Effect of flame spray deposition parameters on the microstructure, microhardness and corrosion resistance of FeNbC coatings on AISI 1020 steel

Abstract

The present study aimed to produce and characterize FeNbC coatings deposited on AISI 1020 steel using flame spray process (FS) evaluating the influence of powder granulometry, standoff distance, powder feed rate and substrate preheating. FS process parameters variations produce coatings with different properties. Taguchi experimental design based in the L9 orthogonal array and ANOVA statistical analysis were performed. Coating morphology was evaluated using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), the present phases were identified by x-ray diffraction (XRD). Coatings microhardness was evaluated using Knoop hardness test. The coatings corrosion resistance was measured through monitoring the open circuit potential and potenciodynamic polarization in 3.5% NaCl solution. The results indicate that coatings with microhardness average of 1084 HK 0.3 and dispersion of the measured values were associated with heterogeneity and interlamellar oxides formed in the microstructure. All control factors investigated showed significant influence on microhardness. Substrate preheating was the most important factor, followed by the powder granulometry; powder feed rate and standoff distance. The FeNbC coating presented a reduction in the substrate corrosion rate, but the presence of defects in the microstructure, such as porosities, voids and cracks compromised the barrier effects of these coatings.

Brazilian Tribology: origin, status quo and future perspectives

“…The group develops studies considering improving materials' tribological behaviour through surface changes, increasing materials' tribological performance, especially in parts produced by powder metallurgy [333,[358][359][360][361][362][363][364]. The group has been developing niobium-based tool materials (cermets) [365][366][367][368] and zinc-aluminium alloys [369]. Recently, the group started to work on special titanium alloys for biological use.…”

Recent Progress of Metal–Air Batteries—A Mini Review

“…The principle of inkjet printing consists of five stages: drop ejection, drop flight, drop impact, drop spreading, and drop solidification. Inkjet printing has been used in depositing functional inks onto various substrates for numerical devices, to specific, sensors, micro-batteries, solar cell, and other conductive parts of cells [79][80][81][82]. Lim [83] thoroughly reviewed technology issues and influence on different substrates for printed capacitive sensors.…”

Influence of Milling and Use of Ni and Al Containing Metal Binder in NbC-Based Cermets

“…Cermets are composite materials that can combine several properties of interest for applications in machining, such as high wear resistance, toughness 1 and good refractoriness. With certain compositions, cermets can reach hardness values close to hard metals and can also be applied in components or coatings which require, in addition to wear resistance, corrosion resistance 2,3 .…”