Additive manufacturing has already been established as a highly versatile manufacturing technique with demonstrated potential to completely transform conventional manufacturing in the future. The objective of this paper is to review the latest progress and challenges associated with the fabrication of multi-material parts using additive manufacturing technologies. Various manufacturing processes and materials used to produce functional components were investigated and summarized. The latest applications of multi-material additive manufacturing (MMAM) in the automotive, aerospace, biomedical and dentistry fields were demonstrated. An investigation on the current challenges was also carried out to predict the future direction of MMAM processes. It was concluded that further research and development is needed in the design of multi-material interfaces, manufacturing processes and the material compatibility of MMAM parts.

This general review paper presents a condensed view of recent inventions in the Additive Manufacturing (AM) field. It outlines factors affecting the development and commercialization of inventions via research collaboration and discusses breakthroughs in materials and AM technologies and their integration with emerging technologies. The paper explores the impact of AM across various sectors, including the aerospace, automotive, healthcare, food, and construction industries, since the 1970s. It also addresses challenges and future directions, such as hybrid manufacturing and bio-printing, along with socio-economic and environmental implications. This collaborative study provides a concise understanding of the latest inventions in AM, offering valuable insights for researchers, practitioners, and decision makers in diverse industries and institutions.

This paper thoroughly examines the advancements and challenges in the field of additively manufactured Functionally Graded Materials (FGMs). It delves into conceptual approaches for FGM design, various manufacturing techniques, and the materials employed in their fabrication using additive manufacturing (AM) technologies. This paper explores the applications of FGMs in diverse fields, including structural engineering, automotive, biomedical engineering, soft robotics, electronics, 4D printing, and metamaterials. Critical issues and challenges associated with FGMs are meticulously analyzed, addressing concerns related to production and performance. Moreover, this paper forecasts future trends in FGM development, highlighting potential impacts on diverse industries. The concluding section summarizes key findings, emphasizing the significance of FGMs in the context of AM technologies. This review provides valuable insights to researchers, practitioners, and stakeholders, enhancing their understanding of FGMs and their role in the evolving landscape of AM.

Fused Filament Fabrication (FFF) is a promising technology for production of fiber-reinforced composite parts with complex geometries. Continuous Fiber Reinforced Additively Manufactured (CFRAM) parts are becoming more prominent due to their mechanical performance, light weight, and recyclability. CFRAM components are lighter, yet they are strong materials with a wide range of potential applications in the automotive industry, aerospace, medical tools, and sports goods. The wide range of applications of these novel materials justifies the need to study their properties. Tensile is one of the most important tests to evaluate the mechanical performance of CFRAM parts. In this paper, a comprehensive study is conducted on tensile properties of CFRAM components. The composite parts are printed using a dual nozzle 3D printing machine and their tensile performance is investigated. Furthermore, the effect of fiber type, fiber content, infill density, infill pattern, and layer thickness on tensile properties was studied. Nylon was used as the matrix and Carbon fiber (CF), fiberglass (FG), and Kevlar were used as reinforcing agents. Microstructural analysis was conducted to investigate the fracture mechanism, internal morphology, interlayer adhesion, and the printing quality of specimens. Finally, a comparative study is conducted on the price and printing time of CFRAM parts. It is observed that fiber inclusion increases the tensile strength up to 2200%; moreover, increasing the fiber content improves the tensile performance of composite. The results obtained demonstrate that CF-reinforced parts have better performance compared to FG and Kevlar-reinforced components. The results show that CFRAM parts have potential to replace metals and conventional composites for engineering applications like the automobile industry.