Microstructure and wear behaviour of plasma transferred arc (PTA)-deposited FeCrC composite coatings on AISI 5115 steel

Abstract

Plasma transferred arc (PTA) cladding was used to produce composite coatings on the surface of AISI 5115 steel using five different energy inputs and ferrochromium (FeCrC) powder. The effects of different energy inputs and of ferrochromium powder on the microstructure, hardness, and wear behaviour were investigated. The dry-sliding wear properties of the samples were determined using the ball-on-disk wear test method. The alloyed surfaces exhibited increases in hardness and wear resistance and a decrease in the coefficient of friction. The increase in hardness was explained by the presence of hard phases, such as the martensitic phase, Cr7C3, C3Cr7, Fe23C6 and iron carbides, in the microstructure. The average coefficient of friction value of the substrate was determined to be 0.83, whereas these values for the composite layers varied between 0.62 and 0.73. The lowest wear rate (2.88×10−6mm3/N/m) was observed for the 100A PTA cladding sample. The industrial coating process was applied to an AISI 5115 steel rolling cylinder using the optimum parameters (100A), which were determined after experimental studies. The PTA cladding process on the rolling cylinder improved the useful life by approximately 2.5-fold compared to the actual rolling cylinder.