Diffusion of Refractory Elements in Ternary Iron Alloys

2008 ◽  
Vol 273-276 ◽  
pp. 746-751
Author(s):  
Kouji Yamashita ◽  
Tomonori Kunieda ◽  
Koutarou Takeda ◽  
Yoshinori Murata ◽  
Toshiyuki Koyama ◽  
...  
Keyword(s):  
Ternary System ◽  
Interdiffusion Coefficient ◽  
Iron Alloys ◽  
Experimental Results ◽  
Diffusion System ◽  
Ternary Alloys ◽  
Attractive Interaction ◽  
Refractory Elements ◽  
The Cross ◽  
Interdiffusion Coefficients

Interdiffusion coefficients of the refractory elements in Fe-W-Re and Fe-Cr-X (X=Mo, W) ternary alloys have been measured on the basis of the modified Boltzmann-Matano method for ternary system. Both the cross interdiffusion coefficients, Fe ReW ~D and Fe WRe ~D were negative in Fe-W-Re ternary alloys. This result indicates that attractive interaction exists between W and Re atoms in iron alloys [1]. This is consistent with our previous experimental results that Re suppresses W diffusion in Fe-15Cr alloy [1]. In addition, the value of cross interdiffusion coefficient Fe CrW ~D was positive in Fe-Cr-W diffusion system, whereas Fe MoCr ~D was negative in Fe-Cr-Mo diffusion system.

Diffusion of Refractory Elements in Ni—X—Y (X, Y: Co, Re, Ru, W) Ternary Alloys

2008 ◽  
Vol 273-276 ◽  
pp. 572-576
Author(s):  
Shingo Sakurai ◽  
Efendi Mabruri ◽  
Yoshinori Murata ◽  
Toshiyuki Koyama ◽  
Masahiko Morinaga
Keyword(s):  
Interdiffusion Coefficient ◽  
Ternary Systems ◽  
Activation Energies ◽  
Alloy Design ◽  
Ternary Alloys ◽  
Refractory Elements ◽  
Series Of Experiments ◽  
The Cross ◽  
Interdiffusion Coefficients ◽  
Thermodynamic Interaction

Ni-based superalloys are strengthed by refractory elements such as Re, Ru and W [1]. Thus, the information on the interdiffusion coefficient as well as the thermodynamic interaction between the refractory elements is important for the future alloy design. In this study, interdiffusion coefficients of the refractory elements in Ni-X-Y (X, Y=Co, Re, Ru, W) ternary systems were estimated by a series of experiments. In the all systems studied in the present works, the main interdiffusion coefficients were much larger than the cross interdiffusion coefficients. In some systems, two cross interdiffuion coefficients had opposite signs each other. For example, in Ni-Co-Ru system, the main interdiffusion coefficients are 2.7 10 14 ~ Ru = × − CoCo D and 15 6.8 10 ~ Ru = × − RuRu D , while the cross interdiffusion coefficients are 16 6.6 10 ~ Ru = − × − CoRu D and 16 8.9 10 ~ Ru = × − RuCo D at 1523K. In Ni-Co-Ru and Ni-Re-Co systems, the activation energies and frequency factors for two main interdiffusion coefficients. For example, Q (kJ ) Co = 268 , 5 ( 2 1 ) 0( ) 4.4 10 D = × − m s − Co , 3 ( 2 1 ) 0( ) 2.9 10 D = × − m s − Ru in Ni-Co-Ru system.

Diffusion and Interaction of W and Re in Fe-Cr Alloys

2006 ◽  
Vol 258-260 ◽  
pp. 231-236 ◽  
Author(s):  
Yoshinori Murata ◽  
Tomonori Kunieda ◽  
Kouji Yamashita ◽  
Toshiyuki Koyama ◽  
Effendi ◽  
...  
Keyword(s):  
Ternary System ◽  
Base Alloy ◽  
Ternary Alloys ◽  
Ferritic Steels ◽  
Microstructural Stability ◽  
Alloying Effect ◽  
Refractory Elements ◽  
Basic Understanding ◽  
Heat Resistant Steels ◽  
Interdiffusion Coefficients

The diffusivity of refractory elements in heat resistant steels is crucial for the basic understanding of the microstructural stability during creep. The purposes of this study are to estimate the diffusivity in Fe-Cr alloys as a base alloy for the bcc matrix phase in high Cr ferritic steels and also to investigate the alloying effect of Re on the W diffusivity in them. Fe-15Cr and Fe-20Cr binary alloys, Fe-15Cr-5Re, Fe-15Cr-5W, Fe-20Cr-5Re ternary alloys [mol%] were used in this study. On the basis of the modified ternary Boltzmann-Matano method, the interdiffusion coefficients were obtained in Fe-Cr-Re ternary system. The apparent interdiffusion coefficient for the Re-doped Fe-Cr-W alloy was about one fifth of that for the Re-free alloy. It is concluded that the existence of Re retarded significantly the W diffusion in Fe-15mol%Cr based alloy. This is probably the main reason why a small amount of Re addition suppress the microstructural evolution of W containing high Cr ferritic steels.

Cross Interdiffusion Coefficients in Nickel- and Iron-Based Ternary Alloys

2008 ◽  
Vol 273-276 ◽  
pp. 419-424 ◽  
Author(s):  
Yoshinori Murata ◽  
Shingo Sakurai ◽  
Efendi Mabruri ◽  
Toshiyuki Koyama ◽  
Masahiko Morinaga
Keyword(s):  
Ternary System ◽  
Physical Meaning ◽  
Opposite Sign ◽  
Ternary Alloys ◽  
Atomic Diffusion ◽  
Ternary Diffusion ◽  
Series Of Experiments ◽  
The Cross ◽  
Interdiffusion Coefficients ◽  
The Relationship

It is known that two main interdiffusion coefficients, ık Dii and ık Djj , as well as two cross interdiffusion coefficients, ık Dij and ık Dji , are necessary for understanding the atomic diffusion for ternary system. Here, k is the host element of ternary system, and i and j are solute elements. These four interdiffusion coefficients are obtained from a series of experiments using two kinds of ternary diffusion couples. In general, it is believed that ık Dij and ık Dji indicate the same sign to each other, but there are a lot of experimental data showing that ık Dij and ık Dji indicate opposite sign [1]. In such a case, the physical meaning of the cross interdiffusion coefficient has not always been understood thoroughly. The purposes of this study are to measure the interdiffusion coefficients by a series of experiments and to elucidate the physical meaning of the two cross interdiffusion coefficients on the basis of the consideration about the relationship between the thermodynamic functions and the cross interdiffusion coefficients. It is concluded that ık Dij exhibits the opposite sign to ık Dji without contradicting the Onsarger’s reciprocity theorem when the ( 2 2 ) c j ∂ G ∂c shows the opposite sign to ( 2 2 ) c i ∂ G ∂c . Here, c G is Gibbs free energy of the ternary system.

scholarly journals InfPolyn, a Nonparametric Bayesian Characterization for Composition-Dependent Interdiffusion Coefficients

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3635
Author(s):  
Wei-W. Xing ◽  
Ming Cheng ◽  
Kaiming Cheng ◽  
Wei Zhang ◽  
Peng Wang
Keyword(s):  
Interdiffusion Coefficient ◽  
Diffusion Equations ◽  
Numerical Inversion ◽  
Extended Model ◽  
Parametric Form ◽  
Physical Processes ◽  
Large Margin ◽  
Statistical Framework ◽  
Fitting Method ◽  
Interdiffusion Coefficients

Composition-dependent interdiffusion coefficients are key parameters in many physical processes. However, finding such coefficients for a system with few components is challenging due to the underdetermination of the governing diffusion equations, the lack of data in practice, and the unknown parametric form of the interdiffusion coefficients. In this work, we propose InfPolyn, Infinite Polynomial, a novel statistical framework to characterize the component-dependent interdiffusion coefficients. Our model is a generalization of the commonly used polynomial fitting method with extended model capacity and flexibility and it is combined with the numerical inversion-based Boltzmann–Matano method for the interdiffusion coefficient estimations. We assess InfPolyn on ternary and quaternary systems with predefined polynomial, exponential, and sinusoidal interdiffusion coefficients. The experiments show that InfPolyn outperforms the competitors, the SOTA numerical inversion-based Boltzmann–Matano methods, with a large margin in terms of relative error (10x more accurate). Its performance is also consistent and stable, whereas the number of samples required remains small.

The influence of the nuclear and atomic form factors on the muon bremsstrahlung cross section

1968 ◽  
Vol 46 (10) ◽  
pp. S377-S380 ◽  
Author(s):  
A. A. Petrukhin ◽  
V. V. Shestakov
Keyword(s):  
Form Factor ◽  
Cross Section ◽  
Born Approximation ◽  
Form Factors ◽  
Experimental Results ◽  
Simple Analytical Expression ◽  
Nuclear Form Factor ◽  
The Cross ◽  
Atomic Electrons ◽  
Bremsstrahlung Process

The cross section for the muon bremsstrahlung process is calculated as a function of the nuclear form factor in the Born approximation following the Bethe and Heitler theory. The influence of the nuclear form factor is greater than that taken by Christy and Kusaka. The simple analytical expression for the effect of the screening of the atomic electrons is found. The influence of a decrease in the cross section upon the interpretation of some experimental results is estimated.

scholarly journals The Addition of N-Butanol in Ethanol-Isooctane Mixture to Reduce Vapor Pressure of Oxygenated-Gasoline Blend

2017 ◽  
Vol 17 (3) ◽  
pp. 500 ◽  
Author(s):  
Rendra Panca Anugraha ◽  
Zul Akbar Andi Picunang ◽  
Annas Wiguno ◽  
Rizky Tetrisyanda ◽  
Kuswandi Kuswandi ◽  
...  
Keyword(s):  
Experimental Data ◽  
Ternary System ◽  
Vapor Pressure ◽  
Binary Systems ◽  
Experimental Results ◽  
Ideal Solution ◽  
Positive Deviation ◽  
Relative Deviation ◽  
Wilson Model ◽  
Binary Parameter

In this work, vapor pressure of binary systems for isooctane + ethanol, isooctane + n-butanol and ethanol + n-butanol and ternary system for isooctane + ethanol + n-butanol were measured in the temperature range from 313.15 to 318.15 K using the inclined ebulliometer. The experimental results showed that the existence of n-butanol in isooctane decreases the vapor pressure of mixture, while increasing n-butanol fraction in ternary isooctane-ethanol-n-butanol mixture decreased vapor pressure of mixture. Experimental data for binary systems studied were correlated with Wilson, NRTL and UNIQUAC models with average relative deviation (ARD) of 3.5%. The optimized binary parameter pairs obtained in this work were used to estimate the ternary system. The Wilson model gave the best performance for estimation of ternary system with ARD of 5.4%. All systems studied showed non-ideal solution with positive deviation from Raoult’s law.

Behavior of porosity in billet during rolling process of rail

2019 ◽  
Vol 116 (6) ◽  
pp. 607 ◽  
Author(s):  
Rong Cheng ◽  
Jiongming Zhang ◽  
Liangjin Zhang ◽  
Haitao Ma
Keyword(s):  
Simulation Model ◽  
Cross Section ◽  
Rolling Process ◽  
Experimental Results ◽  
Short Cracks ◽  
Industrial Experiments ◽  
Isosceles Trapezoid ◽  
The Cross

Unlike traditional rolling processes, reduction of rolling process of rail is along two vertical directions and the broadening of rolled piece is controlled. In this study, industrial experiments and a simulation model of the rolling process of rail were conducted to investigate the behaviors of porosities in billet during the rolling process of rail. The experimental and simulated results revealed that porosities moved toward the center on the cross section of the rolled piece and the porosities region reduced from a rectangle with the size (76.7 × 93.3 mm) to an isosceles trapezoid with the size {(12.8 + 18.5 mm) × 47.2 mm} during the rolling process of rail. The shapes of the porosities changed from circles with the diameters smaller than 6 mm to short cracks with the lengths shorter than 10 mm on the cross section. The two vertical reduction directions and the controlled broadening of rolled piece both counted against the closure of porosity. The simulated results were mostly in agreement with the experimental results.

scholarly journals Interdiffusion of Refractory Elements in Fe-Cr-X (X-Mo, W) and Fe-Mo-W Ternary Iron Alloys

2008 ◽  
Vol 49 (3) ◽  
pp. 479-483 ◽  
Author(s):  
Koutarou Takeda ◽  
Kouji Yamashita ◽  
Yoshinori Murata ◽  
Toshiyuki Koyama ◽  
Masahiko Morinaga
Keyword(s):  
Iron Alloys ◽  
Refractory Elements

scholarly journals Enhancement of Impingement Heat Transfer With the Crossflow Normal to Ribs and Pins Between Each Row of Holes

2018 ◽  
Author(s):  
Abubakar M. El-Jummah ◽  
Gordon E. Andrews ◽  
John E. J. Staggs
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Pressure Loss ◽  
Cross Flow ◽  
Experimental Results ◽  
Hole Density ◽  
Impingement Heat Transfer ◽  
The Cross ◽  
Flow Maldistribution

Impingement heat transfer investigations with obstacle (fins) on the target surface were carried out with the obstacles aligned normal to the cross-flow. Conjugate heat transfer (CHT) computational fluid dynamics (CFD) analysis were used for the geometries previously been investigated experimentally. A 10 × 10 row of impingement jet holes or hole density, n, of 4306 m−2 with ten rows of holes in the cross-flow direction was used. The impingement hole pitch X to diameter D, X/D, and gap Z to diameter, Z/D, ratios were kept constant at 4.66 and 3.06 for X, D and Z of 15.24, 3.27 and 10.00 mm, respectively. Nimonic 75 test walls were used with a thickness of 6.35 mm. Two different shaped obstacles of the same flow blockage were investigated: a continuous rectangular ribbed wall of 4.5 mm height, H, and 3.0 mm thick and 8 mm high rectangular pin-fins that were 8.6 mm wide and 3.0 mm thick. The obstacles were equally spaced on the centre-line between each row of impingement jets and aligned normal to the cross-flow. The two obstacles had height to diameter ratios, H/D, of 1.38 and 2.45, respectively. Comparison of the predictions and experimental results were made for the flow pressure loss, ΔP/P, and the surface average heat transfer coefficient (HTC), h. The computations were carried out for air coolant mass flux, G, of 1.08, 1.48 and 1.94 kg/sm2bar. The pressure loss and surface average HTC for all the predicted G showed reasonable agreement with the experimental results, but the predictions for surface averaged h were below the measured values by 5–10%. The predictions showed that the main effect of the ribs and pins was to increase the pressure loss, which led to an increased flow maldistribution between the ten rows of holes. This led to lower heat transfer over the first 5 holes and higher heat transfer over the last 3 holes and the net result was little benefit of either obstacle relative to a smooth wall. The results were significantly worse than the same obstacles aligned for co-flow, where the flow maldistribution changes were lower and there was a net benefit of the obstacles on the surface averaged heat transfer coefficient.

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