Ver publicación 

Mostrar el registro sencillo de la publicación

Temperature effects on the strength of a nanocrystalline refractory high entropy alloy

dc.contributor.authorRoco, Fiorella R.
dc.contributor.authorDeluigi, O. R.
dc.contributor.authorOpazo, Mario
dc.contributor.authorAmigo, N.
dc.contributor.authorRojas-Nunez, J.
dc.contributor.authorValencia, F.J.
dc.contributor.authorTramontina, D.R.
dc.contributor.authorBringa, Eduardo M.
dc.date.accessioned2025-04-23T19:32:45Z
dc.date.available2025-04-23T19:32:45Z
dc.date.issued2025
dc.identifier.urihttp://repositorio.ucm.cl/handle/ucm/5975
dc.description.abstractRefractory High Entropy Alloys (RHEAs) are advanced materials suitable for high-temperature applications due to their remarkable properties, such as excellent strength, ductility, wear resistance, among others. In this study, the effect of temperature on the mechanical properties of the nanocrystalline bcc HfNbTaZr RHEA is explored under uniaxial loading using molecular dynamics simulations. Temperatures and grain sizes in the range of 100–1200 K and 5–17 nm are considered here. Our results showed that the highest yield strengths and flow stress were achieved in the 10–15 nm range for grain sizes, where the transition from Hall-Petch (HP) to the inverse Hall-Petch (iHP) effect was clearly observed at low temperatures, with a weaker grain size dependence in the HP regime at high temperatures. The MD results align extremely well with a scaling model for the elastic modulus as a function of temperature, and with a strength model which have been extensively employed to understand experimental results up to high temperatures, but the reference strain-rate has to be adjusted to take into account the large values for atomistic simulations. These models are typically based on relatively simple scenarios, like the motion of single straight dislocations, either edge or screw, and lack of dislocation junctions and twinning. Here, deformation includes both edge and screw dislocations, dislocation junctions, grain boundary plasticity, twinning, etc., but the general trend of smooth softening with temperature is observed despite the complex scenario. Some models assume that plasticity in RHEAs would be controlled by edge dislocations but, under the simulated conditions, there are contributions from both edge and screw dislocations. In addition, we quantify twin volume-fraction and find a transition from twin-dominated deformation to dislocation-dominated deformation as temperature increases, with twinning increasing for larger grains. Our results provide quantification of the mechanical properties and plasticity of a nanocrystalline bcc RHEA up to high temperatures, and the proposed adaptation of a strength model allows connection between typical experiments and high strain rate simulations.es_CL
dc.language.isoenes_CL
dc.rightsAtribución-NoComercial-SinDerivadas 3.0 Chile*
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/3.0/cl/*
dc.sourceInternational Journal of Refractory Metals and Hard Materials, 128, 107038es_CL
dc.subjectHigh entropy alloyses_CL
dc.subjectMaterials refractory high entropy alloyses_CL
dc.subjectPlasticityes_CL
dc.titleTemperature effects on the strength of a nanocrystalline refractory high entropy alloyes_CL
dc.typeArticlees_CL
dc.ucm.facultadFacultad de Ciencias de la Ingenieríaes_CL
dc.ucm.indexacionScopuses_CL
dc.ucm.indexacionIsies_CL
dc.ucm.urisciencedirect.ucm.elogim.com/science/article/pii/S0263436825000034?via%3Dihubes_CL
dc.ucm.doidoi.org/10.1016/j.ijrmhm.2025.107038es_CL


Ficheros en la publicación

FicherosTamañoFormatoVer

No hay ficheros asociados a esta publicación.

Esta publicación aparece en la(s) siguiente(s) colección(ones)

Mostrar el registro sencillo de la publicación

Atribución-NoComercial-SinDerivadas 3.0 Chile
Excepto si se señala otra cosa, la licencia de la publicación se describe como Atribución-NoComercial-SinDerivadas 3.0 Chile