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Abstract Fused deposition modeling (FMD) is considered one of the most common additive manufacturing methods for creating prototypes and small functional parts. Many researchers have studied Polylactic acid (PLA), Polycarbonate (PC), and Acrylonitrile butadiene styrene (ABS) as a material for fused deposition modeling printing. Among them, Polylactic Acid (PLA) is considered one of the most popular thermoplastic materials due to its low cost and biodegradable properties. In this study, silk PLA material was used. In Fused deposition modeling (FMD), the selection of printing parameters plays a pivotal role in determining the overall quality and integrity of the 3D-printed products. These parameters significantly influence the quality and strength of 3-D printed products. This study investigates the mechanical properties of silk-PLA printed specimens under different printing conditions, such as layer thickness, nozzle temperature, and print speed. All the tensile specimens were tested using ASTM D638 to characterize Young’s modulus and ultimate tensile strength. The thickness of the layers of tensile specimens was set to 0.1 mm, 0.15 mm, and 0.2 mm. The temperatures of the nozzle used during printing varied from 200°C, 210°C, and 220°C, whereas print speeds of 100 mm/s, 120 mm/s, and 140 mm/s were considered. The other printing parameters were kept consistent for all specimens. The result indicates tensile strength generally increases with increasing temperature of the nozzle, up to 220°C; however, a decline was observed in the average Young’s modulus value when the thickness of the layer increased from 0.10 mm to 0.20 mm. According to the results of the ANOVA analysis, the interaction between layer thickness, nozzle temperature, and printing speed significantly affects the tensile strength and Young’s modulus of Silk-PLA. This study reveals that nozzle temperature is the most critical parameter regarding the ultimate tensile strength and Young’s modulus, providing crucial insights for optimizing 3D printing parameters. 

The mechanical properties of woven jute fiber-reinforced PLA polymer laminates additively manufactured through Laminated Object Manufacturing (LOM) technology are simulated using the finite element method in this work. Woven jute fiber reinforcements are used to strengthen bio-thermoplastic PLA polymers in creating highly biodegradable composite structures that can serve as one of the environmentally friendly alternatives for synthetic composites. A LOM 3D printer prototype was designed and built by the authors. All woven jute/PLA biocomposite laminated specimens made using the built prototype in this study had their tensile and flexural properties measured using ASTM test standards. These laminated structures were modeled using the ANSYS Mechanical Composite PrepPost (ACP) module, and then both testing processes were simulated using the experimentally measured input values. The FEA simulation results indicated a close match with experimental results, with a maximum difference of 9.18%. This study served as an exemplary case study using the FEA method to predict the mechanical behaviors of biocomposite laminate materials made through a novel manufacturing process. 

This Work-in-progress paper presents the pilot study of implementing a Virtual Reality (VR) environment to teach a junior-level Mechanical Engineering laboratory class at Prairie View A&M University. The target class is the manufacturing processes laboratory, which initially aimed to provide a hands-on experience with various manufacturing equipment. Providing students with systematic training followed by repetitive access to manufacturing equipment is required for longer knowledge retention and safety in laboratories. Yet, complications from the pandemic and other logistical events have negatively affected many universities' laboratory courses. The objective of this study is to examine the potential and effectiveness of the VR framework in engineering education. More specifically, this paper details the project's first phase, which includes the development and deployment of machining VR modules and preliminary outcomes. The VR module in this phase is based on the existing hammer fabrication project that requires the utilization of a milling machine, drill press, lathe, tap, and threading dies. A virtual replica of the machining laboratory was created using C# and the unity 3D game engine and published as an Android Package Kit (APK) for the META platform to be used in Oculus Quest 2 devices. The module is composed of three submodules, each corresponding to different hammer parts. These VR submodules replace traditional verbal and video training and are deployed in two semesters with 46 student participants. The student performance in project reports is compared with a control group for a quantitative assessment. Early conclusions indicate that the students remember the operation procedures and functions of equipment longer and are more confident in operating each manufacturing equipment leading to better quality parts and reports. 

Purpose This paper aims to summarize the up-to-date research performed on combinations of various biofibers and resin systems used in different three-dimensional (3D) printing technologies, including powder-based, material extrusion, solid-sheet and liquid-based systems. Detailed information about each process, including materials used and process design, are described, with the resultant products’ mechanical properties compared with those of 3D-printed parts produced from pure resin or different material combinations. In most processes introduced in this paper, biofibers are beneficial in improving the mechanical properties of 3D-printed parts and the biodegradability of the parts made using these green materials is also greatly improved. However, research on 3D printing of biofiber-reinforced composites is still far from complete, and there are still many further studies and research areas that could be explored in the future. Design/methodology/approach The paper starts with an overview of the current scenario of the composite manufacturing industry and then the problems of advanced composite materials are pointed out, followed by an introduction of biocomposites. The main body of the paper covers literature reviews of recently emerged 3D printing technologies that were applied to biofiber-reinforced composite materials. This part is classified into subsections based on the form of the starting materials used in the 3D printing process. A comprehensive conclusion is drawn at the end of the paper summarizing the findings by the authors. Findings Most of the biofiber-reinforced 3D-printed products exhibited improved mechanical properties than products printed using pure resin, indicating that biofibers are good replacements for synthetic ones. However, synthetic fibers are far from being completely replaced by biofibers due to several of their disadvantages including higher moisture absorbance, lower thermal stability and mechanical properties. Many studies are being performed to solve these problems, yet there are still some 3D printing technologies in which research concerning biofiber-reinforced composite parts is quite limited. This paper unveils potential research directions that would further develop 3D printing in a sustainable manner. Originality/value This paper is a summary of attempts to use biofibers as reinforcements together with different resin systems as the starting material for 3D printing processes, and most of the currently available 3D printing techniques are included herein. All of these attempts are solutions to some principal problems with current 3D printing processes such as the limit in the variety of materials and the poor mechanical performance of 3D printed parts. Various types of biofibers are involved in these studies. This paper unveils potential research directions that would further widen the use of biofibers in 3D printing in a sustainable manner.