Nanoscratch-induced deformation behaviour in B₄C particle reinforced ultrafine grained Al alloy composites: a novel diagnostic approach

Abstract

We report on the novel application of nanoscratch characterization to provide insight into the plasticity mechanisms responsible for the behaviour of composites. Accordingly, we conduct deformation characterization with nanoscratch testing (DCNT) to study the deformation behaviour of two B₄C reinforced ultrafine grained Al alloy tri-modal composites with average B₄C particle sizes of ~1–6 μm and ~500 nm, respectively. To highlight the type of mechanistic information revealed in a DCNT study of composites, we concentrate on the influence of B₄C particle size on deformation mechanisms.

Keywords:

• deformation characterization with nanoscratch testing (DCNT)
• metal–matrix composites (MMCs)
• deformation structure

Acknowledgements

The authors acknowledge financial support provided by the Office of Naval Research (ONR) [N00014-12-1-0237] with Dr. Lawrence Kabacoff as the program officer. The authors are also grateful to DWA Aluminium Composites for providing B₄C in Sample II. The TEM and SEM work on the microstructure of Sample I from Dr Ying Li and Dr Zhihui Zhang, respectively, is also highly appreciated.