Tribological behavior of CrN-coated Cr-Mo-V steels used as die materials

DIN 1.2343 and 1.2367 steels are commonly used as die materials in aluminum extrusion, and single/duplex/multi-coatings enhance their surface properties. The design of an appropriate substrate/coating system is important for improving the tribological performance of these steels under service conditions because the load-carrying capacity of the system can be increased by decreasing the plastic deformation of the substrate. In this study, the tribological behavior of CrN-coated Cr-Mo-V steels (DIN 1.2343, 1.2367, and 1.2999 grades) was investigated using different setups and tribological pairs at room and elevated temperatures. The aim of this study was to reveal the wear resistance of a suggested system (1.2999/CrN) not yet studied and to understand both the wear and the failure characteristics of coated systems. The results showed that (i) among the steels studied, the DIN 1.2999 grade steel exhibited the lowest friction coefficient because it had the highest load-carrying capacity as a result of secondary hardening at elevated temperatures; (ii) at room temperature, both abrasive tracks and adhesive layers were observed on the worn surfaces; and (iii) a combination of chemical reactions and progressive oxidation caused aluminum adhesion on the worn surface, and the detachment of droplets and microcracking were the characteristic damage mechanisms at high temperatures.

Tribological behavior of CrN-coated Cr–Mo–V steels used as die materials

DIN 1.2343 and 1.2367 steels are commonly used as die materials in aluminum extrusion, and single/duplex/multi-coatings en-hance their surface properties. The design of an appropriate substrate/coating system is important for improving the tribological performance of these steels under service conditions because the load-carrying capacity of the system can be increased by decreasing the plastic deforma-tion of the substrate. In this study, the tribological behavior of CrN-coated Cr-Mo-V steels (DIN 1.2343, 1.2367, and 1.2999 grades) was investigated using different setups and tribological pairs at room and elevated temperatures. The aim of this study was to reveal the wear re-sistance of a suggested system (1.2999/CrN) not yet studied and to understand both the wear and the failure characteristics of coated systems. The results showed that (ⅰ) among the steels studied, the DIN 1.2999 grade steel exhibited the lowest friction coefficient because it had the highest load-carrying capacity as a result of secondary hardening at elevated temperatures; (ⅱ) at room temperature, both abrasive tracks and adhesive layers were observed on the worn surfaces; and (ⅲ) a combination of chemical reactions and progressive oxidation caused alumi-num adhesion on the worn surface, and the detachment of droplets and microcracking were the characteristic damage mechanisms at high temperatures.