Atomistic Simulations of Copper Precipitation and Radiation Induced Segregation in α-Iron

2008 ◽  
pp. 107-112
Author(s):  
Frédéric Soisson ◽  
Chu Chun Fu
Keyword(s):  
Atomistic Simulations ◽  
Copper Precipitation ◽  
Radiation Induced

Atomistic Simulations of Copper Precipitation and Radiation Induced Segregation in α-Iron

2008 ◽  
Vol 139 ◽  
pp. 107-112 ◽  
Author(s):  
Frédéric Soisson ◽  
Chu Chun Fu
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Simulations ◽  
Ab Initio Calculations ◽  
Ab Initio ◽  
Point Defects ◽  
Thermal Ageing ◽  
Atomistic Simulations ◽  
Precipitation Kinetics ◽  
Copper Precipitation ◽  
Radiation Induced

We present Monte Carlo simulations of the first stages of the coherent precipitation of Cu in α-Fe during thermal ageing and under irradiation. The simulations are based on a diffusion model by vacancy and self-interstitial jumps, the parameters of which are fitted on ab initio calculations. The simulations of precipitation kinetics during thermal ageing are compared with experimental ones. They reveal that precipitates containing up to several tens of atoms can be much more mobile than individual copper atoms, due to the trapping of vacancies in Cu. Monte Carlo simulations are also used to analyze the coupling between fluxes of point defects and Cu which occurs under irradiation and the possible resulting radiation induced segregation phenomena.

scholarly journals Atomistic Simulations of Phase Transformation of Copper Precipitation and Its Effect on Obstacle Strength in α-iron

2010 ◽  
Vol 59 (8) ◽  
pp. 583-588 ◽  
Author(s):  
Tomohito TSURU ◽  
Yosuke ABE ◽  
Yoshiyuki KAJI ◽  
Takashi TSUKADA ◽  
Shiro JITSUKAWA
Keyword(s):  
Phase Transformation ◽  
Atomistic Simulations ◽  
Copper Precipitation

Defect-Induced Shifts in the Elastic Constants of Silicon

2002 ◽  
Vol 741 ◽  
Author(s):  
Clark L. Allred ◽  
Jeffrey T. Borenstein ◽  
Marc S. Weinberg ◽  
Xianglong Yuan ◽  
Martin Z. Bazant ◽  
...  
Keyword(s):  
Elastic Constants ◽  
Atomistic Simulations ◽  
Device Performance ◽  
Mems Devices ◽  
Materials Properties ◽  
Radiation Induced ◽  
Mems Device ◽  
The Difference ◽  
Induced Defects ◽  
Constant Shift

ABSTRACTAs MEMS devices become ever more sensitive, even slight shifts in materials properties can be detrimental to device performance. Radiation-induced defects can change both the dimensions and mechanical properties of MEMS materials, which will be of concern to designers of MEMS for applications involving radiation exposure, such as those in a reactor environment or in space. We have performed atomistic simulations of the effect that defects and amorphous regions, such as could be produced by radiation damage, have on the elastic constants of silicon. We have then applied the results of the elastic constant shift calculations to a hypothetical MEMS device, and calculated the difference that would be generated by this effect.

Atomistic simulations of radiation-induced defect formation in spinels:MgAl2O4,MgGa2O4, andMgIn2O4

2006 ◽  
Vol 74 (21) ◽  
Author(s):  
D. Bacorisen ◽  
Roger Smith ◽  
B. P. Uberuaga ◽  
K. E. Sickafus ◽  
J. A. Ball ◽  
...  
Keyword(s):  
Defect Formation ◽  
Atomistic Simulations ◽  
Radiation Induced

Atomistic simulations of radiation induced defect formation in the Er2O3 sesquioxide

2008 ◽  
Vol 266 (12-13) ◽  
pp. 2691-2697 ◽  
Author(s):  
L. Kittiratanawasin ◽  
Roger Smith ◽  
B.P. Uberuaga ◽  
K.E. Sickafus ◽  
A.R. Cleave ◽  
...  
Keyword(s):  
Defect Formation ◽  
Atomistic Simulations ◽  
Radiation Induced

Radiation-Induced Precipitation at Thin Foil Surfaces in Ni-Be Alloys

1982 ◽  
Vol 40 ◽  
pp. 598-599
Author(s):  
T. Mukai ◽  
T. E. Mitchell
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Electron Irradiation ◽  
High Vacuum ◽  
Thin Foil ◽  
Homogeneous Precipitation ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Radiation Induced

Radiation-induced homogeneous precipitation in Ni-Be alloys was recently observed by high voltage electron microscopy. A coupling of interstitial flux with solute Be atoms is responsible for the precipitation. The present investigation further shows that precipitation is also induced at thin foil surfaces by electron irradiation under a high vacuum.

Annealing Of Radiation Damage in Tungsten

1970 ◽  
Vol 28 ◽  
pp. 412-413
Author(s):  
Robert C. Rau ◽  
John Moteff
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Radiation Damage ◽  
Thermal Annealing ◽  
Neutron Fluence ◽  
Dislocation Loops ◽  
Defect Clusters ◽  
Polycrystalline Tungsten ◽  
Transmission Electron ◽  
Radiation Induced

Transmission electron microscopy has been used to study the thermal annealing of radiation induced defect clusters in polycrystalline tungsten. Specimens were taken from cylindrical tensile bars which had been irradiated to a fast (E > 1 MeV) neutron fluence of 4.2 × 1019 n/cm2 at 70°C, annealed for one hour at various temperatures in argon, and tensile tested at 240°C in helium. Foils from both the unstressed button heads and the reduced areas near the fracture were examined.Figure 1 shows typical microstructures in button head foils. In the unannealed condition, Fig. 1(a), a dispersion of fine dot clusters was present. Annealing at 435°C, Fig. 1(b), produced an apparent slight decrease in cluster concentration, but annealing at 740°C, Fig. 1(C), resulted in a noticeable densification of the clusters. Finally, annealing at 900°C and 1040°C, Figs. 1(d) and (e), caused a definite decrease in cluster concentration and led to the formation of resolvable dislocation loops.

Radiation-induced surface decomposition

1983 ◽  
Vol 41 ◽  
pp. 368-369
Author(s):  
M. L. Knotek
Keyword(s):  
Ionizing Radiation ◽  
Atomic Structure ◽  
Chemical Bonding ◽  
Neutral Species ◽  
Radiation Induced ◽  
Physical And Chemical ◽  
Surface Decomposition ◽  
The Relationship ◽  
Electron And Photon ◽  
Surface Bond

Modern surface analysis is based largely upon the use of ionizing radiation to probe the electronic and atomic structure of the surfaces physical and chemical makeup. In many of these studies the ionizing radiation used as the primary probe is found to induce changes in the structure and makeup of the surface, especially when electrons are employed. A number of techniques employ the phenomenon of radiation induced desorption as a means of probing the nature of the surface bond. These include Electron- and Photon-Stimulated Desorption (ESD and PSD) which measure desorbed ionic and neutral species as they leave the surface after the surface has been excited by some incident ionizing particle. There has recently been a great deal of activity in determining the relationship between the nature of chemical bonding and its susceptibility to radiation damage.

Electrochemical nucleation and growth of copper on iron and aluminum: A TEM study of industrial copper cementation

1978 ◽  
Vol 36 (1) ◽  
pp. 454-455
Author(s):  
L.E. Murr ◽  
V. Annamalai
Keyword(s):  
Metal Surface ◽  
Copper Deposit ◽  
Nucleation And Growth ◽  
16Th Century ◽  
Electrochemical Reactions ◽  
Mine Shaft ◽  
De Re ◽  
Copper Precipitation ◽  
Electrochemical Nucleation ◽  
Interesting System

Georgius Agricola in 1556 in his classical book, “De Re Metallica”, mentioned a strange water drawn from a mine shaft near Schmölnitz in Hungary that eroded iron and turned it into copper. This precipitation (or cementation) of copper on iron was employed as a commercial technique for producing copper at the Rio Tinto Mines in Spain in the 16th Century, and it continues today to account for as much as 15 percent of the copper produced by several U.S. copper companies.In addition to the Cu/Fe system, many other similar heterogeneous, electrochemical reactions can occur where ions from solution are reduced to metal on a more electropositive metal surface. In the case of copper precipitation from solution, aluminum is also an interesting system because of economic, environmental (ecological) and energy considerations. In studies of copper cementation on aluminum as an alternative to the historical Cu/Fe system, it was noticed that the two systems (Cu/Fe and Cu/Al) were kinetically very different, and that this difference was due in large part to differences in the structure of the residual, cement-copper deposit.

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