Interfacial structure and mechanical properties of a new Nb/Re laminated composite
Abstract
The interface structure of a new Nb/Re laminated composite is designed by density functional theory (DFT), and its mechanical properties are verified by experiments. The results show that the new Nb7Re8 composite has excellent hardness (21.3 GPa) and toughness ( {B}_{H}/{G}_{H}=1.8 B H / G H = 1.8 ), which are calculated using a thermodynamic phase diagram and first principles. In addition, the new composite consists of a Nb layer, a transition layer (Nb7Re8 and NbRe3 phase) and a Re layer, which are smooth, uniform and dense. In particular, the transition layer consists of the Nb7Re8 phase and has a zigzag structure, which effectively improves the interfacial bonding properties of the composite. The density of the composite is 12.23 g cm-3, which is only 58.2% of the Re density ( {sigma }_{mathrm{Re}}=21.04 σ Re = 21.04 g cm-3), and the tensile strength is 636 MPa. This new Nb/Re laminated composite can be widely used as a high temperature resistant structural material for aerospace engine nozzles.
- Publication:
-
Materials Research Express
- Pub Date:
- October 2019
- DOI:
- 10.1088/2053-1591/ab231f
- Bibcode:
- 2019MRE.....6j65b1L
- Keywords:
-
- chemical vapor deposition;
- Nb/Re laminated composites;
- phase stability;
- mechanical properties