1. Al grain boundary segregations in doped intermetallic NiAl and their effect on brittleness at room temperature
- Author
-
Dmitry Wainstein, A. Yu. Rashkovskiy, and A.I. Kovalev
- Subjects
Auger electron spectroscopy ,Nial ,Materials science ,Condensed matter physics ,Fermi level ,Doping ,Intermetallic ,General Physics and Astronomy ,02 engineering and technology ,Intergranular corrosion ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,symbols.namesake ,X-ray photoelectron spectroscopy ,symbols ,Grain boundary ,0210 nano-technology ,computer ,computer.programming_language - Abstract
The nature of intermetallic NiAl brittleness is investigated by Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS) and electron energy-loss fine structure (EELFS) means. It is found that the reason for this phenomenon is the ordering of intermetallic NiAl, accompanied by the formation of aluminum structural segregations at grain boundaries. Doping with 0.1 wt % La transforms the atomic and electronic structures of grain boundaries, eliminating NiAl intergranular fracturing at room temperature. Doping is accompanied by Fermi level shifts and an increase in conduction electron density neff. These factors are responsible for the lower covalence of interatomic bonds in pure intermetallic NiAl. The effect A1 segregations have on the critical deformation of the generating grain boundary fracture in NiAl is discussed.
- Published
- 2016