Oxygen-covered tungsten crystal shape: time effects, equilibrium, surface energy and the edge-rounding temperature

TL;DR

This study investigates how oxygen-covered tungsten crystal shapes change with temperature, revealing an edge-rounding transition between 1300 K and 1430 K and measuring surface energy ratios using ultrafast quenching.

Contribution

It provides new insights into the temperature-dependent equilibrium shapes and surface energies of oxygen-covered tungsten crystals using a novel ultrafast quenching method.

Findings

Edge-rounding transition occurs between 1300 K and 1430 K.

Surface energy ratio γ(111)/γ(211) varies with temperature.

Ultrafast quenching enables high-temperature ECS analysis.

Abstract

The equilibrium crystal shape (ECS) of oxygen-covered tungsten micricrystal is studied as a function of temperature. The specially designed ultrafast crystal quenching setup with the cooling rate of 6000 K/s allows to draw conclusions about ECS at high temperatures. The edge-rounding transition is shown to occur between 1300 K and 1430 K. The ratio of surface free energies $\gamma(111)/\gamma(211)$ is determined as a function of temperature.