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Indexed by:期刊论文

Date of Publication:2013-08-15

Journal:8th Asian-European International Conference on Plasma Surface Engineering (AEPSE)

Included Journals:SCIE、EI、CPCI-S、Scopus

Volume:228

Issue:SUPPL.1

Page Number:S452-S455

ISSN No.:0257-8972

Key Words:Coaxial laser cladding; Ti alloy; Al2O3-13wt. %TiO2; Microstructure; Electron microprobe

Abstract:Spray-dried sintered Al2O3-13wt. %TiO2 powders were directly coated on Ti-6Al-4 V alloy by coaxial laser cladding. The microstructure, elements distribution and phase analysis of the cladding sample were studied by optical microscopy, EPMA, SEM and XRD methods. The results indicated that the coatings with fine metallurgical bonding to the substrate comprised major stable alpha-Al2O3 and demonstrated three different regions of solidification microstructures. One region, at the bottom of the molten pool, contained mainly Ti enrichment columnar grains and randomly scattered ceramic particles, named Transition Zone. The second region, within the 0.1 mm scope above the transition zone, contained mainly fine equiaxed Al2O3 grains. The third region, at the upper zone of the molten pool, showed coarse equiaxed and cellular Al2O3 grains with obvious segregation of Ti and V elements. The mechanisms of microstructure formation, elements migration and segregation in the experiment were discussed. (C) 2012 Elsevier B.V. All rights reserved.