Chromium-based oxidation-resistant coatings for the protection of engine valves in automotive vehicles

Abstract

The influence of a thin chromium layer (1 μm) sputter-deposited on the surfaces of four valve steels (X33CrNiMn23-8, X50CrMnNiNbN21-9, X53CrMnNiN20-8 and X55CrMnNiN20-8) was studied at 900°C under isothermal and thermal-shock conditions. It was determined that the oxidation resistance of coated steels is much better than that of uncoated ones. This situation is a result of the formation of highly protective Cr2O3 scales on the surfaces of coated materials. It was also demonstrated that a positive effect of a chromium addition on the oxidation resistance of the investigated steels is observed during a much longer period than the lifetime of a chromium coating.

High-temperature oxidation resistance of chromium-based coatings deposited by DLI-MOCVD for enhanced protection of the inner surface of long tubes

“…These hard coatings could also be of use in high temperature corrosive environments such as those encountered in aeronautics, automotive [26] and some other industries [27] to protect components with 3D complex geometries.…”

Effect of Annealing and Oxidation on the Microstructure Evolution of Hot-Dipped Aluminide Q345 Steel with Silicon Addition

“…In order to reduce room-temperature gas emissions and oil consumption, the use of bioethanol in the automotive industry is gradually increasing; bioethanol and the concentration of ethanol used as a bioadditive in gasoline has increased to about 20% in EU countries [1,2]. It is well-known that after burning bioethanol in engines, the flue gas consists of large amounts of H 2 O and CO 2 , which can significantly increase the reaction rate of steel in motorcycle-and automotive-exhaust-system components, resulting in the components of the exhaust system being subjected to massive oxidation and severe corrosion of steel and its alloys [3][4][5][6]. Low-alloy high-strength steels (Q345) are increasingly used in the automotive industry because of their high strength, good welding properties, and better corrosion resistance, which can save metal materials and reduce the weight of equipment.…”

Nitrogen-Enriched Cr1−xAlxN Multilayer-Like Coatings Manufactured by Dynamic Glancing Angle Direct Current Magnetron Sputtering

“…TM nitride coatings have been improved even further by adding a ternary component to the system, as is the case for (Ti, Al)N and (Cr, Al)N [16]. Cr-based coatings are known to act as an important corrosion and oxidation barriers for metal substrates due to formation of Cr 2 O 3 and other Cr-based phases that can passivate the surface, as described in the literature [17][18][19]. The production of ternary CrAlN has been reported to increase even more anticorrosive and oxidation protection, along with hardness and wear resistance [20,21].…”