Crystal structure and properties of the Ti0.70Mo0.30C alloy

It is shown in the work that the Ti0.70Mo0.30C alloy can be obtained by the high-temperature synthesis method, which is not inferior to tungsten containing alloys in its mechanical and corrosion-resistant properties. The crystal structure of this alloy has been studied by neutron diffraction. The crystal structure of this alloy is face-centered cubic and is described within the space group Fm3m, in which titanium and molybdenum atoms are substituted and statistically occupy 4 b positions, while carbon atoms statistically occupy octahedral 4 a positions.
The averaged total root-mean-square displacement of atoms in the Ti0.70Mo0.30C alloy was determined from neutron diffraction data by least squares and full-profile analysis of diffraction patterns. It is shown that, in titanium carbide TiC, the replacement of a part of metal atoms (Ti) or nonmetal atoms (C) of one sort with another, which differs from the external valence electron configuration, leads to the appearance of large static distortions in the sublattices of the Ti0.70Mo0.30C ternary alloys. TiC0.30N0.70 and TiC0.30N0.70 compared to TiC alloy. Thus, it has been shown that the replacement of a part of titanium atoms Ti with Mo atoms in titanium carbide TiC due to their different external valence electron configurations leads to the appearance of static distortions in the lattices of the Ti0.70Mo0.30C ternary alloys.
It is shown that the microhardness of the Ti0.70Mo0.30C alloy is 19% higher than the microhardness of the two-component titanium carbide alloy TiC. This can be explained by the fact that the arising static distortions in the sublattices of the three-component Ti0.70Mo0.30C alloys lead to an increase in its microhardness compared to the two-component titanium carbide TiC alloy. The appearance of large static distortions, apparently, leads to deceleration of dislocation motions in the three-component alloy. Consequently, replacing a part of Ti atoms with Mo, as well as apart of C atoms for N in the lattice of titanium carbide TiC, can be a way of changing the dynamic characteristics of its crystal lattice. The results can be used in the field of structural materials science.

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