skip to main content

SciTech ConnectSciTech Connect

Title: Isothermal oxidation behavior and microstructure of plasma surface Ta coating on γ-TiAl

The oxidation behavior of γ-TiAl with Ta surface coating fabricated by double glow plasma surface alloying technology was investigated by thermogravimetric method. Oxidation experiments were carried out at 750 °C and 850 °C in air for 100 h. The modification layer was comprised of deposition layer and diffusion layer, which metallurgically adhered to the substrate. Tantalum element decreased with the case depth. The oxidation morphology was studied by a scanning electron microscope and X-ray diffraction. The results highlighted that in the oxidizing process of the oxidation, the phase containing Ta-richer may restrain diffusing outward of the element Al in the matrix. Ti diffused outward, and formed the TiO{sub 2} scales, while the middle layer was rich in Al, and formed the continuous Al{sub 2}O{sub 3} scales after oxidation, which was effective to prevent further infiltration of oxygen atoms, and as a result the oxidation resistance increased immensely. - Highlights: • A Ta modified coating was prepared on γ-TiAl using DGP surface alloying technology. • The modification layer metallurgically adhered to the substrate. • The bonding force is about 60 N, satisfying the demands of practical use. • The oxidation resistance increased immensely at 750 °C and 850 °C.
Authors:
; ; ; ;
Publication Date:
OSTI Identifier:
22403601
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 98; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALUMINIUM; ALUMINIUM OXIDES; DEMAND; INTERMETALLIC COMPOUNDS; LAYERS; MATRIX MATERIALS; MICROSTRUCTURE; MORPHOLOGY; OXIDATION; PLASMA; SCANNING ELECTRON MICROSCOPY; SUBSTRATES; SURFACE COATING; SURFACES; TANTALUM; THERMAL GRAVIMETRIC ANALYSIS; TITANIUM; TITANIUM OXIDES; X-RAY DIFFRACTION