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arXiv · 2011.13827

Recrystallization Characteristics of Catalytic Alloy and Graphite in Diamond Synthesis

Sang Jun Cha·Myong Chol Pak·Kwang-Il Kim·Su Gon Kim
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Abstract

We first consider the recrystallization characteristics of catalysis alloy and graphite in the process of diamond synthesis under the condition of super high pressure and high temperature in catalysis method. In the process of diamond synthesis catalysis metal is plastically deformed by increase of pressure and then recrystallized as increasing the temperature. As catalysis metal is recrystallized, the shape of graphite particle is in spherical shape in the region contacting with the catalyst but in any shape in the opposite region. In addition, we calculate the electron charge density distribution and cohesive energies of cementite structure using the first principle method to investigate the reciprocal interaction between transient metal elements and carbon atoms in high-temperature catalyst synthesis. After determination of lattice constant parameters, we obtain the cohesive energy by subtracting the total energy of the crystal from the summation of total energies of atoms composing the crystal and dividing it by the number of atoms. Therefore, the effect of the catalyst on the diamond synthesis is to be analyzed theoretically.

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Sang Jun Cha, Myong Chol Pak, Kwang-Il Kim, Su Gon Kim. 2020-11-27. Recrystallization Characteristics of Catalytic Alloy and Graphite in Diamond Synthesis. https://doi.org/10.3103/s1063457621050026

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