Energy Dispersive Spectrometer Analysis Research Articles

Characterizations and solubility profile of novel senary SiO2–CaO–Na2O–P2O5–CaF2–SrO glass structure modified with Nb2O5

The solubility/degradability of bioactive glasses play crucial role in bone tissue engineering applications owing to the release of ions from their structure, which exert therapeutic effects on tissues. The present study evaluates the findings of a detailed investigation on the main features and solubility behaviors of newly formulated Nb incorporated glasses (Nb-BGs). New glass formulation in SiO2–CaO–Na2O–P2O5–CaF2–SrO–xNb2O5 (x: 0.0, 0.5, 1.0, and 1.5 mol. %) system was successfully synthesized by melt-quenching technique. Glass composition was verified with Energy Dispersive X-ray Fluorescence spectrometer analysis and its amorphous nature, functional groups of the matrix and morphological features were identified via X-Ray diffraction analyses, Fourier Transform Infrared Spectroscopy and Scanning Electron Microscope analysis, respectively. Network connectivity (NC) of the Nb-BGs was assessed with respect to the role of Nb2O5 in the glass matrix as network former, modifier, or both. In order to evaluate the in vitro solubility of Nb-BGs, released concentrations of particular ions from the glass compositions were determined at certain time points and comprehensively discussed with several mathematical models such as zero-order, first-order, second-order, Higuchi, and Korsmeyer-Peppas for the first time. Results showed that the incorporation of Nb2O5 (up to 1.5 mol. %) increased the density, oxygen density as well as NC values of newly formulated glasses. Si, Na and Ca ions which play a main role in well-defined Hench's mechanism followed mostly second-order release kinetics for all glasses in the mathematical models studied. When the Nb content increase (to 1.5 mol. %) in glass composition, the release mechanism of Si ion according to Korsmeyer-Peppas model shifts from the diffusion mechanism to an erosion-dominant release mechanism.

Chemometrics as a tool for monitoring corrosion degradation of the selected alloys in real conditions

AbstractMonitoring of the corrosion process of alloys in real conditions often results in extensive data, which is characterized by complex interdependence, but by a large degree of mutual deviation. First of all, the large dispersion of the obtained results makes it very difficult to draw accurate conclusions about the real influence of the tested parameters on the corrosion behavior of alloys. On the other hand, in many cases, the high interdependence between the corrosion factors can also greatly burden the analyzed system and thus make it significantly difficult to recognize the main influence. Multivariate analysis, especially the principal component analysis, is becoming increasingly popular in processing of this type of data, due to its ability to recognize and eliminate redundant data. The aim of this study was to examine the possibility of using multivariate analysis methods in the processing of the corrosion test results obtained under real conditions. Based on the obtained results, it can be concluded that used multivariate method in combination with energy dispersive spectrometer analysis can be successfully used to identify the most important corrosion factors (type of corrosion environment, exposure time and technological production processes), as well as their influence on the degradation of the tested TiNi alloys under the given conditions.

The interactive force between fat, oil, and grease (FOG) deposits and the effect of food waste disposers on kitchen drainage systems

Food waste disposers (FWDs) streamline kitchen waste management and facilitate waste classification, whether they would increase the potential of blockage in kitchen drainage system is still unknown. This study conducted a theoretical analysis of the interactive forces between fat, oil, and grease (FOG) deposits and their aggregation on pipe walls. The study involved grading food waste particles processed by FWDs using sieving and weighing techniques to determine the mean weight diameter (MWD) of various aggregations. A full-scale experimental system, implemented in a 60-m high test tower, simulated blockages in horizontal pipes of high-rise buildings. The effect of pipeline materials and particle sizes on blockage were examined by measuring the adhesion of deposits on horizontal pipes. Energy dispersive spectrometer (EDS) analysis suggested that liquid bridge force is a primary factor in aggregate formation. Hand-cut particles formed aggregates with the highest MWD value. Particle size analysis revealed that sizes ranging from 2.36 to 4.75 mm, 1.18–2.36 mm, and 0.60–1.18 mm constituted over 80 % of particles ground by FWDs, with an average size of 2.16 mm. Results of full-scale experiment indicate particle diameters, friction coefficients and lipophilic coefficient significantly affected the propensity of these aggregates to adhere to pipes. Notably, particles processed by FWDs tended to cause blockages more frequently than hand-cut particles. These findings elucidate the deposition mechanism of FOG deposits and offer strategies to reduce blockages in kitchen drainage systems, such as reducing current grinding particle size by 18 % to 1.77 mm or selecting pipes like cast iron and high-density polyethylene.

High-temperature oxidation resistance behavior and mechanism of HfSiO4-modified C/SiC composites

To enhance the oxidation resistance of C/SiC composites, HfSiO4 was introduced into C/SiC composites to modify the matrix utilizing two cyclic alternating preparation modes, thereby yielding the C/SiC-HfSiO4 composites with a composite matrix. Using X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy-dispersive spectrometer (EDS), and thermogravimetric-differential thermal analysis (TG-DTA), a comprehensive investigation was conducted into the oxidation behavior and mechanism of the prepared composites. Results reveal that the C/SiC-HfSiO4 composites prepared using cyclic alternating preparation modes display the reduced oxidation mass loss and enhanced retention of flexural strength, despite of having higher porosity. In short, the introducing of HfSiO4 can effectively improve the oxidation resistance of C/SiC composites. The effects of the matrix particle refinement and the synergy between the HfSiO4 and SiO2 jointly lead to the enhanced oxidation resistance.

Investigation of dual work function metal (DWFM) gate stacks with ALD TaAlN and TaAlC for multi threshold voltages (VTHs) engineering in MOS device integration

This study investigates methods to modulate the effective work function (EWF) and control the multiple threshold voltages (VTHs) of metal-oxide-semiconductor (MOS) devices by applying metal electrodes with different work function materials (WFMs), including a single layer of n-type (TaAlC) and p-type (TaAlN) as well as their stacked structures, through atomic layer deposition (ALD). Dual-Work-Function-Metal (DWFM) gate is a crucial aspect of confirming the feasibility of metal gate stacks in MOS devices for a complementary metal-oxide-semiconductor (CMOS) integration scheme. The gate stack structure of p-Si/IL (Inter layer)/HfO2/DWFM (p/n-type compatible metal stack)/W exhibits good adhesion and even chemical composition distribution, as evidenced by transmission electron microscope (TEM) and energy dispersive spectrometer (EDS) analysis. By fabricating MOS capacitors using this WFM structure and extracting EWF from the measured capacitance-voltage (C–V) characteristics, EWF values of 4.62 eV and 4.99 eV were identified both before and after annealing using forming gas, indicating pWFM-like properties. These properties are attributed to the strengthened Al–O bonds and reduced CO peaks seen in x-ray photoelectron spectroscopy (XPS) analysis. The use of different Ta precursor from Tris(diethylamido)(tert-butylimido)tantalum(V) (TBTDET) as well as TaCl5 resulted in the increase of the EWF following the unique p-WFM like feature. As candidates for WFM electrode in metal-oxide-semiconductor field effect transistor (MOSFET) with the DWFMs (n/p stacks) were evaluated, resulting in a VTH of 0.84 V that places in the middle of the VTH shift range from 0.6 V (nWFM) to 1.16 V (pWFM), approximately. The DWFMs allow for modulation of the EWF, which in turn reduces ambiguity in addressing replacement metal gate (RMG) challenges and opens up new avenues for achieving multi-VTH solutions in CMOS integration schemes.

Temperature dependent deformation behavior and texture evolution in AA6082 aluminum alloy: An integrated experimental and crystal plasticity simulation approach

This research provides a comprehensive analysis of the texture and temperature dependent deformation behavior of the aluminum alloy AA6082. The study is performed using a combination of experimental deformation tests and computational simulations using a crystal plasticity (CP) framework. The primary objective is to identify the critical influence of temperature on local stress states and dislocation density within the material during tensile tests. From an experimental perspective, the study employs ex-situ deformation tests and subsequent electron backscatter diffraction (EBSD) data in combination with energy dispersive x-ray spectrometer (EDS) analysis at 200 °C and 400 °C. The experimental EBSD data are adopted, preprocessed and converted into a geometry file for the numerical simulations. On the computational front, a dislocation density-based material model is adopted for CP simulations. The physical and fitting parameters of the model are calculated, adopted from the literature, or calibrated by comparing the global simulation results with experimental stress-strain observations under uniaxial tensile load at room temperature, 200 °C and 400 °C. Empirical functions for solid solution strengthening, dislocation density, fitting parameters controlling mean free path and dislocation annihilation have been derived that can be used to quickly interpolate them for any intermediate temperature. These functions combined with other model parameters can now be used for temperature-dependent CP modeling of AA6082. The isothermal grain-scale simulation and ex-situ experimental results confirmed a noteworthy texture transformation at higher temperatures, characterized by a reduction in the primary Cube orientation and its transition into a Copper orientation due to the stretching process. The correlation between the experimental results and the simulations on macro- and micro-scales is reasonable, indicating the accuracy and effectiveness of the CP approach in predicting the temperature dependent deformation behavior and texture evolution in aluminum alloys.

The analysis of long-time-exposed tars from wood shingles from church roofs and facades in mid-Sweden

ABSTRACT Poor condition of roofs in terms of decay of shingles and loss of tar-based surface treatments has been revealed in a number of churches at various geographical locations in mid-Sweden. The condition of tars obtained from shingles of selected churches in mid-Sweden were analysed and obtained data were compared with geographical locations of the churches. According to gas chromatography-mass spectroscopy result, dehydroabietic acid was the dominant compound found in the exposed tars from the churches except in church of Malung where similar amounts of retene was found. Oxidised resin acids were found in exposed tars from the churches but not in commercially available pit burned tar. Tar from church shingles had higher char residues than the pit burned tar which was totally consumed when heated under nitrogen gas up to 750°C using thermogravimetric analysis. Scanning electron microscopy with energy dispersive X-ray spectrometer analysis revealed higher amounts of silicates in some exposed tars; however, these compounds constituted only a minor portion of the organic matter in these specimens. Based on the data obtained in the study other factors rather than simply geographical location of churches seemed to be of importance to explain differences of the investigated properties of the church tars.

Mechanical octacalcium phosphate coatings on the plasma electrolytic oxidized pure titanium for bio-implant use

In this study, OCP powder was used for mechanical coating on the plasma electrolytic oxidized (PEO) implant surface to improve bioactivity. PEO treatment was performed on the surface of the implant using a solution mixed with calcium acetate and calcium glycerophosphate, and creates porosity through a pulsed DC power supply. For compositional analysis, energy dispersive X-ray spectrometer analysis was employed to calculate OCP content and X-ray diffractometer analysis was used to confirm the crystal structure. Also, wettability, surface roughness, hardness, elastic modulus, and corrosion resistance testing were performed. Significantly, the reduction in OCP particle size decreased, and pore filling with OCP smaller particles increased as mechanical coating time increased from 0 to 12 h. Surface and cross-sectional morphology showed the presence of OCP on the substrate. Also, surface roughness, contact angles, hardness, and elastic modulus were reduced as mechanical coating time increased. Corrosion resistance was found to be the highest for mechanical OCP coating for 6 h surface treatment on the PEO-treated CW-Ti.

Thermocapillarity transition-induced unconventional thermal behavior and dilution in laser welding of metals with dissimilar sulfur content

An enhanced three-dimensional transient Thermal-Fluid-Dilution model, integrating a sub-model that accounts for surface tension, is proposed to investigate the unconventional thermal behavior and dilution induced by the surface-active element (sulfur) during the laser joining process of 304SS with higher sulfur content and pure nickel with lower sulfur content. Surface tension is modeled as a function dependent on local temperature and the concentration of the surface-active element (sulfur) at the free surface. The temperature and sulfur-dependent surface tension initially generate an unconventional driving force, subsequently leading to the transitions of heat transfer, flow pattern, and species dilution. Specifically, the inclusion of the sulfur effect results in a redistribution of larger surface shear stress along the transition boundary, causing unconventional flow behavior. The temperature coefficient of surface tension (TCST) is the coexistence of TCST (-) and TCST (+), leading to a novel flow pattern with combined inward-outward flows. Moreover, the anomalous flow exhibits observed phenomena such as the rotation of the major axis (RA) and center line shift (CLS) within the melt pool, showing more reasonable simulated melt pool dimensions when accounting for the sulfur effect. Additionally, the dilution model integrated with the unconventional flow pattern presents a more uniform concentration distribution compared to the conventional dilution. Finally, the simulated distribution of alloy elements is validated effectively by experimental data obtained from Energy Dispersive Spectrometer (EDS) analysis.

Study on the removal of fulvic acid in water by potassium ferrate-enhanced iron-manganese co-oxide film and its mechanism.

The previous studies have shown that iron-manganese co-oxide film (MeOx) could simultaneously remove ammonium, manganese ion and bisphenol A. In this study, the removal of fulvic acid (FA) was explored by adding potassium ferrate (K2FeO4) to heighten the catalytic activity of MeOx. After adding about 3.0mg/L potassium ferrate, the elimination efficiency of 7.0mg/L FA by the MeOx increased from 20 to 50%. The effects of temperature and ammonium on the elimination of FA were investigated. Higher temperature (above 22°C) and higher ammonium concentration (above 2.0mg/L) caused a decrease in FA removal. Most of FA combined with the ferric hydroxide colloid produced by K2FeO4 in water to form macromolecular groups, and they were subsequently absorbed and covered on the surface of MeOx. Scanning electron microscope showed that more viscous flocs appeared on the surface of MeOx, and the film thickness became thicker. Electron energy-dispersive spectrometer analysis revealed a notable increased in the C-O element ratio and a significant decreased in the Mn-Fe element ratio on the surface of MeOx. From Fourier transform infrared spectroscopy, the content of transition metal carbonyl compounds increased in the surface of MeOx. XPS analysis confirmed that the presence of Fe3O4, FeO, Mn2O3 and Mn3O4 along with functional group substances of FA attached on the surface of MeOx. The removal mechanism of FA was studied.

Enhancing La(III) biosorption and biomineralization with Micromonospora saelicesensis: Involvement of phosphorus and formation of monazite nano-minerals

The release of rare earth elements (REEs) from mining wastes and their applications has significant environmental implications, necessitating the development of effective prevention and reclamation strategies. The mobility of REEs in groundwater due to microorganisms has garnered considerable attention. In this study, a La(III) resistant actinobacterium, Micromonospora saelicesensis KLBMP 9669, was isolated from REE enrichment soil in GuiZhou, China, and evaluated for its ability to adsorb and biomineralize La(III). The findings demonstrated that M. saelicesensis KLBMP 9669 immobilized La(III) through the physical and chemical interactions, with immobilization being influenced by the initial La(III) concentration, biomass, and pH. The adsorption kinetics followed a pseudo-second-order rate model, and the adsorption isotherm conformed to the Langmuir model. La(III) adsorption capacity of this strain was 90 mg/g, and removal rate was 94 %. Scanning electron microscope (SEM) coupled with energy dispersive X-ray spectrometer (EDS) analysis revealed the coexistence of La(III) with C, N, O, and P. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) investigations further indicated that carboxyl, amino, carbonyl, and phosphate groups on the mycelial surface may participate in lanthanum adsorption. Transmission electron microscopy (TEM) revealed that La(III) accumulation throughout the M. saelicesensis KLBMP 9669, with some granular deposits on the mycelial surface. Selected area electron diffraction (SAED) confirmed the presence of LaPO4 crystals on the M. saelicesensis KLBMP 9669 biomass after a prolonged period of La(III) accumulation. This post-sorption nano-crystallization on the M. saelicesensis KLBMP 9669 mycelial surface is expected to play a crucial role in limiting the bioimmobilization of REEs in geological repositories.

Analysis of the materials and processes of hanging sculptures in Guanyin Hall

Changzhi Guanyin Hall, a folk temple from the Ming Dynasty, embodies the essence of the ‘unity of the three religions’ philosophy, centred around Guanyin Bodhisattva. Over 500 sculptures reside within a modest 70 m2 space, encompassing representations from Confucianism, Buddhism and Taoism. Ranging from a towering 2 m to a mere 10 cm, these sculptures depict an array of characters and mythological scenes, bestowing considerable importance upon the painted sculptures of Guanyin Hall. Varying degrees of deterioration have affected these sculptures due to the passage of time and suboptimal preservation conditions, highlighting the imperative need for meticulous restoration efforts. However, the absence of comprehensive analyses pertaining to the production process of Guanyin Hall sculptures has hindered the restoration groundwork. This study focuses on fallen hanging sculptures and debris, encompassing intact sculptures, clay fragments, wooden sticks, plant fibres, wires and pigments. Employing a series of techniques, including X-ray photography, microscopic analysis, mineral analysis (MLA), laser particle size testing, ion chromatography, X-ray fluorescence spectroscopy (XRF), X-ray diffractometer (XRD) and energy dispersive spectrometer (SEM–EDS) analysis, this research characterises the constituent materials used in crafting these artifacts. Instead of a full-body skeleton, the findings reveal that the small hanging sculpture is supported by delicate wires that hold specific areas, such as the arms and the gown hems. The hanging sculptures are made from a single type of clay and are reinforced with either mulberry bast or wheat straw fibres. A Pinaceae wood stick affixes the head to the body, and the sculpture is then suspended on the wall through nails inserted into the feet. The moulded clay undergoes a sequence of carving, drying and polishing and is coated with a white ash layer before receiving intricate painting. Mineral pigments, including cinnabar, red lead, iron red, cerussite, atacamite, brochantite and azurite, adorn the surface of the sculptures, with gold foil embellishing the golden elements. The intricate artisanry and multifaceted material composition of Guanyin Hall’s painted sculptures render them unparalleled artistic treasures, not solely within Shanxi but across the entire nation. Furthermore, this study establishes a dependable foundation for conservation and restoration endeavours.

Study on the performance of basalt fiber geopolymer concrete by freeze-thaw cycle coupled with sulfate erosion

In this research, double-blended materials such as fly ash and slag are used as binders, and basalt fibers (BF) are mixed in varying volume fractions (0.2%, 0.4%, 0.6%, 0.8%, and 1.0%) relative to the volume of concrete. Besides, sodium silicate (Na2SiO3) and sodium hydroxide (NaOH) served as activators. The study investigates the freeze-thaw resistance, microstructure, performance mechanism, and internal freeze-thaw damage distribution of basalt fiber geopolymer concrete (BFGPC) through freeze-thaw cycle tests coupled with sulfate attack, SEM, and energy dispersive spectrometer analyses. The results indicated that BFGPC possesses excellent freeze-thaw resistance, achieving a minimum frost-resisting grade of F200. Increasing the BF content significantly enhances the frost resistance of the concrete. The hydration products of BFGPC include C–(A)–S–H gel, C–S–H gel, and a minor amount of N–A–S–H gel, which contribute to its structural density and homogeneity. The high compressive strength of BFGPC (87.7 MPa) further contributes to its outstanding freeze-thaw durability.

Performance evaluation of waterborne epoxy emulsified asphalt micro-surfacing with microwave-activated waste rubber powder

As a solid renewable resource, waste rubber powder (R) applied in road engineering can help reduce the environmental pressure caused by "black pollution" and improve pavement performance. In this research, waste rubber powder was activated by microwave method, namely as MR. The content of 0%∼ 5% MR was added as a functional filler to the waterborne epoxy emulsified asphalt (WEA) micro-surfacing mixture, thereby obtaining the MRWEA micro-surfacing. Furthermore, pavement performance, durability and noise reduction property were evaluated and compared with those of WEA micro-surfacing adding non-activated R (RWEA micro-surfacing). Results show that the surface activity of MR has been enhanced effectively, and the surface hydrophobicity of MR is better than R through the contact angle test. These findings are also confirmed by Fourier transform infrared spectrometer (FTIR), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) analysis. Then, MRWEA micro-surfacing has good workability and cohesion due to the surface activity of MR. At the same dosage MR and R, 30 min, 60 min cohesion of MRWEA micro-surfacing mixture is greater than that of RWEA micro-surfacing mixture. Furthermore, MRWEA micro-surfacing with 3% MR has better wear resistance, rutting resistance, water resistance, durability and noise reduction properties than those of RWEA micro-surfacing with 3% R.

Morphological and structural properties of bismuth-nickel ferrite synthesized by a combined sol-gel method

In this paper, Bi x Ni1-x Fe2O4, (x = 0, 0.3, and 0.5), nanoparticles were synthesized by a sol–gel method, and the synthesized samples were calcination at 350 and 650o C for 3 h. The influence of Bi doping on morphological and structural properties was studied. The field emission scanning electron microscopy (FESEM) analysis showed all of the specimens contain a compact order of homogenous nanoparticles with a spherical form and polyhedral particles with an average size ranging from 36.305 nm to 27.554 nm at 350 and 650o C respectively. By studying the energy dispersive spectrometer analysis patterns, the existence of constituent elements, Ni, Bi, Fe, and O, was verified with a proportion very close to the stoichiometry of the chemical formula. The formation of a ferrite phase was confirmed by X-ray diffraction. An increase in the average crystallite and grain size has been observed with an increase in Bi doping. The Fourier Transform Infrared(FT-IR) studies were made in the frequency range 400-4000 cm-1 and observed two strong absorption peaks. The frequency band is found at 555 cm-1 whereas the lower frequency band is at 1338.5 cm-1. It is noticed that the two prominent absorption bands were slightly shifted towards the higher frequency side with the increase of Bi3+ ion concentration.

Anhydrous sol-gel synthesis of TiO2 nanoparticles: Evaluating their impact on protein interactions in biological systems

This study focused on the synthesis of anhydrous sol-gel synthesis of TiO2 nanoparticles using a hydrothermal route. The chemical properties of the synthesized TiO2 nanoparticles were confirmed through Fourier Transform Infrared Spectroscopy (FT-IR) and UV–Vis spectroscopy, highlighting their optical features. Additionally, Energy Dispersive X-ray Spectrometer (EDX) analysis revealed the high purity of the nanomaterial, while the Transmission Electron Microscope (TEM) displayed spherical particles ranging in size from ≥ 80 nm. Furthermore, X-ray diffraction analysis (XRD), Raman and HRTEM analyses indicated that the nanomaterial exhibits an anatase and rutile structure. When, Hen Egg-White Lysozyme (HEWL) incubated with TiO2 led to notable changes: reduced fluorescence indicating protein unfolding, increased light scattering showing protein aggregation, the presence of amyloid fibrils and hydrophobic regions, and reduced enzyme activity. FTIR spectroscopy revealed amyloid structure formation, while Dynamic Light Scattering confirmed the presence of larger protein oligomers. These findings highlight TiO2's adverse impact on HEWL structure and function, emphasizing the need for further research on nanoparticle toxicity in biological systems, particularly in biomedical applications.

Study on fabrication of force transducer based on carbon nano-flake balls

The purpose of this study was to fabricate a force sensor. A novel three-dimensional carbon-based material called a carbon nano-flake ball (CNFB) was used because it exhibits a large surface-area and high electrical conductivity. Moreover, CNFB can be easily fabricated using a one-step process via microwave plasma chemical vapor deposition. In the present study, two different methods, chemical and mechanical exfoliation, were used to fabricate the CNFB thin films. CNFEs were successfully synthesized on the silicon-based composite substrate. The substrate was constructed by the Si, SiO2, and Al2O3, where Al2O3 played the role of the substrate for the force sensor while SiO2 was the interface layer and was removed in the process by hydrogen fluoride (HF) solution to separate Al2O3 from Silicon. The experiments showed that using sol–gel catalyst coating as pretreatment precursor, results in a larger ball-size but lower deposition density of CNFB on Al2O3 substrate. By using mechanical exfoliation by polyimide (PI) tape, the CNFB grown on silicon substrate can be easily exfoliated from the substrate. PI/CNFB was successfully exfoliated from the substrate with a silver-grey color at the bottom of the CNFB which is likely to be silicon carbide (SiC) from the energy dispersive spectrometer analysis. The sheet resistance of PI/CNFB was 18.3 ± 1.0 Ω sq.−1 PI/CNFB exhibits a good force sensing performance with good stability after 10 times of loading-unloading cycles and a good sensitivity of 11.6 Ω g−1.

Corrosion Performance Analysis of Tubing Materials with Different Cr Contents in the CO2 Flooding Injection–Production Environment

In order to clarify the difference in corrosion performance between low Cr-containing (3Cr, 5Cr, and 9Cr) tubing material and carbon steel N80 in the Carbon dioxide (CO2) flooding injection and production environment and the range of adaptation, corrosion tests and analysis were carried out in simulated working conditions. In this paper, the electrochemical potentiodynamic testing technology and the weight loss method were used to comparatively analyze the corrosion performance and variation law of three types of tubing materials with different Cr contents in a simulated CO2 flooding-produced water environment under different partial pressure conditions. Additionally, scanning electron microscopy and Energy Dispersive Spectrometer (EDS) analysis were conducted to examine the surface corrosion morphology characteristics and elemental composition of material films under various conditions. The results indicate that the open circuit potentials of 3Cr, 5Cr, and carbon steel N80 were similar under the same experimental conditions. However, the open circuit potentials of 9Cr were relatively high and there was an obvious passivation zone in anodic polarization. Nevertheless, compared to that of 13Cr, the passivation state was unstable, and pitting corrosion continued to expand once it formed. This demonstrates that the corrosion resistance of the material can be effectively enhanced and a stable passivation state can be achieved in the anodic polarization region when the Cr content of the material reaches at least 13%. The service life of materials can be predicted based on their corrosion rate under high temperature and pressure simulation environments. We found that 9Cr materials exhibited good adaptability while 3Cr and 5Cr materials showed poor adaptability. Therefore, it was not recommended to use 3Cr and 5Cr materials. Therefore, 3Cr, 5Cr, and N80 materials will be used at lower partial pressure levels of CO2 (<0.2 MPa).

The Liquid Fraction of ZA27 Zinc Alloy from TLP Diffusion Bonding Affecting Mechanical Properties and Microstructural Characterizations of SSC-ADC12 Aluminum Alloy

This work investigated liquid fraction in ZA27 zinc alloy interlayered with SSC-ADC12 aluminum alloy workpieces for Transient Liquid Phase (TLP) diffusion bonding. The results clearly indicated that liquid fraction had a necessary influence on TLP diffusion bonding. In other words, the high liquid fraction and bonding time tends to produce excellent bond strength. The maximum bond strength at 27.21 MPa was from 100% liquid fraction and 90 min from bonding time. The hardness increased by approximately 23.36% comparing to SSC-ADC12 aluminum alloy and by 11.18% comparing to the ZA27 zinc alloy. The microstructure was homogeneous in the bond line and formed to MgZn2 and CuZn4 intermetallic compound under Scanning Electron Microscope. According to Energy Dispersive X-Ray Spectrometer analysis, Zn atoms had the ability to move about 4.381 mm from the bond line and the elements' uniform distribution.

Surface Characterization, Mechanical Properties, and Corrosion Behavior of Zn-Ni Alloy Coated Steel Using Electroplating-Hot-Dip Galvanizing

In this study, the processing of zinc-nickel alloys with an electroplated nickel layer as the first layer followed by hot-dip galvanizing on plain carbon steel (St37) is investigated. The effect of the nickel layer and the effect of the immersion time on the alloy layers of the coating obtained by this method are studied. In addition, some properties of the obtained coating, such as the overall thickness, hardness, surface uniformity, coating adhesion strength, and corrosion resistance, were investigated using the optical microscope, scanning electron microscopy, energy dispersive x-ray spectrometer analysis, and potentiostat. The results show that the 16-min immersion time is the optimum galvanizing time at which an alloy with a nickel content of 0.11 wt% is formed and that the overall thickness of the galvanized sheet, especially the alloy layers, decreases compared to the pure zinc sheet. In addition, a more ductile, corrosion-resistant, and smoother surface is obtained.