SURFACE INTERACTIONS AND LUBRICATION RESPONSE OF SILICON NITRIDE BEARING ELEMENTS. FINAL REPORT NOVEMBER, 1972-NOVEMBER, 1973.

THE REPORT SUMMARIZES RESULTS OF A FUNDAMENTAL INVESTIGATION OF THE SUITABILITY OF SILICON NITRIDE AS A ROLLING BEARING MATERIAL WITH EMPHASIS ON ITS INTERACTIVE BEHAVIOUR WITH LUBRICATING FLUIDS.THE NEED FOR A LIGHT-WEIGHT BEARING MATERIAL IN CRITICAL HIGH-SPEED TURBINE APPLICATIONS IS DISCUSSED AND THE POTENTIAL BENEFITS OF SILICONE NITRIDE IN PARTICULAR ARE REVIEWED.THE WETTABILITY CHARACTERISTICS OF SIX LUBRICANTS ON A SILICONE NITRIDE SURFACE WERE MEASURED TO DETERMINE WHICH LUBRICANTS ARE APT TO BE SUCCESSFUL WITH SILICON NITRIDE BEARING COMPONENTS IN PERMITTING THE REPLENISHMENT OF LUBRICANT ONTO THE ROLLED-OVER TRACKS WHICH IS VITAL FOR THE MAINTENANCE OF AN ELASTOHYDRODYNAMIC FILM AND THE CONSEQUENT PREVENTION OF SURFACE INITIATED FATIGUE.(FROM AUTHORS' ABSTRACT).