scholarly journals Effect of the Boron Powder on Surface AISI W2 Steel: Experiments and Modelling

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Marco Antonio Doñu Ruiz ◽  
David Sánchez Huitron ◽  
Ernesto David Garcia Bustos ◽  
Víctor Jorge Cortés Suárez ◽  
Noé López Perrusquia
Keyword(s):  
Energy Dispersive Spectrometry ◽  
Single Layer ◽  
Boride Layer ◽  
Boron Diffusion ◽  
Mass Balance Equation ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Boron Powder ◽  
X Ray ◽  
Kinetics Of

The effect of boron powder on surface AISI W2 steel and growth kinetic of the boride layer is studied. Boron powder mixture was used in the powder pack boriding; this process was carried out in the temperature range from 1173 to 1273 K with exposure times ranging from 2 to 8 h. The presence of boride was confirmed by optical microscopy, X-ray diffraction, and the distribution of alloy elements in boride layers with energy-dispersive spectrometry using scanning electron microscopy. A mathematical model of the growth kinetics of the single layer was proposed and boron diffusion coefficient was determined by mass balance equation. The morphology of Fe2B layer was smooth and boron activation energy in W2 steel was estimated as 187.696 kJ·mol−1. The kinetic model was validated with two experimental conditions, a contour diagram describing the evolution of Fe2B layer as a function of time and temperature parameters for industrial application.

Investigation of Growth Kinetics of Fe2B Layers on AISI 1518 Steel by the Integral Method

2019 ◽  
Vol 38 (2019) ◽  
pp. 219-228
Author(s):  
M. Elias-Espinosa ◽  
M. Keddam ◽  
M. Ortiz-Domínguez ◽  
A. Arenas-Flores ◽  
J. Zuno-Silva ◽  
...  
Keyword(s):  
Alternative Model ◽  
Present Model ◽  
Boride Layer ◽  
Boron Diffusion ◽  
Mass Balance Equation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Temperature Range ◽  
Eds Analysis ◽  
Kinetics Of

AbstractThe AISI 1518 steel was pack-borided in the temperature range 1123–1273 K for a treatment ranging from 2 to 8 h. A compact single boride layer (Fe2B) was formed at the surface of the AISI 1518 steel using the mixture of powders composed of 20 % B4C, 10 % KBF4 and 70 % SiC. The following experimental techniques such as scanning electron microscopy coupled with EDS analysis and X-ray diffraction analysis were employed to characterize the pack-borided AISI 1518 steel. An alternative model, based on the integral mass balance equation, was used to estimate the boron diffusion coefficients in the Fe2B layers in the temperature range 1123–1273 K. Finally, the value of activation energy for boron diffusion in the AISI 1518 steel was estimated and compared with the literature data. Furthermore, the present model was validated by comparing the experimental value of Fe2B layer thickness, obtained at 1253 K for 2 h of treatment, with the predicted value.

scholarly journals Metallurgical Characterization and Kinetics of Borided 34CrNiMo6 Steel

2020 ◽  
Vol 20 (4) ◽  
pp. 38-48
Author(s):  
N. Ucar ◽  
M. Yigit ◽  
A. Calik
Keyword(s):  
Boride Layer ◽  
Carbon Steels ◽  
Boron Diffusion ◽  
X Ray Diffraction ◽  
Medium Carbon ◽  
X Ray ◽  
Medium Carbon Steels ◽  
Metallurgical Characterization ◽  
Kinetics Of ◽  
34Crnimo6 Steel

AbstractBoriding of 34CrNiMo6 steel was performed in a solid medium consisting of Ekabor-II powders at 1123, 1173 and 1223 K for 2, 4 and 6 h. Morphological and kinetic examinations of the boride layers were carried out by optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The thicknesses of the boride layers ranged from 22±2.3 to 145±4.1 depending on boriding temperature and time. The hardness of boride layer was about 1857 HV0.1 after boriding for 6 h at 1223 K, while the hardness of the substrate was only around 238 HV0.1. Growth rate constants were found to be between 1.2×10−13 – 9.8×10−13 m2/s depending on temperature. The activation energy for boron diffusion was estimated as 239.4±8.6 kJ mol−1. This value was comparable to the activation energies reported for medium carbon steels in the literature.

Study and Properties of a Steel Microalloyed Hardened Superficially

2015 ◽  
Vol 365 ◽  
pp. 122-127 ◽  
Author(s):  
N. López-Perrusquia ◽  
M.A. Doñu Ruiz ◽  
C. R. Torres San-Miguel ◽  
M. Flores-Báez ◽  
I. Flores-Báez
Keyword(s):  
Growth Process ◽  
Energy Dispersive Spectrometry ◽  
Boride Layer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffusion Controlled ◽  
Boriding Process ◽  
Kinetics Of ◽  
Over Time ◽  
Scanning Electron

In this study, we present a boronizing treatment on a steel microalloy that was performed according to dehydrated paste-pack boriding. The temperatures conducted were at 1173, 1223 and 1273 K; at various exposure times of 1, 3, 6 and 9 h. As a result of the boriding process, diffusion-controlled growth of the FeB/Fe2B layers was obtained at the surface of the micro-alloy steel, and the kinetics of the growth process changed parabolically over time. The results of these examination properties of the boride layer as revealed by Optical Microscopy (OP) showed the morphology of the boride layer as a saw-tooth with a thickness ranging from 33 μm to 220 μm depending on the boronizing time. The analysis of Scanning Electron Microscopy (SEM-EDS); showed a distribution of the alloying elements that were detected by Energy Dispersive Spectrometry. The X-ray diffraction (XRD) technique indicated that the surface was a mixture of FeB and Fe2B borides. The evaluation of adhesion of the layers was determined by the technique of Rockwell-C hardness. Young’s modulus and hardness of the layer were evaluated by a nanoindentation technique with a load of 250 mN. The paste dehydrate boriding of micro-alloy reveal a change of properties on the surface; also the coatings FeB and Fe2B, to make a sacrificial function in the steels micro alloyed as widely used in pipelines transporting oil.

scholarly journals Cálculo de la energía de activación de la difusión de boro en la capa de Fe2B en la borurización por empaquetamiento de los aceros SAE 1050 y DIN UC1

2019 ◽  
pp. 8-17
Author(s):  
Merced Martínez-Vázquez ◽  
Marissa Vargas-Ramírez ◽  
Lourdes Cortés-Campos ◽  
Juan Gregorio Hortelano-Capetillo
Keyword(s):  
Activation Energy ◽  
Chemical Composition ◽  
Single Phase ◽  
Microscopic Analysis ◽  
Type Equation ◽  
Boron Diffusion ◽  
Mass Balance Equation ◽  
X Ray Diffraction ◽  
Iron Boride ◽  
X Ray

The layer of iron boride (Fe2B) was formed on the surface of two steels, SAE 1005 and DIN UC1; after being subjected a treatment by packaging, and it was used to study the effect of the chemical composition on the thickness of the layer, the growth kinetics and the activation energy for boron diffusion. The mass balance equation and the parabolic growth law were used at the Fe2B/substrate interface, considering that the layer begins to grow after an incubation time (t0). The microscopic analysis revealed in the iron boride its form irregular, type saw teeth, in both steels. The present phases were identified by X-Ray diffraction, corroborating the presence of a single-phase Fe2B layer. An Arrhenius-type equation was used to correlate the layer thickness with the activation energy, which for this study was determined in 132.3 and 143.9 kJ mol-1 for SAE1005 and DIN UC1 steels, respectively.

scholarly journals In situ probing of the crystallization kinetics of rr-P3HT on single layer graphene as a function of temperature

2017 ◽  
Vol 19 (12) ◽  
pp. 8496-8503 ◽  
Author(s):  
Nicolas Boulanger ◽  
Victor Yu ◽  
Michael Hilke ◽  
Michael F. Toney ◽  
David R. Barbero
Keyword(s):  
Diffraction Analysis ◽  
Crystallization Kinetics ◽  
Single Layer ◽  
Single Layer Graphene ◽  
X Ray Diffraction ◽  
X Ray ◽  
Layer Graphene ◽  
Kinetics Of

In situ X-ray diffraction analysis of P3HT films during cooling down on both Si and G.

scholarly journals Boriding kinetics of Fe2B layers formed on AISI 1045 steel

2014 ◽  
Vol 50 (2) ◽  
pp. 101-107 ◽  
Author(s):  
J. Zuno-Silva ◽  
M. Ortiz-Domínguez ◽  
M. Keddam ◽  
M. Elias-Espinosa ◽  
O. Damián-Mejía ◽  
...  
Keyword(s):  
Diffusion Model ◽  
Diffusion Coefficients ◽  
Mass Conservation ◽  
Boron Diffusion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel ◽  
Kinetics Of

In the present work, a diffusion model was suggested to study the growth kinetics of Fe2B layers grown on the AISI 1045 steel by the pack-boriding treatment. The generated boride layers were analyzed by optical microscopy and X-ray diffraction analysis. The applied diffusion model is based on the principle of mass conservation at the (Fe2B/ substrate) interface. It was used to estimate the boron diffusion coefficients of Fe2B in the temperature range of 1123-1273 K. A validation of the model was also made by comparing the experimental Fe2B layer thickness obtained at 1253 K for 5 h of treatment with the predicted value. Basing on our experimental results, the boron activation energy was estimated as 180 kJ mol-1 for the AISI 1045 steel.

scholarly journals Stable and Metastable Phase Equilibria Involving the Cu6Sn5 Intermetallic

2021 ◽  
Author(s):  
A. Leineweber ◽  
M. Löffler ◽  
S. Martin
Keyword(s):  
Phase Equilibria ◽  
Electron Backscatter Diffraction ◽  
Metastable Phase ◽  
Stable Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Ordered Phases ◽  
Backscatter Diffraction ◽  
Kinetics Of

Abstract Cu6Sn5 intermetallic occurs in the form of differently ordered phases η, η′ and η′′. In solder joints, this intermetallic can undergo changes in composition and the state of order without or while interacting with excess Cu and excess Sn in the system, potentially giving rise to detrimental changes in the mechanical properties of the solder. In order to study such processes in fundamental detail and to get more detailed information about the metastable and stable phase equilibria, model alloys consisting of Cu3Sn + Cu6Sn5 as well as Cu6Sn5 + Sn-rich melt were heat treated. Powder x-ray diffraction and scanning electron microscopy supplemented by electron backscatter diffraction were used to investigate the structural and microstructural changes. It was shown that Sn-poor η can increase its Sn content by Cu3Sn precipitation at grain boundaries or by uptake of Sn from the Sn-rich melt. From the kinetics of the former process at 513 K and the grain size of the η phase, we obtained an interdiffusion coefficient in η of (3 ± 1) × 10−16 m2 s−1. Comparison of this value with literature data implies that this value reflects pure volume (inter)diffusion, while Cu6Sn5 growth at low temperature is typically strongly influenced by grain-boundary diffusion. These investigations also confirm that η′′ forming below a composition-dependent transus temperature gradually enriches in Sn content, confirming that Sn-poor η′′ is metastable against decomposition into Cu3Sn and more Sn-rich η or (at lower temperatures) η′. Graphic Abstract

scholarly journals Zeolite NaP1 Functionalization for the Sorption of Metal Complexes with Biodegradable N-(1,2-dicarboxyethyl)-D,L-aspartic Acid

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2518
Author(s):  
Dorota Kołodyńska ◽  
Yongming Ju ◽  
Małgorzata Franus ◽  
Wojciech Franus
Keyword(s):  
Experimental Data ◽  
Aspartic Acid ◽  
Ph Value ◽  
Complexing Agents ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Modified Zeolite ◽  
X Ray ◽  
Slow Release Fertilizers ◽  
Pseudo Second Order

The possibility of application of chitosan-modified zeolite as sorbent for Cu(II), Zn(II), Mn(II), and Fe(III) ions and their mixtures in the presence of N-(1,2-dicarboxyethyl)-D,L-aspartic acid, IDHA) under different experimental conditions were investigated. Chitosan-modified zeolite belongs to the group of biodegradable complexing agents used in fertilizer production. NaP1CS as a carrier forms a barrier to the spontaneous release of the fertilizer into soil. The obtained materials were characterized by Fourier transform infrared spectroscopy (FTIR); surface area determination (ASAP); scanning electron microscopy (SEM-EDS); X-ray fluorescence (XRF); X-ray diffraction (XRD); and carbon, hydrogen, and nitrogen (CHN), as well as thermogravimetric (TGA) methods. The concentrations of Cu(II), Zn(II), Mn(II), and Fe(III) complexes with IDHA varied from 5–20 mg/dm3 for Cu(II), 10–40 mg/dm3 for Fe(III), 20–80 mg/dm3 for Mn(II), and 10–40 mg/dm3 for Zn(II), respectively; pH value (3–6), time (1–120 min), and temperature (293–333 K) on the sorption efficiency were tested. The Langmuir, Freundlich, Dubinin–Radushkevich, and Temkin adsorption models were applied to describe experimental data. The pH 5 proved to be appropriate for adsorption. The pseudo-second order and Langmuir models were consistent with the experimental data. The thermodynamic parameters indicate that adsorption is spontaneous and endothermic. The highest desorption percentage was achieved using the HCl solution, therefore, proving that method can be used to design slow-release fertilizers.

Study on Adsorption of Crosslinked Starch Microspheres towards Heavy Metal Ions

2013 ◽  
Vol 834-836 ◽  
pp. 531-535
Author(s):  
Li Yan Yang ◽  
Yi Hui Guo ◽  
Li Li Yu ◽  
Jing You
Keyword(s):  
Metal Ions ◽  
Reversed Phase ◽  
Adsorption Rate ◽  
X Ray Diffraction ◽  
Adsorption Selectivity ◽  
X Ray ◽  
Starch Microsphere ◽  
Other Substances ◽  
Effects Of Media ◽  
Kinetics Of

A type of cross-linking starch microsphere (CSMs) has been synthesized via reversed phase suspension method. Crosslinked starch microsphere has good adsorption performance to metal ions in water. The adsorption kinetics of Co (II) on the CSMs, selectivity of adsorption CSMs towards Co (II),Cu (II),Pb (II),Cd (II) and adsorption effects of media towards Co (II) were investigated. The CSMs and its adsorption product were comparatively characterized by X-ray diffraction (XRD). The results showed that The adsorption rate is mainly controlled by liquid film diffusion, and the constant of adsorption rate is 0.0686min-1 at 308K. The crystal structure of the CSMs decreased greatly after the incorporation of Co (II). Co (II) has better adsorption selectivity on CSMs. Ions coexist and other substances in the solution have certain impact on adsorption. Those data are helpful for treatment of the wastewater containing heavy ions.

Efficient adsorption of chlorpyrifos onto modified activated carbon by gamma irradiation; a plausible adsorption mechanism

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mohamed S. Yahia ◽  
Ahmed S. Elzaref ◽  
Magdy B. Awad ◽  
Ahmed M. Tony ◽  
Ahmed S. Elfeky
Keyword(s):  
Gamma Irradiation ◽  
Area Measurement ◽  
Maximum Adsorption Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
Pseudo Second Order ◽  
Ft Ir ◽  
Pseudo First Order ◽  
Kinetics Of

Abstract Commercial Granulated Active Carbon (GAC) has been modified using 10 Gy dose Gamma irradiation (GAC10 Gy) for increasing its ability of air purification. Both, the raw and treated samples were applied for removing Chlorpyrifos pesticide (CPF) from ambient midair. Physicochemical properties of the two materials were characterized by Fourier Transform Infrared (FT-IR) and Raman spectroscopy. The phase formation and microstructure were monitored using X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), supported with Energy-Dispersive X-ray (EDX). The Surface area measurement was detected using BET particle size prosometry. Obtained outcomes showed that, the maximum adsorption capacity, given by Langmuir equations, was greatly increased from 172.712 to 272.480 mg/g for GAC and GAC10 Gy, respectively, with high selectivity. The overall removal efficiency of GAC10 Gy was notably comparable to that of the original GAC-sorbent. The present study indicated that, gamma irradiation could be a promising technique for treating GAC and turned it more active in eliminating the pesticides pollutants from surrounding air. The data of equilibrium has been analyzed by Langmuir and Freundlich models, that were considerably better suited for the investigated materials than other models. The process kinetics of CPF adsorbed onto both tested carbon versions were found to obey the pseudo first order at all concentrations with an exception at 70 mg/l using GAC, where, the spontaneous exothermic adsorption of Chlorpyrifos is a strong function for the pseudo-first order (PFO) and pseudo second order (PSO) kinetics.

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