Development and comparison of HVOF and laser DED methods for depositing TiC-Ni3Al based coatings
Date
2023-08-17
Authors
Russell, Zhila
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Deposition of TiC-Ni3Al composite coatings by high velocity oxyfuel (HVOF) and directed energy laser deposition (DED) was investigated for enhancements, modifications and/or repairs of steel surfaces with extensive wear and oxidation characteristics. Gelation of sodium alginate was employed as an aid to preposition aqueous suspensions, comprised of micron-sized ceramic-metal particles, into micron-sized spherical ‘cermet’ feed-stock powders. Spraying a sodium alginate containing ceramic-metal particle suspension, with a suitable air atomizing nozzle, into an aqueous bath was outlined as a solution to produce nominally spherical ‘cermet’ feedstock for HVOF thermal spraying.
Consequently, dip coating of substrate in colloidal suspension containing ceramic-metal particles, has been suggested as an efficient method for layer-by-layer deposition of preplaced cermet feed stock prior to the laser processing. Processing parameters were identified in the case of both HVOF and DED deposition procedures for optimum structural and mechanical characteristics of fabricated builds.
Description
Cermet coatings were subjected to microstructural and mechanical characterization through combination of latest available techniques and results are provided in relation to several processing parameters. Improved wear resistance, hardness, scratch resistivity and corrosion behavior of the coated substrates suggest the effectiveness of proposed routes.
Keywords
Thermal spray, High velocity oxyfuel, Cermets, Wear, Corrosion, Scratch resistance, Hardness, DED