Peculiarities of structure formation of layered metal-oxide system Ti-Ta-(Ti,Ta)xOyduring electro-spark alloying and thermally stimulated modification

Abstract

ABSTRACT The study focuses on high-performance combined electro-spark alloying of titanium and titanium alloy (VT1-0, VT16) surface and porous matrix struct ure oxidation. The metal-oxide coatings morp hology is the result of melt drop transfer, heat treatment, and oxidation. The study establishes the influence of technological regimes of alloying and oxidation on morphological heterogeneity of biocompatible layered metal-oxide system Ti-Ta-(Ti,Ta) x O y . It was found that during electro-spark alloying the concentration of tantalum on the tita nium surface ranges from 0.1 to 3.2 at.%. Morphology of the deposited splats is represented by uniformly grown crystals of titanium and tantalum oxides, which increase from nano- to submicron size. Keywords: high-frequency currents, electro-spark alloying, titania, tantalum pentoxide, tantalum, metal-oxide coating 1. INTRODUCTION Titanium and tantalum are applied in medicine due to their high biocompatibility. Previously, these metals were mainly used for the production of corrosion-resistant construction components operating at high temperatures. Particular attention was paid to the study of the oxidation kinetics, weight gain, chemical and phase transformations occurring in the microstructure