Boriding of steel surface with beams of boron atoms

Abstract

We consider a new method for hardening the steel surface, which differs from the known CHT boriding method in the possibility of creating a surface with a lower fragility. Within this approach, the boriding is carried out by treating the steel surface with atomic beams of boron at a temperature below 750 °C. In this case, a friable layer of pure boron appears on the outer surface of the steel. Then, boron atoms diffuse from this layer into the surface layers of the steel. To detect boron in a steel sample, we used the X-ray photoelectron spectroscopy method. With its help we have obtained spectra of both the outer surface of a steel sample and surface layers at depths up to 8 nm. The spectra of the surface layers showed that as a result of boriding in the sample there appeared the boron in the zero oxidation state. This fact is consistent with the notion that, in the case of a small concentration of boron, it is located on the boundaries between the grains in the surface layer of steel and strengthens the bonds between the boundaries.