Influence of Heat Treatment on the Microstructure and Wear Properties of Arc-Sprayed FeCrAl/Al Coating

Abstract

Intermetallic compounds formed during heat treatment of alloy coatings affect the coating structure and properties. In order to determine the phase changes and coating performance, FeCrAl (Fe Bal., Cr 26 wt.%, Al 6 wt.%) and Al (99.9 wt.%) coating was sprayed onto low carbon steel substrates and subsequently heat-treated at different temperatures. The effects of heat treatment on the microstructure, phase composition, tensile bonding strength, microhardness, and wear properties of the coatings were analyzed. The as-sprayed coating had a dense, layered structure with an average porosity of 3.6%. The microhardness of the as-sprayed coating was comprised of hard FeCrAl splats and ductile Al splats with an average microhardness value of 494 HV0.1. The coating at 300 °C had the highest tensile strength of 37.5 MPa. At 500 °C, FeAl intermetallic compounds formed at the phase boundaries due to the diffusion of elements. The coating microhardness and wear resistance were affected by the uniform coating structure and the precipitation of FeAl intermetallic compounds. Compared with the annealed coatings, the as-sprayed coating had the lowest wear rate.

Erosion performance of direct-aged Al2O3-reinforced plasma-sprayed composite coatings at high-temperature conditions

“…HT of sprayed coatings can help reduce residual stress and improve coating adhesion strength and ductility. This can contribute towards improved erosion resistance [20,[47][48][49][50][51] as thermally sprayed coatings with higher levels of residual stresses were more sensitive to micro-cracking that might promote higher erosion rates [47,52].…”

Effect of Heat Treatment on the Electrochemical and Tribological Properties of Aluminum-Bronze Coatings Deposited Used the Thermal Spraying Process

“…While heat treatment increased hardness, the precipitation of brittle FeAl intermetallics deteriorated the wear resistance at higher temperatures. The coating annealed at 700 • C exhibited improved wear properties over other annealed coatings due to the formation of Fe 3 Al phases and iron oxide lubricating films [14].…”

Field and Laboratory Wear Tests of Machine Components Used for Renovation of Dirt Roads—A Case Study

“…These coatings can be made of various materials, such as polymers [ 14 ], ceramics [ 15 ] or metal alloys [ 16 ], which provide a harder and more durable surface. Another method of reducing wear is also to modify the surface layer of parts by applying heat treatment [ 17 ]. Heat treatments, such as quenching and tempering, can increase the hardness and strength of a material [ 18 ].…”