R Gnanamoorthy

Fretting wear is a low amplitude reciprocating sliding wear that is observed in many machine elements. Effect of post oxidation on fretting wear behaviour of liquid nitrided structural steel, En 24, against the hardened and tempered En 31 steel was investigated. Oxidation treatment carried out at a temperature of 773 K leads to formation of stable oxide layer over the compound layer. The oxide layer mainly consists of magnetite (Fe3O4) and hematite (Fe2O3) phases. Fretting wear studies were carried out using cylindrical specimens at constant slip amplitude 60 μm and at different normal loads. The coefficient of friction against number of run was plotted. The effect of post oxidation duration on fretting wear behavior was reported in the form of fretting wear loss and friction coefficient. The thickness of oxide layer formed affects the friction and wear characteristics under fretting conditions. © 2005 Elsevier B.V. All rights reserved.

Fretting wear characteristics of Molybdenum disulphide (MoS2)-bonded solid lubricant coating on structural steel, AISI 4340, when fretted against hardened-tempered bearing steel, AISI 52100 are reported in this paper. Fretting wear tests were conducted at different normal loads and at constant slip amplitude of 60 μm. Coefficient of friction under fretting conditions and wear resistance were measured. The MoS2-bonded solid lubricant offers improved fretting wear resistance against bearing steels. Substrate hardness has influenced the coating behaviour at high loads. The fretting wear resistance also depends upon the normal load and the nature of contact, stick slip, or gross slip. © IMechE 2007.