetramethyl-2-imidazoline-1-oxyl-2-yl)phenoxy]phthalonitrile (4) were carried out by microwave-assisted nucleophilic aromatic substitution of 4-nitrophthalonitrile (2) by the pre-formed 2-(4-hydroxyphenyl)-4,4,5,5-tetramethyl-2-imidazoline-3-oxide-1-oxyl (1). Compounds 3 and 4 were characterized unambiguously by a rich array of analyses, such as melting point, FT–IR, MALDI–TOF MS, elemental analysis, UV–Vis, CV, EPR, magnetic measurements and single-crystal X-ray diffraction. Structural studies demonstrate that the C—H...X and C—X...π (X = O and N) interactions in the radical nitronyl nitroxide groups play an important role in the assembly of the crystal structures. Moreover, cyclic voltammetry analyses show that the phthalonitrile substituent retains the redox properties of the Ullman radicals.

Innovations in engineering education are undergoing a noticeable transformation. Higher education institutions are practicing distance education, remote laboratories, studio pedagogies and several other approaches in order to increase their students’ retention, success, and preparedness for the job market. In engineering education, maker spaces have become popular in the last ten years in universities as well as community colleges, high-schools and community innovation hubs. A large number of engineering colleges have allocated significant spaces, and at some universities entire buildings as maker spaces to be used for curricular and extracurricular activities. Success stories of these types of spaces are well documented. This paper describes the activities and programs held at Tennessee Tech University’s maker space called ‘iMakerSpace.’ These accomplishments include several workforce development activities. The impact and effectiveness of the iMakerSpace is evaluated through analysis of survey data.

İnsan can ve mal güvenliğinin sağlandığı, her türlü tehlikeden uzak ve huzurlu bir ortamda yaşama arzusu içindedir. Bu noktada güvenliğin sağlanması, önemli bir olgu olarak karşımıza çıkmaktadır. Güvenliği sağlamak, bireyin güvenliğinden, küresel güvenliğe kadar çok geniş bir alanı içerisine almaktadır. Fakat genişlik ne olursa olsun başlangıç birey ve toplum güvenliği olarak gelişmektedir. Toplumun huzur ve sükûnu devlet içerisinde teşkilatlanmış birimlerce sağlanmaktadır. Bu bağlamda teşkilatlandırılmış genel kolluğa yardımcı kolluk olarak değerlendirilmesi gereken köy ve güvenlik koruculuğu sistemi kamu düzeninin ve güvenliğinin sağlanmasında önemli bir aktör olarak karşımıza çıkmaktadır. Bu çalışmada öncelikle güvenlik korucularının görev ve yetkileri göz önüne alınarak, gelinen son durumları yasal zeminde ele alınmaktadır. Devamında ise köy koruculuğu, güvenlik koruculuğu ve gönüllü güvenlik koruculuğunun hâlihazırdaki durumu irdelenerek kamu görevi ve sürekliliği bağlamında öneriler sunulmaktadır.