Over the last few years, fused filament fabrication (FFF) has become one of the most promising and widely used techniques for the rapid prototyping process. A number of studies have also shown the possibility of FFF being used for the fabrication of functional products, such as biomedical implants and automotive components. However, the poor mechanical properties possessed by FFF-processed products are considered one of the major shortcomings of this technique. Over the last decade, many researchers have attempted to improve the mechanical properties of FFF-processed products using several strategies—for instance, by applying the short fiber reinforcement (SFR), continuous fiber reinforcement (CFR), powder addition reinforcement (PAR), vibration-assisted FFF (VA-FFF) methods, as well as annealing. In this paper, the details of all these reinforcement techniques are reviewed. The abilities of each method in improving tensile, flexural, and compressive strength are discussed.

Pressure vessel is a container that has been used to contain a pressurized fluids, either oil, gas, or other chemical fluids. It is widely used for the oil, gas and other chemical based industries. Nowadays, finite element analysis is commonly used to reduce the high cost of testing a pressure vessel before manufacturing process. However, further validation is needed to ensure the results of the simulation and safety of the pressure vessels. In this study, theory of distortion energy is used as the tools of validation based on materials properties and behavior. And finally to ascertain wether the pressure vessel is possible for production or a refinement for safety is needed. The results of the study shown that theory of distortion energy can be used as validation tool for finite element analysis on a pressure vessels, however it cannot ensure the safety. Therefore other validation methods are needed to ascertain the safety of the pressure vessel discussed in this report. The cost analysis shown that failure theory combined with other calculation methods can save costs in pressure vessel testing, although some fairly expensive tests cannot be avoided.

There is a need to improve the mechanical properties and corrosion resistance by reducing the harmful lead content. Adding nickel as a solid solution strengthening element will improve the microstructure and reduce the corrosion rate. However, nickel's mechanism and solubility limits in the copper-zinc matrix are poorly understood. This study aimed to examine the effect of nickel addition of 1% to 4% on solid solution strengthening, microstructural modification, and increasing the corrosion resistance of recycled brass alloys. The methods used include preparing alloy samples through melting and permanent casting, and characterization using X-ray Diffraction (XRD) analysis, Scanning Electron Microscopy (SEM), and corrosion testing. The results showed that adding nickel significantly increased the crystallite size and yield strength through a solid solution strengthening mechanism. The corrosion rate decreased linearly with increasing nickel content, indicating the role of nickel as an effective corrosion inhibitor. The main conclusion is that nickel can improve recycled brass's mechanical performance and corrosion resistance, significantly contributing to developing environmentally friendly and durable metal alloys for sustainable manufacturing applications.

In this study, the three-dimensional modeling and numerical simulation of the rolling process were carried out based on the Finite Element Method (FEM). This study analyzes von Mises stress distribution, maximum strain, and deformation patterns of the workpiece under compressive forces from two counter-rotating rollers. Three workpiece dimensions (20 × 20 × 200 mm, 25 × 25 × 200 mm, and 30 × 30 × 200 mm) were tested to evaluate the effect of cross-sectional size on load distribution and plastic deformation. The results show that von Mises stress ranged from 65.71 MPa to 460 MPa, with maximum strain from 152,000 µstrain to 723,800 µstrain. Larger cross sections provide wider contact areas, leading to more uniform stress distribution and enhanced plastic flow. These findings serve as a reference for optimizing rolling parameters in metal manufacturing to produce precise and defect-minimized products.