Semisolid forging of Al-10%Mg near the solidus line temperature was conducted. Al-10%Mg could be forged at a 50% reduction without cracks occurring. The casting structure of the metal changed to a plastic forming structure. Tensile stress, proof stress and elongation were also improved by semisolid forging. In particular, the elongation was remarkably improved. Improvement of proof stress was less than that of tensile strength or elongation. Fe was also added to Al-10%Mg to make a model alloy representing recycled Al-10%Mg, and semisolid forging was conducted. Elongation decreased, but tensile stress and proof stress increased slightly (by approximately 10%) with the addition of Fe. Semisolid forging was found to be useful for reducing the undesirable effects of the addition of Fe content on various mechanical properties of Al-10%Mg.

This work investigates the short-circuit (SC) reliability of Split-Gate (SG) versus planar 4H-SiC MOSFETs through TCAD simulations. While SG-MOSFETs effectively reduce gate-drain capacitance and improve switching performance, SG-MOSFETs exhibit enhanced short-circuit failure effects. Structural optimization—such as thicker drift regions, extended gate lengths, and narrowed JFET widths—can improve SC withstand time (SCWT). However, SG-MOSFETs suffer from intensified electric field crowding and enhanced drain-induced barrier lowering (DIBL), leading to greater post-SC leakage and thermal instability. Results suggest SG-MOSFETs require careful field and oxide engineering to ensure reliability under fault conditions.

This study investigates the influence of active cell geometry on the static performance of 10-kV 4H-Silicon Carbide (SiC) Junction Barrier Schottky (JBS) diodes. Two types of diodes were fabricated and characterized, one with a hexagonal cell and the other with a stripe cell. While forward conduction characteristics were comparable, the reverse leakage current of the hexagonal cell was more than two orders of magnitude lower than that of the stripe cell at 8 kV. 3D TCAD simulations revealed that this discrepancy stems from strong electric field concentrations both at the bottom corners of the P + junctions and at the center of the Schottky contact in the stripe structure. These localized fields reduce the Schottky barrier height and enhance electron injection. In contrast, the hexagonal cell exhibited a more uniform electric field distribution in both regions, effectively suppressing leakage current. These findings underscore the critical role of active cell geometry in achieving robust reverse blocking performance in ultra-high-voltage SiC JBS diodes by clarifying the physical mechanisms contributing to leakage current behavior.

Wastewater of domestic kitchen (KWW) may contain significant quantity of cooking oil residues and form problem of blocking domestic sewage pipe as cooking oil accumulated and clump inside the sewage pipe requiring cleaning and process for the removal of clumped oil residues. This study was designed to examine the efficiency of synthetic filter consisting of walnut shells in the removal of cooking oil residues from kitchen wastewater in addition to improve other wastewater variables such as pH, electric conductivity and total dissolved solids. where all collected kitchen wastewater samples were examined during November 2024 in Technical College of Al-Musaib lap. The synthetic filter was prepared by using a polyethylene plastic tube with 30 cm length and 10 cm diameter giving a volume of 2336.5 cm3. This tube had two ends where the upper end for receiving kitchen wastewater while the lower end for the draining. About 150 g of walnut shells with various sizes were placed in the synthetic filter where the upper end was linked to the pipe of kitchen sink while the lower end was connected to draining plastic container in order to examine the wastewater containing cooking oil residues. This study was proceeded at lab scale and the examination was carried out firstly via filtering wastewater using only Whatman filter paper to act as control and secondly via synthetic filter containing walnut shells which was repeated three times. A total of 2000 cm3 domestic kitchen wastewater was obtained and divided into 4 subsamples of 250 cm3 each where the sample was used for control test while the remaining 3 subsamples used for walnut shells filter. The obtained results have shown that mean pH value of control sample was 9.1 ± 0.2 while it was almost similar for the walnut shells filter samples and varied from 7.5 ± 0.2 to 7.6 ± 0.1. For wastewater electric conductivity electric conductivity ( EC), it was found that control sample had higher mean value of 3192.5 ± 317.7 µs/cm and the walnut shell filter samples have had lower mean values varying from 2425.3 ± 295.0 µs/cm to 2754.4 ± 44.55 µs/cm. Regarding wastewater total dissolved solid (TDS) content, it was recorded that control sample had much higher mean value (3072.67 ± 47.5 ppm) than those of walnut shells samples which ranged from minimum value of 1381.0 ±13.0 to maximum value of 1414.0 ± 74.0 ppm. In case of cooking oil residues, the study has recorded significantly higher mean value of 7.3 ± 0.8 gm in control wastewater sample while walnut sells filtered samples had much lower mean values varying from 2.94 ± 0.08 to 3.3 ±0.2 gm. It seems very clearly that walnut shell filter has removed significant quantity (Probability ≤ 0.05) of cooking oil residues from the kitchen wastewater.

Aluminum extrusion plays a critical role in lightweight structural applications and circular economy strategies. However, extrusion process design is constrained by competing objectives: increasing productivity through higher ram speeds or increased die-hole count improves throughput and material utilization yet simultaneously elevates force demand and defect susceptibility. In this work, a numerical statistical framework is proposed to identify circularity-tolerant process windows, defined as multi-objective design regions that balance productivity, product quality, and sustainability performance. A three-factor Taguchi design was employed to systematically vary ram speed, billet temperature, and die-hole count in the extrusion of AA6063. Twenty-seven full 3D thermo-mechanical extrusion simulations were conducted using the DEFORM finite element platform employing an Arrhenius-type constitutive model from literature. Key extrusion responses maximum ram force, local damage indicator, and total displacement were analyzed using Principal Component Analysis (PCA) to reveal correlations and trade-offs between productivity-oriented parameters and quality-related responses. The results demonstrate a clear divergence between productivity drivers (ram speed, die-hole count) and process capability indicators, providing quantitative evidence of the inherent productivity quality trade-off. The proposed framework enables the identification of robust extrusion operating regions suitable for circular manufacturing scenarios in aluminum extrusion. The proposed framework is particularly relevant for extrusion scenarios where process robustness must be ensured under increasing material and operational variability, such as those anticipated with higher recycled content.

The growing use of extruded aluminum components in vehicle structures necessitates both strength and ductility to meet energy absorption requirements. In this study, a new compression calibration method for multi-chamber, hollow sections was developed with the aim of improving dimensional accuracy while enhancing the ductility of AA6061 extruded profiles. The influence of this method on mechanical properties was investigated through uniaxial tensile tests, three-point VDA bending tests, and axial crush tests. The uniaxial tensile test results revealed a reduction in the (logarithmic) strain at necking, while no significant changes were observed in yield and ultimate tensile strengths. On the other hand, the VDA tests showed a systematic increase in the normalized bending angle, indicating improved energy absorption characteristics. Visual inspection and the absorbed energy obtained by axial crush tests supported the findings in the VDA tests, indicating the compression calibration method enhances the crushability of extruded AA6061 profiles, although this improvement is not identified in standard tensile data. Overall, this work introduces a new, industrial calibration method for hollow extrusions that also enhances crushability.

This study investigates an adaptive die concept for cold extrusion that actively modulates radial preload during the main forming and ejection phases. A Gaussian process regression (GPR) surrogate, trained on fewer than 400 finite-element simulations, provides a highly data-efficient model capable of accurately predicting geometric tolerances, residual stresses, and process forces. Experimental spot measurements validate the physical trends captured by the surrogate, demonstrating reliable reproduction of the underlying mechanical interactions. The results show that increased preload during forming enables micrometer-level calibration of final diameters, while higher preload during ejection promotes beneficial compressive residual stresses at the cost of elevated ejector forces. A part-to-part control strategy effectively improves accuracy by independently steering two target properties through separate preload adjustments. Furthermore, a reinforcement learning-based controller, enhanced by flow stress estimates derived from hardness measurements, reduces variance and compensates for stochastic fluctuations in material and friction conditions. Overall, the adaptive die system, combined with surrogate-and RL-based control provides a robust foundation for achieving high dimensional precision and stable product properties under future variability scenarios, such as green steel and sustainable lubrication systems.

Aluminum 7000 series alloys are widely used for aerospace and transportation applications due to their high strength-to-weight ratio. This research investigates the impact of zinc (Zn) and magnesium (Mg) content on the hot extrudability and tribological behavior. Elemental quantities straight away impact flow stress, determining the manufacturing parameters, whereas galling and adhesion frequently degrade tool life. This work illustrates that by assessing essential ram speeds and temperature limits, adjusting Zn and Mg concentrations considerably improves the extrudability limit. A decreasing flow stress during deformation reduces micro-cracking tendency and improves surface quality. The findings provide critical compositional guidelines for high-strength aluminum alloys, effectively balancing processing efficiency with improved surface quality and reduced element adhesion behavior, ensuring better industrial outcomes for advanced structural components.

The Guided Material Flow (GMF) process is an advanced variant of the Samanta process designed for the net shape cold extrusion of gears. The GMF process employs a modified die geometry to control material flow and significantly reduce maximum tool loads, effectively overcoming traditional process limitations. Key advantages include enhanced tooth tip strength and a reduction in face end deformations, which are characteristic defects in the conventional Samanta process. Minimising these deformations reduces the requirement for subsequent machining and enhances overall material efficiency. A numerical dataset was generated to train and validate data driven surrogate models, facilitating rapid process analysis without the computational cost of continuous Finite Element Analysis (FEA). The models developed in this paper enable the precise prediction of critical process outputs, including maximum punch force, die filling behaviour, material utilisation and strain hardening at the tooth tip. This paper details the numerical data acquisition, the specific training and validation methodologies of the machine learning models and demonstrates their capability to accurately predict complex process outcomes when varying the geometry of the die active surface in the GMF process.

High friction in aluminum hollow profile extrusion limits material flow, process stability, and productivity. Ultrasonic vibration offers a promising approach to reduce friction, yet its application to industrial porthole dies is still insufficiently explored. This study presents the development and investigation of an ultrasonic die sonication system for aluminum extrusion. Finite element extrusion simulations demonstrate that reduced friction leads to lower extrusion forces, decreased profile exit temperatures, and improved material flow. A modified porthole die enabling ultrasonic excitation at multiple positions was designed accordingly. The vibrational behavior of the die was analyzed using three-dimensional modal and harmonic finite element simulations. Suitable excitation frequencies between 18.5 and 23 kHz were identified and experimentally validated by laser vibrometry, confirming effective transmission of ultrasonic vibrations into the die. The simulation results demonstrate the feasibility of ultrasonic die oscillation for aluminum hollow profile extrusion and provide a solid basis for forthcoming extrusion trials and further process optimization. The system was implemented, approved, and is now available for upcoming experimental trials.