Investigation of thermodynamic stability for copper and nickel amorphous metals by means of molecular dynamics method

In this study, general properties of amorphous substances were made and the importance in technology of this substances were mentioned. Using the EAM method , by means of molecular dynamics simulations , liquid copper and nickel were cooled with cooling rates of 10^12 K/s , 10^13 K/s , 10^14 K/s in order to produce the amorphous copper and nickel. Produced amorphous copper and nickel were kept for 2. 10^(-9) s at 100 K, 200 K, 300 K, 400 K temperatures. The structural stability against time of amorphous copper and nickel for a time period of 2. 10^(-9) s was determined taking into account crystallisation. In addition, while amorphous copper was heated from 100 K to 1390 K with temperature increment of 30 K and amorphous nickel was heated from 100 K to 1820 K with the same temperature increments, thermal stability of the amorphous copper and nickel were determined.According to the findings, it has been determined that at least 1013 K/s or more temperature rates are needed in order to obtain amorphous nickel and copper. Also, it has been found that, as increasing in the temperature rates both the thermal stability of the models and time stability increase. In addition, it has been shown that the stability of amorphous nickel is higher than amorphous copper.