Review on Additive Manufacturing of Multi-Material Parts:Progress and Challenges

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

*WINNER* Investigation of the thermal properties of various short carbon fiber reinforced polymers in Fused Filament Fabrication process

A considerable amount of literature has been published on the thermal properties of the additively manufactured polymers. However, there has been no study focused on the effect of the reinforced fiber in various matrix materials to measure the thermal properties of such additively manufactured parts. The aim of this research is to explore the influence of various matrix materials, numerically and experimentally, on the thermal conductivity, thermal strain and degree of healing in matrix materials of PETG, PC/PBT, ABS and Nylon. The anisotropic behavior of the composites is also evaluated by changing the build direction. This work also attempts to simulate the temperature evolution in the printed materials. In order to do this, 3D implicit finite difference method is constructed using element activation method. The results obtained are important in reporting the relationship between short carbon fibers and different polymers. Our research group has reported valuable findings on continuous fiber reinforced additive manufacturing processes. The current findings of our group for the thermal properties of short carbon fiber reinforced filaments performed in this study will be benchmarked to differentiate the pros and cons of both technologies

J-tube Pull-In of Rigid Risers.

This work covers an advanced finite element analysis (FEA) approach of investigating riser pull-in through an existing J-tube up to an offshore platform. A riser is a vertically oriented piping used to deliver fluid, gas or other relevant packages upward. The challenges of this process consists of several bending segments along the J-tube, multiple contact issues in conjunction with pull-in of the riser, the modeling of the large geometry of the arrangement as well as the complex friction mechanics. The main focus of this project is on incorporating above mentioned details in the software programs ANSYS and SIMLA. The numerical model includes a rigid riser, J-tube with fixed supports, seabed, pull-in wire and vessel back-tension; in order to compare the suitability for pull-in analyses of the two programs. This work includes evaluation of important design criteria such as maximum pull-in force, plastic strain and stresses along the riser, analytical calculations as well as comparing the outcome between all of the obtained results. The results can be used to verify the capability of the pull-in winch for a platform

Influence of the Different Matrix Materials on the Thermal Properties of Short Carbon Fiber Reinforced Composites

A considerable amount of literature has been published on the thermal properties of the short carbon fiber reinforced composites (SCFRC). However, no study has focused on the effect of the various matrix materials on the thermal properties of the SCFRC. The aim of this study is to investigate the thermal propertiesof neat and composite PETG, PC/PBT, ABS, and Nylon filled with short carbon fibers. In order to do this, thermal conductivity and thermal diffusivity of the samples were measured. Thermogravimetric and differential scanning calorimetry analyses were performed to study degradation, glass transition temperature, and specific heat value. The findings of the study are essential in reporting the relationships between the SCFRCs and commonly used polymer materials.Mechanical Engineerin

Machine Learning-Based Investigation of the 3D Printer Cooling Effect on Print Quality in Fused Filament Fabrication: A Cybersecurity Perspective

Additive manufacturing (AM), also known as three-dimensional (3D) printing, is the process of building a solid object in a layer-wise manner. Cybersecurity is a prevalent issue that appears more and more frequently as AM becomes popular. This paper focuses on the effect of fan speed on the printing quality and presents a plugin called Fan Speed Attack Detection (FSAD) that predicts and monitors fan speeds throughout the printing process. The goal of the plugin is to prevent cybersecurity attacks, specifically targeting fan speed. Using the proposed FSAD, any fan speed changes during the printing process are evaluated to see whether the printer can sustain the abnormal fan speed change and still maintain good print quality