This report describes experiments on friction of Si3N4 and SiC sliding against themselves and against each other in water at room temperature. The friction coefficient of Si3N4 against itself is f = 0.7 at low speeds (0.2 cm/s). At speeds above 6.5 cm/s and 4.91-N load, hydrodynamic lubrication sets in, with f = <0.002 and an estimated water film thickness of 70 nm. Between 0.2 and 5 cm/s, mixed lubrication occurs. This remarkably thin hydrodynamic film is made possible by the tribochemical wear of Si3N4 which occurs by dissolution in water and an absence of wear particles. The friction coefficient of SiC, against SiC or Si3N4 in water at low speeds is f = 0.26. Wear occurs by dissolution and fracture pitting. Small wear particles are observed. The friction coefficient of SiC against SiC is independent of sliding velocity between 0.2 and 20 cm/s. Hydrodynamic lubrication is obtained with a Si3N4 pin on SiC plate near 10 cm/s, mixed lubrication is obtained with a SiC in on Si3N4 plate at v < 20 cm/s. Prese...

Friction and Wear of Silicon Nitride and Silicon Carbide in Water: Hydrodynamic Lubrication at Low Sliding Speed Obtained by Tribochemical Wear

Technological Advances in Fine Abrasive Processes

Foreword Preface Introduction Introductory Mechanics Approaches to Solid Friction Measuring Friction in the Laboratory Fundamentals of Sliding Friction Solid Friction of Materials Lubrication to Control Friction Effects of Tribosystem Variables on Friction Running-In and Other Friction Transitions Applications of Friction Technology Index

Friction science and technology : from concepts to applications

Surface chemistry and tip-sample interactions in atomic force microscopy

http://content.stockpr.com/amedica/db/265/827/pdf/paperg.pdf

H. Tomizawa

Papers

Interaction of tribochemistry and microfracture in the friction and wear of silicon nitride