[T15] Hard Materials

[17F-T15-11] Effect of Matrix Composition and Welding Parameters on in situ Synthesis of TiC during PTA Cladding

*S. Yöyler¹, A. Surženkov¹, M. Viljus¹, R. Traksmaa¹, K. Juhani¹ (1.Tallinn University of Technology, Estonia)

Keywords:In-situ synthesis, carbide, Fe-based hardfacings, plasma transferred arc welding

The goal of this study is to examine the effects of matrix composition and welding parameters on the in-situ synthesis of TiC from TiO₂ and graphite in plasma transferred arc (PTA) cladded hardfacings. 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), while phase analysis was performed using X-ray diffraction (XRD). Vickers hardness was measured on the surface of the hardfacings. The distribution and synthesis of carbide phases were found to be affected by the welding current.