Performance Assessment and Study of Tribological Properties of Self-lubricating Materials for Dry Lubrication
P. N. L. Pavani†*, R. PolaRao†, C. L. V. R. S. V. Prasad†, & S. Srikiran‡
‡ Department of Mechanical Engineering, Lendi Institute of Engineering and Technology, Vizag-Viziangaram Road-NH-43, Denkada Mandal, Jonnada, Andhra Pradesh 535005, India
ABSTRACT: Application of lubricant is a problem in many cases, apart from external lubrication; it is always being useful if the material itself has self-lubricating properties. Such kind of materials are GCI & PTFE+Graphite composites. In these, Graphite flakes acts as solid lubricant & when load is applied, these layers slide over another & provide lubrication. PTFE+Graphite is well known for its self-lubricating properties and widely employed in applications, where dry lubrication & good thermal stability are needed. Primary aim of this work is to study & compare tribological properties of proposed self-lubricating materials. Tests are conducted on the POD apparatus using GCI disc and pin & PTFE+Graphite pin & AISI 1045 Steel disc specimens under different conditions. Later, linear Regression models are developed using input and output variables for both GCI Pin on GCI disc and PTFE filled with Graphite Pin on AISI 1040 Steel disc. Validation of the proposed mathematical equation was done by comparing experimental and predicted values of the experimentation and in all cases percentage error was found in between 0-6%. ANOVA was also performed on the experimental results to assess the conformity of the suggested mathematical model with 99% confidence levels.
Keywords : Friction; Wear; POD; Gray cast iron; PTFE; COF.
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