Electron backscattered diffraction is widely used for phase and orientation imaging of crystalline specimens. Despite the inherent complexity of diffraction images, current analysis methodologies typically focus on the position of Kikuchi bands or direct comparisons between experimental and simulated patterns. These approaches require prior knowledge of the phases to be analyzed, limiting their applicability in certain scenarios. This paper introduces an alternative methodology, crystallographic analysis of lattice metric, which extracts phase and orientation information directly from the registered diffraction pattern without requiring predefined standards. The paper outlines the methodology, discusses limitations, and demonstrates possible application in phase analysis, lattice parameter ratio mapping, and qualitative lattice distortion mapping.
The paper describes an experimental study of thin layers obtained using the vibrating electrode method. Vibrating electrodes are used because they are effective for producing layers with high hardness and wear resistance. Before the depositions, the base material was polished with abrasive paper to remove any oxides and impurities. Furthermore, four electrodes made of Ti, TiC, WC, and stellite were used to deposit different layers on the surface of steel blades using an Elitron 22 installation. The tungsten electrode was used to improve mechanical properties, whereas the titanium electrode increased corrosion resistance. Both the substrate and the deposited layers have had their chemical composition, microstructure, and hardness analyzed. The substrate is made of mediumalloyed steel, which is commonly used to make plastic shredder blades. Following deposition, the samples were subjected to final heat treatments, including quenching and tempering. Furthermore, microhardness and microstructural analyses were conducted to assess the properties and surface morphology of the coatings.
This study qualitatively demonstrates the role of Ni addition on transient liquid phase (TLP) Sn-Ag-Ni solder alloy through multiple reflow cycles, focusing on the formation, stability, and transformation of intermetallic compounds (IMCs). The optimal incorporation of 0.3 wt.% nickel (Ni) into the Sn-Ag solder alloy promotes the formation of thermally stable, high-melting-point IMCs, enhancing the structural integrity of the solder joint. Phase diagram analysis using Thermo-Calc software qualitatively confirms the coexistence of Ag3Sn, Ag4Sn, and Ni3Sn4 with the (3-Sn phase, supporting their structural role in solder joint stability. Thermodynamic analysis shows that Ag3Sn IMC has the highest favorability for formation and stability at room temperature, while Ni3Sn4IMC enhances high-temperature performance. Differential Scanning Calorimetry (DSC) analysis qualitatively supports these findings, revealing two distinct melting peaks. The first peak relates to the eutectic melting temperature, while the second peak relates to the high melting temperature. The Sn-Ag-Ni solder alloy is more thermally stable than Sn-Ag. Heat flow data indicate enhanced phase transformations and improved thermal stability in Ni-containing solder alloy. This study provides a qualitative understanding of the addition of Ni and its effects on the IMC evolution, phase inter-reaction, and high-temperature reliability critical for optimizing lead-free solder alloys in electronic packaging applications.
This study investigates the development of a superhydrophobic coating on steel substrates using a factorial design method, focusing on its anti-corrosion applications. The coating formulation includes palm slag, stearic acid, expanded polystyrene (EPS), and titanium dioxide (TiO2), with the coating applied to metal substrates. The superhydrophobic properties were assessed through water contact angle measurements, achieving a high degree of water repellence. Surface roughness was analysed using a 3D profilometer, revealing hierarchical nanostructures that contribute to the coating's hydrophobicity. The optimized formulation demonstrated effective corrosion protection, making it suitable for various industrial applications. The use of factorial experimental design (FED) proved highly effective in identifying optimal levels for the coating components, enhancing its performance. This research offers valuable comprehension into the formulation and characterization of superhydrophobic coatings, with significant implications for their use in diverse environments.
The Al-Co alloys corrosion resistance of various Co compositions (0.5-5 at.% Co) at different sintering times (4 h, 8 h, 24 h, 48 h, and 72 h) for 25 degrees C in (1M) hydrochloric acid electrolyte was studied by employing the electrochemical impedance spectroscopy (EIS) and the tafel polarization. Raman technique was used to identify the surface film of aluminum and its alloys, and scanning electron microscope (SEM) coupled with energy-dispersive X-ray spectroscopy (EDS) was used to determine the microstructure of the materials. In comparison to undoped aluminum, the Al-5 at.% Co material sintered at forty-eight hours exhibited outstanding corrosion performance. Pitting is discernible in the microstructure of sintered materials, particularly within the Al9Co2 phase. This phase exhibits faster corrosion compared to other intermetallic compounds such as Al13Co4. In terms of crystal structure and chemical composition of the dopant, the Al-Co intermetallic compounds are classed as a function of their relative nobility.
To explore an alternative green metallization strategy for nonconductive plastics, a conductive polypyrrole (PPy) precoat was prepared by in-situ interfacial polymerization of pyrrole on printed circuit boards (PCBs) and the electrodeposition of Cu on PPy precoat was investigated using both voltage-controlled method and current-controlled method. A uniform PPy film was successfully obtained on the PCB surface through modifying the PCB wettability and optimizing the pyrrole solution. Electrochemical measurements showed that sufficient polarization was necessary for the electroreduction and growth of Cu crystals on the PPy precoat due to its high electrical resistance. The presence of through-holes adjacent to copper in PCB boards demonstrates that constantcurrent electroplating enables effective deposition of uniform, adherent copper layers on polypyrrole (PPy) - pretreated substrates, establishing a viable alternative to conventional electroless copper plating for through-hole metallization in PCB manufacturing.
This study examines the strength characteristics and microstructural evolution of welded joints in X10CrWMoVNb9-2 (P92) steel piping used for pressure-critical components in power generation systems. The research evaluates the effects of prolonged thermal exposure through 3,000 and 10,000 h annealing cycles at 650 degrees C. Microstructural analyses were conducted using scanning electron microscopy (SEM), while mechanical performance was assessed via tensile testing. The investigation identified a direct correlation between microstructural degradation and diminished mechanical performance, a critical factor for high-temperature applications. Strength reductions were attributed to progressive coagulation of M23C6 carbides and Laves phase precipitation. The comparative analysis quantified property changes between the as-received parent material and weld metal, establishing baseline-to-aged condition performance metrics. These findings underscore the importance of microstructural stability in maintaining the operational integrity of P92 steel components under prolonged thermal stress, particularly in ultra-supercritical power plant environments.
The rise in demand for self-compacting concrete (SCC) results in an associated rise in the use of primary components like cement and aggregate. Furthermore, environmental deterioration, climate change, and pollution are significant environmental concerns. The problem of environmental degradation caused by the disposal of industrial waste, particularly coal bottom ash (CBA) from thermal power plants, requires urgent attention. Given the significant shortage of essential materials like cement and aggregates, it is crucial to find alternative materials to replace cement. There is a pressing need for high-quality materials that can effectively substitute for cement and withstand high temperatures. A key challenge in improving the fire resistance of concrete at elevated temperatures is maintaining its compressive strength. This research seeks to explore the effects of substituting ground CBA for cement on the compressive strength and fire resistance of self-compacting concrete (SCC). Four SCC-CBA mixtures were created by replacing 0%, 10%, 20%, and 30% of the cement weight with ground CBA. Both CBA-SCC and control SCC specimens were subjected to elevated temperatures of 200, 400, 600, and 800 degrees C for one hour, and mass losses along with compressive strength reductions were assessed post-heating. The results indicate that the highest compressive strength for SCC is achieved with 10% ground CBA. All mixtures met the specified strength requirements in 28 days, with compressive strength values ranging from 30 MPa to 39 MPa. At 400 degrees C, the SCC with 10% ground CBA showed greater mass and strength degradation compared to the control samples.
The ab initio pseudopotential method relies on Density Functional Theory (DFT), utilizing the generalized gradient approximation (GGA) as outlined by Perdew-Burke-Ernzerhof (PBE). Implemented through the Siesta program, this method examines the structural and optical properties of the nickel-iron alloy (Fe-Ni) that crystallizes in the FeNi3 structure. This approach is highly regarded for its accuracy in predicting the crystal structure and properties of FeNi3. The computed structural parameters align closely with both theoretical and experimental data, confirming the reliability of these predictions. The lattice constants, calculated at zero pressure, match previously reported theoretical and experimental results. Furthermore, the computed properties, including the Band Structure, Total Density of States (DOS), and Partial Density of States (PDOS), and elastic constants values for the alloy, suggesting its suitability for specific applications in targeted fields.
Advanced packaging technologies, such as Intel's Embedded Multi-Die Interconnect Bridge and Foveros, have revolutionized semiconductor integration by enabling compact, high-performance devices through 3D stacked die configurations. This study focuses on the warpage effects in 3D stacked die configurations using copper-copper (Cu-Cu) hybrid bonding under thermal cyclic conditions, which are critical for ensuring semiconductor device reliability. The research employs ANSYS simulations through Thermal-Structural Coupling to analyze temperature distribution, thermal strain, and Von-Mises stress across different Cu-Cu hybrid bonding heights. Findings indicate uniform heat transfer across thermal cycles, with significant stress concentrations at corner bonding interfaces. Reducing Cu-Cu hybrid bonding height from 0.025 mm to 0.017 mm mitigates thermal strain and stress, with the 0.017 mm height proving optimal for minimizing warpage effects. This research provides insights crucial for enhancing semiconductor packaging reliability. It addresses industry demands for energy-efficient and compact electronic devices and supports industry standards, cost-efficiency, and innovation in semiconductor engineering.
The increasing demand for flexible, lightweight, compact, and cost-effective electronic products has led to a growing preference for Flexible Printed Circuit Boards over Rigid Printed Circuit Boards. However, thermal challenges during the reflow soldering process can significantly impact FPCBs. When exposed to elevated temperatures, Flexible Printed Circuit Boards are highly susceptible to deflection and thermal stress. This study examines the impact of temperature profile on FPCBs during the reflow soldering. Deformation measurements for both FPCBs and Rigid Printed Circuit Boards were obtained using a KEYENCE LK-G152 laser sensor installed at a reflow oven's entry and exit points. The experiment evaluated two temperature profiles, soaking and ramp profile, as variables. Findings revealed that FPCBs experienced greater deformation under the ramp profile, whereas RPCBs exhibited more deformation under the soaking profile. This research provides valuable insights for engineers and Printed Circuit Board designers, offering practical guidelines for optimizing mass production in the microelectronics industry.
This study examines the impact of Dimethylformamide, DMF/Acetone ratio (60/40, 70/30 and 100/0) and stirring time (16 hours and 24 hours) on Polyvinylidene Fluoride electrospun fibers. Total of six samples were prepared at 12% solution concentration were electrospun at 20 kV, 10 cm tip-to-collector distance, and 1 mL/h flow rate. Morphological analysis showed that a 70/30 ratio produced finer fibers with fewer beads than 60/40 ratio, while prolonged stirring increased fiber diameter. Electrical analysis confirmed the lowest resistance and highest conductivity for these fibers. The 70/30 ratio and 16-hour stirring time technique optimized fiber structure and electrical performance for advanced applications.
With the continuous expansion of copper smelting scale, copper concentrate resources are in serious shortage, resulting in the utilization of low-grade complex copper concentrate, which leads to anode passivation in copper electrolytic refining process due to high impurity contents. Aiming at this problem, in order to stabilize the cell voltage and improve the overall efficiency of the electrolytic refining process when treating high impurity anode copper, the effects of additives, electrolyte free sulfuric acid and technological operation on the cell voltage change were studied based on the unique electrolyte feeding movement mode of parallel flow technology. The results showed that in order to stabilize the cell voltage of electrolytic high lead anode copper at high current density, it was suggested that the amount of bone glue should be 40-90 g/t, the amount of thiourea should be less than 100 g/t, and the concentration of free sulfuric acid should be 160-180 g/L.
This review aims to explore the processing-structure-property relationship of Zn and Zn-based alloys developed for biodegradable cardiovascular stents. It assesses how conventional and advanced manufacturing techniques, including casting, extrusion, laser cutting, and additive manufacturing, affect the microstructure, mechanical performance, and degradation behavior of Zn-based materials. Particular emphasis is placed on the potential of additive manufacturing due to its ability to enhance microstructure, corrosion, and mechanical properties by adjusting the processing parameters and producing patient-specific stent geometries with enhanced precision and functionality. The review also addresses the unique processing challenges associated with Zn, such as high vaporization during laser processing. Additionally, the review identifies key knowledge gaps and outlines directions to support future research to advance Zn-based stents toward clinical translation as biodegradable cardiovascular stents.
The study analyzed two selected representative HSLA steels rolled at the Krakow branch of ArcelorMittal Poland S.A. The aim of the analysis was to determine the effect of parameters such as strain and cooling rate on the onset temperature of the transformation from austenite to ferrite. Dilatometric tests were carried out, followed by strain dilatometry. The cooling rate was varied and its relationship with the temperature of the beginning of austenite to ferrite transformation (Ar3) was determined. In the second part of the study, the subject literature was analyzed to find out how quickly the Ar3 temperature could be calculated. The available equations for calculating the Ar3 temperature were checked. However, the results of the calculations were not consistent enough to use these equations in the actual process. Therefore, the authors decided to develop their own equation-the proposed solution allows the calculation of the Ar3 temperature for the two selected HSLA steels mentioned above with an accuracy of several degrees and a correlation of more than 90%.
The research aimed to assess the condition of the main steam pipelines and peripheral welded joints after long-term exploitation under creep conditions that operated for a time significantly exceeding the design time. Secondary steam pipeline elements made of 10CrMo9-10 steel operated for 240 000, 280 000, and 308 000 h were under investigation. The mechanical properties of the welded joint areas were determined in destructive tests. In particular, the brittle transition temperature and mechanical and plastic properties at room and elevated temperatures were determined. The effect of long-term operation on the tested pipelines' strength, plastic properties, and impact strength was also investigated. Based on the completed creep tests, the extrapolation method determined the residual life. The available residual life was estimated, which is the safe period of further operation for the operating parameters of stress or and temperature Ir. The applied methodology and the adopted procedure will be used to assess the condition and further operation time prediction of welded joints of power equipment pressure parts operating under creep conditions.
FDM (Fused Deposition Modeling) technology, initially used to create prototype models, has gained importance in the serial production of structural elements in various fields of engineering. In this paper, the influence of the internal structure and infill density on the strength properties of samples printed using FDM technology was analyzed. Static tensile tests were performed on samples made of ABS (acrylonitrile butadiene styrene) and PA6+CF15 (polyamide reinforced with 15% carbon fibre) materials, with different filling levels: 25%, 50%, 75% and 100%, using two internal structures-linear and honeycomb. The experimental results were verified by numerical analysis. The obtained results allow for a better understanding of the relationships between printing parameters and the mechanical characteristics of printed elements, maximum strength and material consumption efficiency.
Foreign object damage (FOD) is one of the main limiting factors for the life of aero-engine blades. In order to summarize the impact law and predict the damage gap caused by the impact of foreign objects on titanium alloy blades, the dynamic simulation calculation of foreign object damage at the inlet edge of an aero-engine guide vane was carried out with a specific blade as the research object, a cylindrical steel nail with high probability on the airport pavement as the foreign body and the most possible angle caused by the inlet flow field as the impact angle. The study found that: (i) The notch depth consists of two components: the initial depth at impact and the subsequent expansion due to centrifugal stress. (ii) The depth of the notch is always greater than the width. The maximum width of the notch is approximately equal to the cross-sectional diameter of the steel column. (iii) The relationship between notch depth and notch width is a quadratic function. (iv) The changes of notch depth with relative kinetic energy and steel column mass, and the changes of impact angle, maximum impact force and impact time with steel column mass are all power functions. With the increase of impact position, the relative kinetic energy of the steel column increases, and the change law is a quadratic function. (v) For the same foreign object, there is a critical value when the impact height increases. When the impact position is lower than it, the notch depth increases continuously. On the contrary, the notch depth decreases. Similarly, there is a critical value in the process of increasing relative kinetic energy. Smaller than it, the notch depth continues to increase, while larger than it, the notch depth continues to decrease. These findings provide data to support the diagnosis of blade damage under field conditions, and provide a theoretical basis for the design of blades against foreign object damage.
The work presents a solution for a steel-concrete ceiling girder made without the use of welding. Experimental and numerical tests carried out on a real-scale girder model were discussed, on the basis of which the value of the destructive load, the value of the of the destructive bending moment and the amount of girder deflection were determined. The results obtained from experimental tests were consistent with the results of numerical calculations. The bending load-bearing capacity was calculated for various variants of the girder structure, showing that it depends mainly on the height of the steel section and the type of steel from which it was made. The impact of the other analyzed parameters is less important. Eliminating the welding process during the construction of the girder allows for reducing the energy consumption of its production while maintaining strength parameters comparable to elements in which welding was used. Moreover, the connector attachment technique used (unlike welding) does not cause any microstructure transformations, allows maintaining the homogeneity of the material and avoiding internal stresses and deformations.
This study focuses on synthesizing new electrolyte materials for solid oxide fuel cell (SOFC) with the composition of Ce0.8-x MnxSm0.2O1.9-s (x = 0, 0.025, 0.05, 0.1). The main aim is to investigate the effect of varying molar concentrations of manganese (Mn) as a secondary dopant on density, phase composition, and ionic conductivity of samarium-doped ceria (SDC). Accordingly, X-ray diffraction (XRD) and impedance spectroscopy (IS) were employed to characterize the samples. Mn-doped samples sintered at 1400 degrees C for 5 hours exhibited a single-phase cubic fluorite structure with larger lattice parameters and volumes compared to the undoped sample. All samples achieved a high relative density exceeding 94%. Notably, the sample with 10 mol% Mn reached a relative density of 99.6%. Impedance data revealed that the ionic conductivity of the Mn-doped samples was enhanced by an order of magnitude compared to the undoped samples. This indicates that Mn is a promising dopant for SDC in electrolyte applications for SOFCs.
