Engineering Properties of RUBBER IN COMPRESSION..

DATA concerning the compression characteristics of rubber to aid engineers in incorporating rubber into their products are presented in this paper. Seven properties of rubber are defined: load deformation; stiffness; hardness; form factor; temperature factor; permanent set; and dynamic properties, including creep. Discussing hardness, the author charges that the generally used durometer method of measuring this property has “serious limitations and low accuracy” when applied to rubber, and announces that the

SAE is cooperating with the ASTM to improve this condition. Temperature curves, he points out, are not ordinarily required in design computations for rubber parts in motor cars since the rubber functions in a commercially acceptable manner through the range of temperatures to which the rubber is subjected in a motor car. A description of apparatus developed to measure the various properties of rubber includes dynamic performance-measuring and fatigue-testing equipment.