Lubricated Friction of Rubber. VI. Portable Rebound Tester, with Particular Application to Wet Skid Resistance of Tires
Abstract An important conclusion from Part V of this series is that the wet skid resistance of a tire tread rubber is almost completely determined by its resilience and hardness, resilience being the more important variable. A useful feature of this relation is that both measurements are nondestructive and can be made, in principle, on a finished tire. Hardness is easily measured with commercially available instruments, such as the Shore Durometer, but a comparably useful instrument, one portable and suitable for use to measure resilience of finished and mounted tires, was not available. We have made and used such an instrument and have found additionally that it has features which make it useful for other purposes, notably measurement of resilience of very thin rubber specimens.