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Metallic glasses have been applied in industry owing to their attractive mechanical, physical, and chemical properties. such as high electrical resistivity, soft-type superconductivity, good magnetic softness, high strength and large elastic strain. These unusual properties make the amorphous alloys potentially useful for various applications, which originate from the intrinsic random atomic configuration. but their plasticity is low and this disadvantage limites their applicable range as a engineering material. In this study we try to improve plasticity of metallic glasses by structural rejuvenation. Structural rejuvenation in metallic glasses by a thermal process (i.e. through recovery... 

Metallic glasses (MG) are a group of materials that have unique properties such as high yielding strength and high elastic deformation. Because of limitation in the production of these materials, a few industrial materials of MG have been made so far. A few of binary alloys, like binary alloys made of Cu-Zr, have high Glass Forming Ability (GFA) in medium cooling rates. Between two binary systems of Cu-Zr and Ni-Zr, although constituent elements in aspect of atomic radius, electronic structure, physical properties, phase diagrams and intermetallic compounds are so similar to each other, but GFA between them are very different. For example, in Cu-Zr system there are compounds, such as... 

In this work, structures of Cu-Zr bulk metallic glasses at atomic scale were studied by molecular dynamics simulation. Bulk metallic glasses have high glass form ability, which makes it possible to more effectively examine the relationship between structure and properties in glassy materials. Due to this reason, this family of materials has been selected in this research. Voronoi tessellation method, coordination number analysis, short-range order examination, glass transition temperature and pair distribution function have been selected to investigate the structure in atomic scale. Results show that full icosahedron (with the highest five-fold symmetry) and some distorted icosahedra have... 

bulk metallic glass Unlike metal materials that have a crystalline structure, amorphous glass is an amorphous material with an irregular atomic structure that simultaneously has the same physical properties as metals. Due to the absence of crystal defects such as dislocation and grain boundaries, these materials show unique mechanical properties such as high strength and elastic strain, abrasion resistance and proper corrosion. However, their plastic deformation is heterogeneous, concentrated, and accompanied by sudden failure. Unlike metals, these materials do not have a long-range crystalline order, and their atomic structure includes short-range and mid-range order. The short-range order... 

Recent research suggests that the electrochemical deposition of cobalt-based binary alloys, such as cobalt-tungsten and cobalt-iron, can lead to the formation of amorphous structures in the coatings. Theoretical studies suggest that these structures are equivalent to structures created by the melt cooling of the alloy at speeds of about 〖10〗^10 Kelvin per second. The formation of a glass phase can significantly increase the abrasion resistance and corrosion resistance of these coatings. Empirical studies show that the ability of the glass to become glassy, or more precisely, the transition from crystalline to amorphous, is largely a function of the chemical composition. Simulation of... 

In this research, Mg-Zn bulk metallic glasses have been investigated using molecular dynamics simulation. In order to study the structure of this alloy, coordination number, short and medium order of chemical range, Voronoi analysis, glass conversion temperature and atomic pair distribution function have been used. According to the results, the full icosahedral structure with IS connection type in comparison with other structures has an essential role in the stability of the system during cooling and creating medium-scale areas. The results show that the ability to form glass depends on the chemical composition and cooling rate. In this research, the cooling rate is considered to be 1011 K/s... 

Bulk metallic glasses (BMGs), in contrast to conventional crystalline materials, are defined as metals with an amorphous and disordered atomic-scale structure. Due to the absence of dislocations and grain boundaries, BMGs have considerably unique mechanical properties such as high strength and elastic strain, high wear resistance and desirable corrosion resistance. However, they generally suffer from poor plasticity caused by an inhomogeneous deformation which leads to catastrophic failure by localization of strain into narrow regions, known as shear bands. This factor has extremely restricted their application as advanced structural materials. Furthermore, the recently discovered phenomenon...