Study On The Construction Of Ni-Al Alloy Interatomic Potentials

Aluminum alloy is a widely used alloy material, especially in shipbuildingindustry and aviation. Known as a high-temperature structural material with brightfuture, nickel-aluminum alloy has increasingly aroused material researchers’attention with its superior quality of specific tenacity, specific modulus, erosionresistance and inoxidability. Meanwhile, this kind of alloy certainly has somedeficiencies, which lay a hindrance during the application in some aspects. In thelong-term implementation, the researchers found that the quality of alloy has a closerelationship with its microscopic structure, thus, this relationship becomeresearchers’ hot spot.In order to research the relations between alloy’s quality and microscopicstructure thoroughly, a model describing the mutual affection between atom andpotential function must be built, as the imitation carried by computer is recognizedmore and more reliable.This paper present the general information of aluminum alloy and currentresearching situation of nickel-aluminum alloy. In addition, the paper states somecommon material designing theory and the kinds of mutual affection between metalatoms and their application situation, followed by the discussion of their ownadvantages and disadvantages and application field. Focusing on the mutualaffection between atoms, this paper stresses on the description of Embedded AtomMethod, then sets up this paper’s study object: pure Ni, pure Al, NiAl in B2andNi₃Al in fcc structure. Finally, this paper carries out the relative potential functioncalculation, depending on the respective experiment figure.Aiming at testing the credibility and feasibility of the built potential, this paperfinally proving the potential made in this paper is relatively practicable basing on theRose curve. Cutoff and stiffen are chosen to modify and optimize the potential. Afterthe implementation of the two ways, the paper goes to the solutions of the bindingenergy Ec, as well as the further research of the stability of NiAl in B2and Ni₃Al infcc structure. And the conclusion is NiAl in bcc structure is more stable than in fcc and hcp; Ni₃Al in fcc structure is more stable than bcc and hcp. The conclusion is inline with the practice. Otherwise, the paper also explores the P-V relations betweenNiAl in B2and Ni₃Al in fcc. In the end, this paper also studies the single vacancyformation energy of the paper’s researching object and compares the conclusionwith other researchers’. The final conclusion is that the results are correspondingwith the experiments’ figure except for the figure of Al.