[T15] Hard Materials

[17F-T15-11] Effect of Feedstock Nature and Cladding Parameters on In-Situ Synthesis of TiC during PTA Cladding

*S. Yöyler¹, A. Surženkov¹, M. Viljus¹, K. Juhani¹ (1.Tallinn University of Technology, Estonia)

Keywords:in-situ synthesis, carbide, feedstock nature, Fe-based hardfacing, PTA cladding

The goal of this study is to examine the effects of feedstock nature and cladding parameters on the in-situ synthesis of TiC from TiO2 and graphite in plasma transferred arc (PTA) cladded hardfacings. The study utilized a feedstock composed of elemental powders (TiO2, graphite, Fe, Cr, Ni, and Mo) instead of pre-alloyed stainless-steel powder. This approach allows for precise control over the composition and promotes the in-situ synthesis of TiC, enhancing the microstructural properties and hardness of the coatings, and enabling future adjustments in the component ratios. The constituent proportions in the feedstock powder (36 wt% TiO2, 23.6 wt% graphite, 26.9 wt% Fe, 7.1 wt% Cr, 5.3 wt% Ni, and 1.1 wt% Mo) remained constant. Before hardfacing deposition, feedstock constituents were subjected to conventional ball milling during 72 hours. Hardfacings were deposited at torch velocity of 0.7 mm/s and currents of 95, 105, 110, 115, and 125 A, respectively. Microstructure analysis was conducted through energy-dispersive spectroscopy (EDS) and scanning electron microscopy (SEM). Vickers hardness was measured on the surface of the hardfacings. The distribution and synthesis of carbide phases were found to be affected by the cladding current.