Abstract
Aluminizing process is an important technology in which aluminum is introduced into the surface of base material. In this work, aluminized layers were produced by the pack cementation process on Inconel 600, Inconel 625 and Nimonic 90 nickel-based alloys. Powder mixture contained 80% of Al and 20% of Fe–Cr. Microstructure, hardness, chemical composition and heat resistance were investigated. The microstructure consisted of intermetallic phases near the surface, and below them, the solid solution was observed. The oxidation resistance at elevated temperature of alloys with the layer was compared with pure alloys. After 20-h annealing at 1000 °C, the phase analysis was carried out. On the Nimonic 90 with aluminized coatings, a lot of Cr2O3 and Al2O3 oxides were produced, whereas on the pure Nimonic 90, a lot of NiO oxides were observed. It was found that the best heat resistance was obtained for the layer produced on the Nimonic 90.
Highlights
Ni-based alloys are modern materials which have a lot of important applications, for example, turbine blades in jet engines or some stuff for the heat treatment furnaces [1]
The oxidation resistance at elevated temperature of alloys with the layer was compared with pure alloys
The Ni alloys which are used in heat treatment furnaces have to be characterized by high oxidation resistance
Summary
Ni-based alloys are modern materials which have a lot of important applications, for example, turbine blades in jet engines or some stuff for the heat treatment furnaces [1]. To improve properties of Ni superalloys, surface technology is often applied, e.g., diffusion aluminizing is very popular The chromoaluminized coating consists of Al2O3 and Cr2O3 phases on the surface This process can be used to modify the materials as follows: steel [1, 14], austenitic steel [15] or Ni-based alloys [16, 17]. The microstructures, chemical and phase compositions, hardness and heat resistance of aluminized coatings modified by chromium on Ni-based alloys were presented (Inconel 600, Inconel 625 and Nimonic 90). We have shown great improvement in the nickel-based alloys properties This investigation has shown that the aluminizing layers can be very interesting in high-temperature applications. Aluminizing process allows protection of the surface of Ni alloys by producing, during oxidation, the continuous and compact layer which consist of the alumina and chromium oxides (Al2O3 and Cr2O3, respectively) on Nimonic 90 alloy
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
