Optimization of Welding Parameters on Wear Performance of Cladded Layer with TiC Ceramic via a Taguchi Approach

Abstract

Thin composite TiC coatings in a metal matrix are ideal for components subject to heavy abrasive wear. This study examines the wear behavior of a cladded layer on a carbon steel surface, in which wear resistance was enhanced by gas tungsten arc welding (GTAW). The effects of various parameters on cladded layer wear resistance were assessed using Taguchi's parameter design. Microstructure and cladding surface hardness were assessed by optical microscopy, scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) in a cross section of samples coated under optimum processing conditions. The wear behavior of the cladded layer was studied with a block-on-ring tribometer. Excellent metallurgical bonding was formed between the composite coating and substrate. Coatings were uniform, continuous, and virtually defect free, and particles were evenly distributed in the cladded coating. Hardness was increased from HRB 6.6 to 81 in the cladded layer due to the presence of the hard TiC phase. Coatings reinforced with TiC particles revealed higher wear resistance compared to the noncladded substrate. The experimental results revealed that the key factors in wear resistance performance are welding current and welding speed. Advanced analyses by SEM indicated that the mechanisms for strengthening the cladded layer include TiC precipitation and dispersion hardening.