Measurement of chemical and geometrical surface changes in a wear track by a confocal height sensor and confocal Raman spectroscopy

Abstract

Geometrical and chemical changes in the wear track can cause a drift in friction level. In this paper, chemical and geometrical surface changes in wear tracks are analyzed. For this, a setup with a confocal height sensor was developed to measure the local height changes on the wear track, combined with confocal Raman spectroscopy to determine the chemical changes at the surfaces. Pin-on-disc experiments were performed at room temperature and at elevated temperature (600 1C) to understand the material behavior between mild and severe wear regimes. The wear tracks developing between the two ceramics, alumina (Al 2 O 3 ) and zirconia (Y-TZP), were analyzed using these techniques. The results of confocal height sensor showed significantly more geometrical changes in surface roughness at 600 1C compared to the test conducted at room temperature. The developed roughness in the wear track was approximately 250 times larger at 600 1C due to the higher degradation of the mechanical properties of ceramic. Further, material transfer was observed for the test conducted at 600 1C using Raman Spectroscopy. Material transfer at room temperature is difficult to observe because surface changes are less evident in mild wear regimes. The results show that the changes in the micro-geometry of the surface and the chemical compositions of the surface influence the friction level and wear processes. The confocal height sensor and Raman Spectroscopy were used to measure and understand the geometrical and chemical changes occurring on the surface of a wear track during sliding in a single setup.

Dry High Speed Orthogonal Turning of Titanium Alloy Wear Evolution and Chip Morphology

“…Flank wear is caused mainly by abrasion of the hard second phase in a work material. Crater wear is controlled by a combination of adhesion, abrasion, dissolution, and/or diffusion [15,17,25,27,29,30]. At present, it is not clear exactly which mechanisms dominate crater wear in relation to the cutting condition.…”

“…At present, it is not clear exactly which mechanisms dominate crater wear in relation to the cutting condition. In high-speed machining, crater wear is believed to be dominated by dissolution wear and subsequent diffusion [15][16][17][25][26][27]. The aim of this paper is to explain qualitatively the high crater wear resistance of multilayer coated carbides through the observation and analysis of their confocal topography.…”