AVS 65th International Symposium & Exhibition
    Tribology Focus Topic Tuesday Sessions
       Session TR-TuP

Paper TR-TuP2
Sliding Wear Behavior of Tool Steel Functionalized with Organic Monolayers Against Aluminum

Tuesday, October 23, 2018, 6:30 pm, Room Hall B

Session: Tribology Focus Topic Poster Session
Presenter: Stephan Prünte, RWTH Aachen University, Germany
Authors: S. Prünte, RWTH Aachen University, Germany
D. Music, RWTH Aachen University, Germany
V.L. Terziyska, Montanuniversität Leoben, Austria
C. Mitterer, Montanuniversität Leoben, Austria
J.M. Schneider, RWTH Aachen University, Germany
Correspondent: Click to Email
Tool steel surfaces were functionalized with methyl-terminated monolayers of phosphonic acids firmly attached by an intermediate metal-oxide adhesion layer. Their sliding behavior against aluminum was investigated with a ball-on-disc tribometer. Our results show a 3-fold reduction of friction and wear for a densely functionalized tool steel with an intermediate Cu‑O adhesion layer compared to a non-functionalized sample due to small interactions between Al and the distal methyl moieties of the monolayer. However, functionalized Fe-O adhesion layers on tool steel failed to improve the sliding behavior against Al. This distinct difference may be rationalized by density functional theory calculations. The molecular monolayer attachment to the Cu-O adhesion layer yields 30% higher bond strength compared to one containing Fe-O. Hence it may be speculated that macroscopic sliding wear behavior is determined by the bond strength between the molecular monolayer attachment and the intermediate metal-oxide adhesion layer (on tool steel).