4. Significance and Use
4.1 Compression set tests are intended to measure the ability
of rubber compounds to retain elastic properties after prolonged
action of compressive stresses. The actual stressing
service may involve the maintenance of a definite deflection,
the constant application of a known force, or the rapidly
repeated deformation and recovery resulting from intermittent
compressive forces. Though the latter dynamic stressing, like
the others, produces compression set, its effects as a whole are
simulated more closely by compression flexing or hysteresis
tests. Therefore, compression set tests are considered to be
mainly applicable to service conditions involving static
stresses. Tests are frequently conducted at elevated temperatures.