Atomistic Structure of High Index Surfaces

1996 ◽  
Vol 440 ◽  
Author(s):  
Batsirai Mutasa ◽  
Diana Farkas

AbstractInteratomic potentials of the embedded atom (EAM) type were used to study the atomistic structure of high index surfaces in metals and ordered alloys. The results show that a structural unit model can be developed to model the structure of the high index surfaces on the basis of the structure of a few low energy surfaces. The model can predict the structural features and give an estimate of the energies of the higher index surfaces. We present examples of Fe, B2 FeAl and NiAl.

1989 ◽  
Vol 4 (1) ◽  
pp. 62-77 ◽  
Author(s):  
S. P. Chen ◽  
D. J. Srolovitz ◽  
A. F. Voter

We have used “local volume” (embedded atom) type potentials to study the surfaces and grain boundaries of Ni, Al, and Ni3Al. The simulations show that with appropriately fit potentials, the surface and grain boundary structure can be realistically calculated. The surface rippling and relaxation show good agreement with experiments. The energies of most surfaces and grain boundaries also agree with existing data. The structural unit model for grain boundaries in Ni3Al shows the same generic units as in pure metals, but with large variations due to distortions and multiplicity. The utility of the structural unit model is thus more limited for alloys. The grain boundary energies were found to be the highest for Al-rich Ni3Al grain boundaries, and depend significantly on the local composition of the grain boundary. The cusps in the grain boundary energy as a function of misorientation angle are different for different grain boundary stoichiometries. The Ni3Al grain boundaries have approximately the same grain boundary energy and cohesive energy as that of Ni.


1990 ◽  
Vol 193 ◽  
Author(s):  
M. Khantha ◽  
V. Vitek ◽  
M. Goldman

ABSTRACTA systematic geometrical procedure for predicting favored boundaries in the structural unit model is presented. The method is applicable to both symmetric and asymmetric tilt boundaries. The predictions are confirmed by modeling the structures of tilt boundaries belonging to low symmetry ( and [221]) axes in f.c.c. and b.c.c. structures. The results confirm the applicability of the structural unit model for relatively high-index tilt axes.


1992 ◽  
Vol 291 ◽  
Author(s):  
Ademola Taiwo ◽  
Hong Yan ◽  
Gretchen Kalonji

ABSTRACTThe structure and elastic properties of Ni/Cu and Ni/Au multilayer systems are investigated as a function of the number of Ni monolayers built into the systems. We employed lattice statics simulations with the interatomic potentials described by the embedded-atom method. For the Ni/Cu systems, coherent interfaces and FCC structure are maintained, and no elastic anomaly is found. For the Ni/Au systems, when the Ni layers are thick enough, they undergo a strain-induced phase transformation from FCC to HCP structure. An enhancement of Young’s modulus of these systems is found to be associated with this structural change.


Nanoscale ◽  
2021 ◽  
Author(s):  
Xiaocang Han ◽  
Wenqian Chen ◽  
Rui Su ◽  
Yuan Tian ◽  
Pan Liu ◽  
...  

The properties of Zeolitic imidazolate frameworks (ZIFs) crystals highly depend on the structures of the low-energy surfaces, such as {110} of ZIF-8. However, the atomic/molecular configurations of the ZIF-8 {110}...


1988 ◽  
Vol 100 ◽  
Author(s):  
Davy Y. Lo ◽  
Tom A. Tombrello ◽  
Mark H. Shapiro ◽  
Don E. Harrison

ABSTRACTMany-body forces obtained by the Embedded-Atom Method (EAM) [41 are incorporated into the description of low energy collisions and surface ejection processes in molecular dynamics simulations of sputtering from metal targets. Bombardments of small, single crystal Cu targets (400–500 atoms) in three different orientations ({100}, {110}, {111}) by 5 keV Ar+ ions have been simulated. The results are compared to simulations using purely pair-wise additive interactions. Significant differences in the spectra of ejected atoms are found.


2021 ◽  
Vol 248 ◽  
pp. 02058
Author(s):  
Kaitai Hua

Considering the problems such as long duration of defrosting, low working reliability and high energy consumption of refrigerated containers, this paper put forward a new defrosting method combining air and electro-thermal energy, and designed a new defrosting structure system based on the structural features of refrigeration modules of refrigerated containers. The two-variable method of wind pressure change and temperature difference change on both sides of the evaporator was used to detect frosting, and the specific controlling strategy supporting the new defrosting system was provided to realize the effect of intelligent defrosting. It can provide references for fast defrosting, intelligent defrosting and low energy consumption defrosting of refrigerated containers.


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