Methodology for wear mapping error quantification

Abstract

Purpose The purpose of this paper is to propose a methodology to quantify the error on wear volume evaluation using optical interferometry with image analysis (OI+IA), to establish a lower threshold for wear mapping in practical applications. Design/methodology/approach A three-dimensional surface wear map is quantified by measuring the same area of a surface before and after a wear process using optical interferometry. Then, by subtracting the matching images, the wear map (volume of wear) is obtained. To access the error related to wear mapping, the difference between several consecutive measurements of the same unworn surface was performed and deeply investigated. Findings The paper shows that the difference between two consecutive measurements of the same unworn surface, which ideally should be zero, is not. Thus, the magnitude of this “wear map” is the error. The main causes of such uncertainties are because of sample motion in a subpixel scale; a combination between surface roughness with the selected resolution; and numerical errors on the relocation process that is used to match the surfaces before subtracting them. Practical implications The proposed methodology allows one to define the lower threshold for wear map analysis using OI+IA. To know the limitation of OI+IA for wear mapping prevents misevaluation of the so-called almost-zero-wear. Originality/value This paper covers and identifies main uncertainties and numerical errors related to optical interferometry assisted by image analysis for wear mapping. Several other papers deal with uncertainties of OI; however, this paper proposes a simple methodology to evaluate the lower threshold for wear mapping. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0354

Effect of austempering treatment on lubricated sliding contact of compacted graphite iron

“…For helping the wear evaluation, the structure height (S3k = Spk + Sk + Svk), already used in previous investigations, especially for characterizing the so-called almost zero wear [14,[17][18][19][20][21][22], will be considered. In this study, the structure height decreased for the liners, in agreement with the flattening reported for honed surfaces.…”

Brazilian Tribology: origin, status quo and future perspectives

“…Finally, recently GrMaTS has focused on studying greases used in the wheel/rail pair [313,362] and labyrinth seals [314,315]. Besides, methodologies have been developed to investigate tribocorrosion of duplex stainless steels [316], to determine the kinetic friction in journal bearings [317], to assess particle abrasivity [318], and to identify the maximum resolution when measuring wear by optical interferometry [319]. In addition, this group contributed to this special issue by determining the tribological behaviour of nitrided and heat-treated ferritic stainless steel under diverse conditions [17].…”

A review of advances in tribology in 2020–2021

“…[378,379] respectively. Cousseau and Passos [380] discussed the methodology for wear mapping error quantification, and Kraus et al [381] proposed a test method for characterization of the contact pressue-dependent friction by using a single sheet metal compression test. The wear performances of 3D printed spur gears, made of Nylon 618, Nylon 645, alloy 910 filaments, together with Onyx and Markforged nylon proprietary materials respectively, were measured on a gear test rig [382], and it revealed that gears 3D printed using Nylon 618 actually performed better than injection moulded nylon 66 gears when low to medium torque was applied.…”