Rapid screening alloying elements for improved corrosion resistance on the Mg (0001) surface using first principles calculations

2021 ◽  
Author(s):  
Chi Zhang ◽  
Junsheng Wang ◽  
Xin Li ◽  
Shuo Wang ◽  
Shijie Zhu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Anodic Dissolution ◽  
First Principles ◽  
Mg Alloys ◽  
Alloying Elements ◽  
Rapid Screening ◽  
First Principles Calculations ◽  
The Poor

The poor corrosion resistance of Mg alloys is a major challenge for their applications. The corrosion of Mg alloys is mainly controlled by the anodic dissolution of Mg and the...

Computational and Experimental Insights into the Role of Acidic Molecules on the Corrosion Behavior on 7A46 Aluminum Alloy

2021 ◽  
Vol 21 (4) ◽  
pp. 2221-2233
Author(s):  
Yaru Liu ◽  
Qinglin Pan ◽  
Xiangdong Wang ◽  
Ye Ji ◽  
Qicheng Liu ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Aluminum Alloy ◽  
Corrosion Behavior ◽  
First Principles ◽  
First Principles Calculations ◽  
Corrosive Media ◽  
Corrosion Depth ◽  
Corrosion Mechanisms ◽  
Nanoscale Level

The corrosion mechanisms for different corrosive media on the aged 7A46 aluminum alloy were systematically investigated at nanoscale level. The combination of empirical intergranular and exfoliation corrosion behavior was employed, and coupled with first-principles calculations. Results revealed that the dispersed distribution of matrix precipitates (MPs) leads to the enhancement of the corrosion resistance pre-ageing (PA) followed by double-ageing (PA-DA) alloy. The deepest corrosion depth of PA-DA alloy was in hydrochloric acid, and the calculation result demonstrates that the passivation effect in combination with the accumulation of corrosion products in nitric acid protect the PA-DA alloy from further corrosion.

Effect of Platinum Elements Additions on the Active Dissolution of Plastic Chromium in Sulfuric Acid

CORROSION ◽  
1984 ◽  
Vol 40 (3) ◽  
pp. 134-138 ◽  
Author(s):  
N. D. Tomashov ◽  
G. P. Chernova ◽  
E. N. Ustinsky
Keyword(s):  
Corrosion Resistance ◽  
Sulfuric Acid ◽  
Anodic Dissolution ◽  
Cathodic Polarization ◽  
Active State ◽  
Alloying Elements ◽  
Active Dissolution ◽  
Alloying Additions ◽  
Blocking Mechanism

Abstract Alloys based on plastic chromium with 0.1 to 0.4 mass % Ru, Pd, Ir, or Pt were investigated in 40% sulfuric acid in active state under cathodic polarization (−0.175 V). All of the studied additions of alloying elements are responsible for the reduced anodic dissolution of chromium. The corrosion resistance of alloys depends on the concentration and nature of the alloying additions. Two mechanisms decelerating the active dissolution of the cathode-modified chromium have been established, i.e., blocking mechanism (cathodic component atoms block the active points in the lattice) and screening mechanism (cathodic component, while getting crystallized on the surface, partly screens the latter).

[P6] Effects of alloying elements on elastic properties of Al by first-principles calculations

Calphad ◽  
2015 ◽  
Vol 51 ◽  
pp. 372-373
Author(s):  
Jiong Wang ◽  
Yong Du ◽  
Shun-Li Shang ◽  
Zi-Kui Liu ◽  
Yiwei Li
Keyword(s):  
Elastic Properties ◽  
First Principles ◽  
Alloying Elements ◽  
First Principles Calculations

Effect of Alloying Elements on the Elastic Properties of γ-Ni and γ'-Ni3Al from First-principles Calculations

2009 ◽  
Vol 1224 ◽  
Author(s):  
Yunjiang Wang ◽  
Chongyu Wang
Keyword(s):  
Elastic Properties ◽  
First Principles ◽  
Electronic Structures ◽  
Elastic Moduli ◽  
Lattice Misfit ◽  
Alloying Elements ◽  
First Principles Calculations ◽  
Strengthening Mechanisms ◽  
Two Phases ◽  
Effect Of Alloying

AbstractThe effect of alloying elements Ta, Mo, W, Cr, Re, Ru, Co, and Ir on the elastic properties of both γ-Ni and γ′-Ni3Al is studied by first-principles method. Results for lattice properties, elastic moduli and the ductile/brittle behaviors are all presented. Our calculated values agree well with the existing experimental observations. Results show all the additions decrease the lattice misfit between and γ′ phases. Different alloying elements are found to have different effect on the elastic moduli of γ-Ni. Whereas all the alloying elements slightly increase the moduli of γ′-Ni3Al expect Co. Both of the two phases are becoming more brittle with alloying elements, but Co is excepted. The electronic structures of γ′ phase alloyed with different elements are provided as example to elucidate the different strengthening mechanisms.

Grain Refining Behavior of Zr, Al2Y and Al4C3 Particles in Magnesium Alloys by the First-Principles Calculations

2015 ◽  
Vol 816 ◽  
pp. 370-374
Author(s):  
Jun Ling Pan ◽  
Qiu Ming Peng ◽  
Jian Xin Guo ◽  
Hui Li
Keyword(s):  
Mechanical Properties ◽  
Structural Optimization ◽  
Magnesium Alloys ◽  
Density Of States ◽  
Adsorption Energy ◽  
First Principles ◽  
Adsorption Process ◽  
Mg Alloys ◽  
Grain Refining ◽  
First Principles Calculations

Grain refining is one of the most important issues in the applications of Mg alloys, which directly determines mechanical properties and deformability. Therefore the understanding of grain refining mechanism during solidification will be benefit to develop new grain refiners. Herein refining role was elucidated by the first principles calculations based on adsorption behavior of a Mg atom on the closest-packed planes of grain refiners (Zr (001), Al2Y(311) and Al4C3(102)). Taking into account different sites, the site with the maximum adsorption energy value generally corresponded to the most possible location. The adsorption energy results show that the possible refining turn follows Al4C3(102)>Zr (001)>Al2Y(311). Meanwhile, the structural optimization confirmed that the Mg atom connected with two C atoms on the top of zig-zag plane of Al4C3(102), three Zr atoms at the hcp position on Zr (001), and two Y atoms and one Al atom at the bottom of zig-zag plane of Al2Y(311). The density of states revealed that the variation of d-orbital electrons of Mg atom became apparent during adsorption process. The values of Mulliken charges were 0.898 e in Al4C3(102), 0.410 e in Zr (001) and 0.245 e in Al2Y(311), respectively. This tendency agrees well with the previous experimental results. It indicates the adsorption energy on the closest-packed planes can be regarded as a prerequisite to select new grain refiners for Mg alloys in future.

Sign in / Sign up

Export Citation Format

Share Document