Interfacial effect between graphite and iron substrate on basal plane orientation and lubricity of graphite. (November 2020)

• Record Type: Journal Article
• Authors: Motozuka, Satoshi; Sato, Hisashi; Muramatsu, Yasuji; Morinaga, Masahiko
• Is Part Of: Tribology international. Volume 151(2020)
• Publication Date: 2020-11
• Subjects: Graphite -- Powder -- Lubricated -- Boundary; Tribology -- Periodicals; 621.89
• DOI: 10.1016/j.triboint.2020.106455
• Languages: English
• ISSNs: 0301-679X

Abstract

Abstract: The role of graphite/substrate interface in low-friction behavior of graphite was investigated. Iron and graphite powder mixtures were plastically deformed in either Ar–H2 or air atmospheres to obtain bare iron or iron oxide surface. Then, graphite particles adhered to and formed interfaces with surfaces. Friction force microscopy revealed that friction on particle surface milled in Ar–H2 atmosphere was obviously higher. X-ray absorption near-edge structure and transmission electron microscopy revealed that although the basal plane of graphite oriented along the oxidized surface, it did not occur along the bare iron surface, which explains the difference in lubricity on each surface. Graphical abstract: Image 1 Highlights: Graphite/bare iron and graphite/iron oxide interfaces prepared by ball milling process in either Ar–H2 and air atmospheres. Graphite worked as a lubricant on iron oxide surface, not on bare iron surface. Experiments using X-ray absorption near edge structure and transmission electron microscope revealed that the difference in graphite lubricity is due to basal plane orientation on each surface. Interfacial effect between graphite and iron substrates is likely vital in determination of graphite orientation on substrates.