Liquid-to-glass transition in bulk glass-forming Cu60Ti20Zr20 alloy by molecular dynamics simulations.

نویسندگان

  • X J Han
  • H Teichler
چکیده

We report results from molecular dynamics studies concerning the microscopic structure and dynamics of the ternary, bulk metallic glass-forming Cu60Ti20Zr20 alloy. In detail we consider the partial radial distribution functions, nearest-neighbor numbers, specific heat, simulated glass temperature, diffusion coefficients, and incoherent intermediate scattering function (ISF). The applied atomic model reproduces well experimental x-ray data of the total radial distribution function. It provides for Cu60Ti20Zr20 a structure with marked intermediate-range order. The ISF is analyzed within an extension of mode-coupling theory, where the effective memory kernel is evaluated from the Laplace transform of the ISF. The dynamics of the system fulfills in most respects the predictions of mode-coupling theory (MCT), up to an absence of the algebraic t{-a} decay in the early beta range. Comparison with the calculated memory kernel shows that this absence can be traced back to deviations of the kernel from its approximate form analyzed in MCT. As by-product, our investigation provides a method to reconstruct around the critical temperature major parts of the memory kernel from lambda and the plateau value f{c} of the ISF, and it indicates why the critical dynamics predicted by mode-coupling theory can be observed in a temperature interval of more than 500 K.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

The viscosity of the Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glass forming alloy in the supercooled liquid

The viscosity of the Zr46.75Ti8.25Cu7.5Ni10Be27.5 bulk metallic glass forming alloy in the supercooled liquid was measured using parallel plate rheometry. The measurements were carried out with different heating rates between 0.0167 and 1.167 K/s as well as isothermally. Because of the high thermal stability above the glass transition of this bulk metallic glass former with respect to crystalli...

متن کامل

Investigating the atomic level influencing factors of glass forming ability in NiAl and CuZr metallic glasses.

Bulk metallic glasses are a relatively new class of amorphous metal alloy which possess unique mechanical and magnetic properties. The specific concentrations and combinations of alloy elements needed to prevent crystallization during melt quenching remains poorly understood. A correlation between atomic properties that can explain some of the previously identified glass forming ability (GFA) a...

متن کامل

Diffusive Dynamicsof Binary Lennard-Jones Liquid in the Presence of Gold Nanoparticle: A Mode Coupling Theory Analysis

Molecular dynamics simulation has been performed to analyze the effect of the presence of gold nanoparticle on dynamics of Kob-Anderson binary Lennard-Jones (BLJ) mixture upon supercooling within the framework of the mode coupling theory of the dynamic glass transition. The presence of gold nanoparticle has a direct effect on the liquid structure and causes the peaks of the radial distribution ...

متن کامل

Molecular dynamic simulation of glass formation in binary liquid metal: Cu–Ag using EAM

Based on the embedded-atom method, a constant-pressure, constant-temperature molecular dynamics technique is applied to obtain an atomic description of glass formation process in eutectic Cu40Ag60 alloy. By using radial distribution function and pair analysis methods, the structure and glass forming ability of this alloy is studied by quenching from the liquid at different cooling rates (1 £ 10...

متن کامل

Thermodynamics and kinetics of the undercooled liquid and the glass transition of the Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 alloy

Differential scanning calorimetry (DSC) was used to determine the thermodynamic functions of the undercooled liquid and the amorphous phase with respect to the crystalline state of the ~41.2Ti13.8CU125Nilo.OBe22.5 bulk mltallic glass forming alloy. The specific heat capacities of this alloy. in the undercooled liquid, the amorphous state and the crystal were determined. The differences in entha...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Physical review. E, Statistical, nonlinear, and soft matter physics

دوره 75 6 Pt 1  شماره 

صفحات  -

تاریخ انتشار 2007