Hostname: page-component-7bb8b95d7b-w7rtg Total loading time: 0 Render date: 2024-09-13T02:25:25.684Z Has data issue: false hasContentIssue false

Mechanical behaviors of nanocrystallites-amorphous matrix

Published online by Cambridge University Press:  26 February 2011

Michael L. Falk
Affiliation:
Department of Materials Science and Engineering University of Michigan
Get access

Abstract

Format

This is a copy of the slides presented at the meeting but not formally written up for the volume.

Abstract

Bulk metallic glass (BMG) has been of intense interest recently because of its unique combination of excellent mechanical properties including high strength. One of the major drawbacks of monolithic BMG materials is the limited ductility due to strain localization. Except a few recent reports on monolithic ductile BMG, the most popular method to enhance the ductility of the BMG samples is to introduce a crystalline or quasicrystalline phase by precipitation or mixing. The composite material usually exhibits some degree of strain hardening along with significantly higher impact resistance and fracture toughness. However, the mechanism of this strain hardening is not well understood. We present simulated uniaxial compression tests on a monatomic model amorphous system embedded with body-center cubic (BCC) nanocrystals. The advantage of this model system is that intimate amorphous-crystal interfaces can be obtained. We observe that when comparing to monolithic glassy samples where a single shear band normally dominates, multiple shear bands appear in the BCC-amorphous composite samples. The plastic deformation initiates at the interfaces between nanocrystals and the glassy phase due to stress concentration. Furthermore, we demonstrate that shear along the bands results in growth of the nanocrystals.

Type
Slide Presentations
Copyright
Copyright © Materials Research Society 2006

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)