Activation volume and energy of bulk metallic glasses determined by nanoindentation. (5th October 2018)

• Record Type: Journal Article
• Authors: Krämer, Lisa; Maier-Kiener, Verena; Champion, Yannick; Sarac, Baran; Pippan, Reinhard
• Is Part Of: Materials & design. Volume 155(2018)
• Page Start: 116
• Page End: 124
• Publication Date: 2018-10-05
• Subjects: Bulk metallic glasses -- Activation volume -- Activation energy -- Nanoindentation strain rate jump tests -- High pressure torsion -- Thermal cycling; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2018.05.051
• Languages: English
• ISSNs: 0264-1275

Abstract

Abstract: Nanoindentation strain-rate jump testing was used to determine activation volumes and energies of various metallic glasses and composites. Three different single phase metallic glasses and three composites (two with amorphous/crystalline Cu and one with an amorphous/amorphous structure) were investigated. The state of the materials was additionally changed by varying the testing temperature between room temperature and 430 °C, by performing high pressure torsion and by thermal cycling. The results show that testing temperature is the main parameter controlling activation volume and energy, whereas material modifications by high pressure torsion and thermal cycling do not significantly affect them. Graphical abstract: Unlabelled Image Highlights: Nanoindentation strain rate jump tests of 3 BMGs and 3 BMGCs Development of new method to determine activation energy and volume of shear transformation zones Testing temperature strongly influences activation energy and volume Rejuvenation (by HPT and thermal cycling) does not influence activation energy and volume