Precious metal amorphous AgAuSi: Alloy design by swapping gold for silver

Publikationen: Beitrag in FachzeitschriftArtikelForschung(peer-reviewed)

Autoren

  • Lisa-Marie Weniger
  • Christoph Gammer
  • Marek Niewczas
  • Megan J. Cordill
  • Philippe Djemia
  • Damien Faurie
  • Chen-Hui Li
  • Alice Lassnig

Externe Organisationseinheiten

  • McMaster University Canada
  • Sorbonne Université
  • Erich-Schmid-Institut für Materialwissenschaft der Österreichischen Akademie der Wissenschaften

Abstract

To expand the basis for property-oriented material design, complex relationships between chemistry, atomistic structure, and properties of sputter-deposited AgxAu85-xSi15 alloys are investigated using versatile experimental methods. According to differential scanning calorimetry and X-ray diffraction data, the alloys are amorphous within a wide compositional range of 20 ≤ x ≤ 60 at%. However, high-resolution transmission electron microscopy revealed noticeable amounts of crystallites in limiting compositions with x = 20 at% and x = 60 at%. Glass transition and crystallization temperatures grow with increasing Ag content, while room-temperature resistivity and temperature coefficient of resistance are shown to be highly sensitive to the amount of crystalline phase. Neither the existence of nanocrystallites nor the substitution of Ag by Au affected significantly the mechanical properties. All compositions exhibit similar nanoindentation hardness of about 4.3 GPa, Young’s modulus of about 55 GPa, and macroscopic elastic limit of about 2%. The unique combination of high hardness, high elastic strain but low Young’s modulus together with the expected chemical inertness inherited from noble metals makes this alloy family suitable for biomedical applications in form of coatings or in jewelry if an economic bulk production route will be developed.

Details

OriginalspracheEnglisch
Aufsatznummer112099
Seitenumfang11
FachzeitschriftMaterials and Design
Jahrgang232.2023
AusgabenummerAugust
Frühes Online-Datum17 Juni 2023
DOIs
StatusVeröffentlicht - 17 Juni 2023