Abstract
Broadly speaking, the research and design of coatings are generally studied by way of single-track deposits; otherwise, the development of a coated part entails the understanding of how multi-track welding influences the microstructure and properties of the surface. This study evaluated the effect of track overlap on the microstructure and properties of the CoCrMoSi Tribaloy T400 alloy coatings produced on AISI 316L steel substrate. The characterization was performed by scanning electron microscopy, hardness and X-ray diffraction. The correlation between the degree of overlap and performance of the coatings was assessed by wear tests. The single track deposits showed hypoeutectic microstructure as a result of high Iron, Chromium and Nickel content. From the second track on, the chemical composition was displaced back to eutectic and then to hypereutectic with overlap of 25 and 50%, respectively. The microstructure dictated the hardness of the coatings (527 – 701 HV0.5) and the lower mass loss rate was measured for hypereutectic with primary Laves phase.
Highlights
Different processes are used to produce coatings and the techniques which promote metallurgical bonding affect the microstructure features of alloys
The first track of CoCrMoSi coating processed with 180 A deposition current exhibited
The expected hypereutectic microstructure comprised of primary Laves phase and eutectic lamellar with Laves phase and Cobalt solid solution observed on cast CoCrMoSi alloy T400 was not identified on the first track of the coatings[9]
Summary
Different processes are used to produce coatings and the techniques which promote metallurgical bonding affect the microstructure features of alloys. The production of welded coatings must consider the interaction between the deposition alloy and the substrate, as higher dilution induces lower hardness of the coatings. This reduction in hardness has been attributed to several factors, including the participation of the chemical elements (such as iron, chromium and nickel) from the steel substrates[10,11,12]. This study evaluated CoCrMoSi alloy coatings in order to establish the correlation between the degree of track overlap on the PTA processing and the coatings features. The influence of overlapping degree on the microstructure, hardness and wear performance of the coatings was assessed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
