Complex Nonlinear Deformation of Nanometer Intergranular Glassy Films in -Si3N4

Role of Lu and La in the intergranular films on growth of the prism surface in β-Si3N4: A molecular dynamics study

Atomistic structure of calcium silicate intergranular films between prism and basal planes in silicon nitride: A molecular dynamics study

Molecular dynamics simulations of approximately 15 Å thick intergranular films (IGFs) containing SiO2 and CaO in contact with two surface terminations of the prism (101̄0) and basal planes (0001) of Si3N4 were performed using a multibody interatomic potential. Samples with the same composition (1.5 mol% CaO) and number of atoms but different crystal planes (i.e., the prism and basal planes of Si...

Intergranular films at metal–ceramic interfaces Part I – interface structure and chemistry

In this work the structure and chemistry of intergranular films at metal–ceramic interfaces was investigated via detailed microstructural characterization of model metal–Al2O3 nanocomposites. We report here experimental results indicating the formation and stability of equilibrium nanometer-thick films at metal–ceramic interfaces. Thin 1 nm interface films were observed for two different metal–...

Molecular dynamics simulations of the atomistic structure of the intergranular film between silicon nitride grains: Effect of composition, thickness, and surface vacancies

Molecular dynamics computer simulations were used to study the atomistic structure of intergranular films (IGFs) between two basal oriented Si3N4 crystals or between combined basal and prism oriented crystals. Ordering of the ions into the IGF induced by the crystal surfaces was observed using density profiles of the ions, although that ordering is effected by the roughness of the crystal surfa...

Thin intergranular films and solid-state activated sintering in nickel-doped tungsten

Nickel-doped tungsten specimens were prepared with high purity chemicals and sintered. Although activated sintering starts more than 400 C below the bulk eutectic temperature, the nickel-rich crystalline secondary phase does not wet the tungsten grain boundaries in the solid state. These results contrast with the classical activated sintering model whereby the secondary crystalline phase was pr...