NOMATEN examines metal glass and alloys with high entropy

Date: 
23.06.2021

The NOMATEN group of scien­ti­sts is looking for con­fi­gu­ra­tio­nal entropy and glass trans­i­tion rela­tion­ships in high-entropy alloys (HEA) using dyna­mic simu­la­tions at the mole­cu­lar level. Dr. Rene Alva­rez-Donado pre­sen­ted some of his team’s results in Janu­ary at the web con­fe­rence „Recent advan­ces on the glass pro­blem” orga­ni­zed by the Cen­ter Euro­péen de Cal­cul Ato­mi­que et Molécu­la­ire (CECAM).

Metallic glass elements (Credits: Björn Gojdka, CC BY 3.0, via Wikimedia Commons)

Con­fi­gu­ra­tio­nal entropy tells us the num­ber of ava­ila­ble atom con­fi­gu­ra­tions in the alloy struc­ture, but we’re still tal­king about non-cry­stal­line mate­rial” – expla­ins Dr. Rene Alva­rez Donado of the NOMATEN Cen­ter of excel­lence at the NCBJ. „The rese­arch results show that the con­fi­gu­ra­tion entropy is a key indi­ca­tor for iden­ti­fy­ing when a mate­rial with a metal­lic glass struc­ture is for­med from high entropy alloys. Glas­ses are solids with an amor­phous struc­ture and the arran­ge­ment of their atoms is not orde­red – unlike cry­stals, which have an orde­red struc­ture – in the case of large entropy coef­fi­cients, con­si­sting of many dif­fe­rent ele­ments, an addi­tio­nal source of entropy is the ran­dom distri­bu­tion of dif­fe­rent atoms.”

In his rese­arch, Dr. Rene Alva­rez – Donado deals with the so-cal­led metal­lic glas­ses (bulk metal­lic glas­ses – BGM). Thanks to the com­bi­na­tion of the advan­ta­ges of metals and glass, this mate­rial is easy to shape, dura­ble and also con­ducts heat and elec­tri­city well. High entropy alloys (HEA) are one of the key rese­arch sub­jects of the NOMATEN Cen­ter of Excel­lence. In the form of solids – HEAs are mate­rials with an orde­red struc­ture and pro­mi­sing pro­per­ties. They are the sub­ject of the­ore­ti­cal and expe­ri­men­tal rese­arch by rese­arch teams respon­si­ble for simu­la­tions and machine lear­ning – the Com­ple­xity in Func­tio­nal Mate­rials group (Prof. Mikko Alava) and Mate­rials Infor­ma­tics – Struc­ture and Func­tion group (Dr. Ste­fa­nos Papa­ni­ko­laou), as well as Func­tio­nal Pro­per­ties group (Prof. Lukas Kur­pa­ska).

Dr. Alva­rez-Donado pre­sen­ted the results of his team’s rese­arch in a pre­sen­ta­tion enti­tled „Con­fi­gu­ra­tio­nal entropy in High Entropy Alloys” at the online con­fe­rence „Recent advan­ces on the glass pro­blem” orga­ni­zed by the Cen­ter Euro­péen de Cal­cul Ato­mi­que et Molécu­la­ire (CECAM). The co-authors of the work are also Prof. Mikko Alava (direc­tor of NOMATEN) and Dr. Amin Esfan­diar­pour and Dr. Ste­fa­nos Papa­ni­ko­laou. The con­fe­rence was an intro­duc­tion to the regu­lar scien­ti­fic con­fe­rence of the same title post­po­ned to Janu­ary 2022.

Metallic glass elements (Credits: Björn Gojdka, CC BY 3.0, via Wikimedia Commons)