Metallurgical and Materials Engineering

Titanium Coagulants in Water Purification and Water Treatment Processes in Additive Manufacturing

Evgenii Kuzin — 2024-03-07

Considerable attention is paid to improving the environmental safety of additive manufacturing. The production of titanium products using powder metallurgy methods is characterized by a significant amount of water consumption, and therefore a significant amount of wastewater generated. The paper presents the main directions of using titanium compounds as coagulants for the post-treatment of natural (technical water treatment) and waste water from the additive production of titanium products. It has been established that in the processes of wastewater and recycled water treatment, titanium-containing coagulants are significantly superior to traditional coagulants based on aluminum and iron salts. Processes for preparing process water from surface sources using titanium coagulants also occur with high efficiency. Residual concentrations of pollutants when using titanium tetrachloride as a coagulant were on average 2-3 times lower than when using traditional reagents. The coagulation sludge (sediment) obtained as part of water treatment is titanium dioxide in its composition and can be used in the future as a raw material for various industries.

The Effect of Liquidus Aging on The Performance of Phase-Stabilized Wax with Solid Nano Additives

Dwi Rahmalina — 2024-03-07

The present work assesses phase stabilized HW (hydrocarbon wax) with nano additives through liquidus aging treatment. The aging treatment is performed by storing the sample in the liquid phase at 130 °C for 250 hours. The sample performance is assessed according to the heating and cooling rate change before and after aging treatment. The finding indicates a severe decrement in the heating rate of thermal conductivity enrichment (TCE)-HW up to 24.4% and 7.5% for the discharge rate. The phase-stabilized HW performs better according to its heating rate, which only decreases by around 10.9% and the discharge rate by only 1.2%. The heating profile for HW shows a distinctive phenomenon, indicated by a two-step temperature spike of 6.8 °C and 11.8 °C at the solid-solid and solid-liquid transition. Contrary to that, the SHW presents a suitable profile where the temperature increases steadily until 86.3 °C with the average heating rate around 2.97 °C/min. The surface observation shows that the phase-stabilized polyethylene (HDPE) decreases the potential of void formation. As a result, the SHW maintains suitably the distribution of nano additives after aging treatment. Thus, phase stabilization is critical to ensure stable operation of HW with nano additives for the TES system.

The Enhancing PV stations for charging electric vehicles by utilizing shape memory alloy to track the sun and decrease fatigue

Amine RIAD — 2024-03-07

Integrating PV systems in large commercial areas for electric vehicle charging offers a comprehensive and strategic approach to sustainable business practices. This integration aligns economic, environmental, and social benefits, potentially reducing operational costs and boosting the overall brand image. In the pursuit of improving these types of structures, the use of shape memory alloy (SMA) emerges can be an ideal smart material. These materials can strengthen the structure as a damper and improve energy collection in PV system as mechanical tracker. This study is focused on developing a new smart actuator design that can be used as a sun tracker and mechanical damper in photovoltaic stations for commercial buildings. The proposed SMA actuator can significantly move in response to solar irradiation and can reduce fatigue by stabilizing mechanical stress during bad weather. In order to integrate the proposed actuator with the PV station in response to temperature and stress variation, a mathematical model has been developed. The study seeks to capture the thermo-mechanical behavior, including both superelasticity and the shape memory effect. The findings indicate that incorporating the SMA actuator in the PV station improves energy production efficiency by 19%, decreases vibrations by 85%, and contributes to the station's longevity. These technologies collectively offer environmental, economic, and operational benefits, making it a valuable component in the optimization of solar energy systems

Increasing Surface Hardness and Corrosion Resistance of AISI 410 Stainless Steel by Forming a Diamond-Like Carbon Thin Film

Agung Setyo Darmawan — 2024-03-07

AISI 410 stainless steel plays an important role in many engineering fields. The annealing process of this material will increase toughness. But this process will also reduce the hardness of the material. Plasma chemical vapor deposition was carried out to increase the surface hardness and corrosion resistance of AISI 410 stainless steel. In this study, the raw material was tested for metallography, hardness, and corrosion resistance. Then an annealing process was carried out on the raw material. The annealed material was also observed for metallography, hardness, and corrosion resistance. Furthermore, on the annealed material, the plasma chemical vapor deposition process was carried out with pressure variations of 1.0, 1.2, 1.4, and 1.6 mbar. Next, the material was tested for metallography with a scanning electron microscope to measure the layer thickness. The formation of diamond-like carbon was confirmed by the Raman Spectroscopy test. Annealed followed by plasma chemical vapor deposition processed AISI 410 stainless steel also tested for hardness and corrosion. The results showed that the annealed AISI 410 stainless steel underwent a phase change from martensite and retained austenite to ferrite and pearlite. The annealed raw material experienced a decrease in hardness and corrosion rate. After the annealed material was processed by plasma chemical vapor deposition, The thickness of the surface layer increased with increasing pressure. Along with that, the hardness and corrosion resistance increased.

Production of Fuel Oil from Waste Low Density Polyethylene and its Blends on Engine Performance Characteristics

Girish N. Desai — 2024-03-07

This research paper focuses on converting waste low density polyethylene (LDPE) plastic to fuel oil using thermal degradation through a pyrolysis reactor. The process involves heating the LDPE plastic in the reactor with purging of nitrogen gas to maintain an inert atmosphere in the reactor, with a retention time of 2-3 hours until it melts and forms vapour, which is then condensed in a container. The resulting fuel oil is analyzed for its physical properties and compared with standard diesel. The fuel oil produced has properties that agree with the standard, including a carbon residue of 0.01, density of 785.1 kg/m³, flash point of 68^oC, gross calorific value of 44,141 kJ/kg, kinematic viscosity of 2.18 cSt, pour point of -50^oC, and sulfur content of 32 ppm. The fuel oil is then subjected to engine performance and emission tests in a CI Engine by blending it with diesel. The results show that a diesel engine can run on a blend of 50% fuel oil and 50% diesel fuel, but the engine vibrates when the fuel oil content exceeds 50%. The oil-diesel blend has lower brake-specific fuel consumption and higher exhaust gas temperature than diesel fuel, but it also produces higher NO_x, CO, HC, and smoke emissions than diesel. Overall, the blend has significant advantages over conventional diesel fuel in terms of fuel efficiency, but it also has some drawbacks in terms of emissions.

Experimental Investigation on High Performance Green Concrete (HPGC) Produced with Iron Filings

Hawra Mohamed Ali M. Taher — 2024-03-07

The acronym "HPGC" refers to "high performance green concrete." This breakthrough is significant because it moves the industry closer to its goal of replacing concrete with eco-friendly alternatives that claim superior mechanical qualities, thereby making concrete a more sustainable building material. When working with metal, a fine powdery dust known as "iron filings" is inevitably created. The purpose of this study was to evaluate the usefulness of iron filings as a fine aggregate in building projects. An experiment was conducted to examine the mechanical iron filings' effects on concrete's characteristics utilised as a supplement to sand. Using a range of sand replacement percentages (0% (control mix), 10% (treatment mix), 20% (treatment mix), and 30% (treatment mix)), the compressive, split-tensile, and flexural strengths of 35 concrete specimens consist of cubes, cylinders, and prisms were tested after 28 days of treatment in water. The findings indicated that the mechanical qualities of HPGC were enhanced when iron filings were used in place of sand, but that the concrete's slump value and workability were diminished. Therefore, only 30% of the sand (fine particles) should be substituted by weight with iron filings in the concrete mix, depending on the desired strength attribute. In this case, the concrete's compressive strength is increased by 13.2%, split-tensile strength by 21.1%, and flexural strength by 49.88%, all by replacing 30% of the sand (fine particles) with iron filings. Therefore, employing iron filings in concrete will help with recycling and waste reduction.

Effect of SiC Particles on Mechanical Properties of Stir-Friction Welded Al/SiC Composites Fabricated by Lost Foam Casting

Moe Rabea — 2024-03-07

This study investigates the effects of inserting sub-micron hard silicon carbide (SiC) particles in a welded zone of aluminum (Al)/SiC metal matrix composite. Two parts of Al/35 wt. % SiC composites fabricated by lost foam casting (LFC) were welded together using friction stir welding (FSW) process. As reinforcement, 5 wt. % of SiC particles were inserted in the welding zone of the composites to enhance their microhardness and tensile strength as well as alleviate their thermal shock and weight loss/abrasion resistance. The optical images showed a good dispersion of SiC particles in the welded zone that resulted in a higher microhardness and tensile strength. The presence of well-dispersed SiC particles exhibited a good shock resistance of the composite even at higher temperatures, and lower weight loss (better corrosion performance) under salt spray test and a harsh 5% w/v NaCl solution for the presence of a hard equilibrium SiC and Al₄C₃ phases with further addition of SiC particles.

Applying Powder Technology to Improve the Performance of Copper Alloys used in HVAC Pipe Underground

Khaldoon Hussein Hamzah — 2024-03-07

The use of powder technology to enhance the performance of copper alloys in underground HVAC pipes. Powder technology, which includes processes like powder metallurgy and nanomaterial integration, allows for precise customization of copper alloys to meet specific requirements for subterranean HVAC systems. This research aims to develop more durable, long-lasting materials that ensure the reliability and effectiveness of subterranean HVAC pipes, offering insight into the cutting-edge methodology influencing the direction of subsurface HVAC systems. A pipe design with a diameter of 1in and a length of 500 mm was cast from copper powder materials, Cu and CuNiSiCr, to determine the differences in results. Three underground depths and powder thicknesses were used for pressure and powder thickness, with varying results for each depth. The depth of an underground pipe affects vertical force, stresses, and deformations in Cu powder. The deformation value increases with depth, reaching 0.57 mm at 3 meters. The stress increases with depth, reaching 0.54 MPa. The quality of CuNiSiCr powder improves with changes in powder quality, with deformation decreasing to 0.05 mm at 1 meter depth. Increasing copper powder tube thickness improves mechanical stress, with stresses nearly nonexistent at 3 mm thickness.