Revisiting Optical Reflectance from Au(111) Electrode Surfaces with Combined High-Energy Surface X-ray Diffraction

In this work, Yttria (Y2O3) was successfully doped into tetragonal 3mol% yttria stabilized Zirconia (3YSZ) by high energy-mechanical milling to synthesize 8mol% yttria stabilized Zirconia (8YSZ) used as an electrolyte for high temperature solid oxide fuel cells (HT-SOFC). This work aims to evaluate the densification and ionic conductivity of the sintered electrolytes at 1650°C. The bulk density was measured according to ASTM C373-17. The powder morphology and the microstructure of the sintered electrolytes were analyzed via Field Emission Scanning Electron Microscopy (FESEM). The chemical analysis was obtained with Energy-dispersive X-ray spectroscopy (EDS). Also, X-ray diffraction (XRD) was used to obtain structural information of the starting materials and the sintered electrolytes. The ionic conductivity was obtained through electrochemical impedance spectroscopy (EIS) in the air as a function of temperatures at a frequency range of 100(mHz)-100(kHz). It is found that the 3YSZ has a higher density than the 8YSZ. The impedance analysis showed that the ionic conductivity of the prepared 8YSZ at 800°C is0.906 (S.cm) and it was 0.214(S.cm) of the 3YSZ. Besides, 8YSZ has a lower activation energy 0.774(eV) than that of the 3YSZ 0.901(eV). Thus, the prepared 8YSZ can be nominated as an electrolyte for the HT-SOFC.

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Corrosion-induced microstructure degradation of copper in sulfide-containing simulated anoxic groundwater studied by synchrotron high-energy X-ray diffraction and ab-initio density functional theory calculation

Corrosion Science ◽

10.1016/j.corsci.2021.109390 ◽

2021 ◽

Vol 184 ◽

pp. 109390

Author(s):

Fan Zhang ◽

Cem Örnek ◽

Min Liu ◽

Timo Müller ◽

Ulrich Lienert ◽

...

Keyword(s):

Density Functional Theory ◽

Ab Initio ◽

Density Functional ◽

Density Functional Theory Calculation ◽

High Energy ◽

X Ray Diffraction ◽

Functional Theory ◽

X Ray ◽

Theory Calculation

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Estimating single-crystal elastic constants of polycrystalline β metastable titanium alloy: A Bayesian inference analysis based on high energy X-ray diffraction and micromechanical modeling

Acta Materialia ◽

10.1016/j.actamat.2021.116762 ◽

2021 ◽

pp. 116762

Author(s):

Ravi raj purohit PURUSHOTTAM RAJ PUROHIT ◽

Thiebaud RICHETON ◽

Stephane BERBENNI ◽

Lionel GERMAIN ◽

Nathalie GEY ◽

...

Keyword(s):

Titanium Alloy ◽

Bayesian Inference ◽

Single Crystal ◽

Elastic Constants ◽

High Energy ◽

Bayesian Inference Analysis ◽

Micromechanical Modeling ◽

X Ray Diffraction ◽

X Ray

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In-Situ High-Energy X-ray Diffraction Study of Austenite Decomposition During Rapid Cooling and Isothermal Holding in Two HSLA Steels

Metallurgical and Materials Transactions A ◽

10.1007/s11661-021-06192-x ◽

2021 ◽

Vol 52 (5) ◽

pp. 1812-1825

Author(s):

Sen Lin ◽

Ulrika Borggren ◽

Andreas Stark ◽

Annika Borgenstam ◽

Wangzhong Mu ◽

...

Keyword(s):

Isothermal Holding ◽

Weight Percent ◽

High Energy ◽

Decomposition Kinetics ◽

Bainitic Transformation ◽

Austenite Decomposition ◽

X Ray Diffraction ◽

Rapid Cooling ◽

X Ray

AbstractIn-situ high-energy X-ray diffraction experiments with high temporal resolution during rapid cooling (280 °C s−1) and isothermal heat treatments (at 450 °C, 500 °C, and 550 °C for 30 minutes) were performed to study austenite decomposition in two commercial high-strength low-alloy steels. The rapid phase transformations occurring in these types of steels are investigated for the first time in-situ, aiding a detailed analysis of the austenite decomposition kinetics. For the low hardenability steel with main composition Fe-0.08C-1.7Mn-0.403Si-0.303Cr in weight percent, austenite decomposition to polygonal ferrite and bainite occurs already during the initial cooling. However, for the high hardenability steel with main composition Fe-0.08C-1.79Mn-0.182Si-0.757Cr-0.094Mo in weight percent, the austenite decomposition kinetics is retarded, chiefly by the Mo addition, and therefore mainly bainitic transformation occurs during isothermal holding; the bainitic transformation rate at the isothermal holding is clearly enhanced by lowered temperature from 550 °C to 500 °C and 450 °C. During prolonged isothermal holding, carbide formation leads to decreased austenite carbon content and promotes continued bainitic ferrite formation. Moreover, at prolonged isothermal holding at higher temperatures some degenerate pearlite form.

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