Surface gradients in cemented carbides from first-principles-based multiscale modeling : Atomic diffusion in liquid Co

• The kinetic modeling of cemented carbides, where Co is used as binder element, requires a detailed diffusion description. Up to now, no experimental self- or impurity diffusion data for the liquid Co system have been available. Here we use the fundamental approach based on ab initio molecular dynamics simulations to assess diffusion coefficients for the liquid Co system, including six solute elements. Our calculated Co self-diffusion coefficients show good agreement with the estimates that have been obtained using scaling laws from the available literature data. To validate the modeling method, we performed one set of calculations for liquid Ni self-diffusion, where experimental data are available, showing good agreement between theory and experiments. The computed diffusion data were used in subsequent DICTRA simulations to model the gradient formation in cemented carbide systems. The results based on the new diffusion data allows for correct predictions of the gradient thickness.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Materialteknik -- Metallurgi och metalliska material (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Materials Engineering -- Metallurgy and Metallic Materials (hsv//eng)

Nyckelord

Ab initio molecular dynamics

Cemented carbides

DICTRA

Diffusion

ICME

Liquid co

Calculations

Carbide tools

Carbides

Diffusion in liquids

Diffusion in solids

Liquids

Molecular dynamics

Materialvetenskap

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)