Measurement of Frictional Stick-Slip Transitions for Various Elastomeric Materials Sliding against Hard Counterfaces

The focus of this research was to determine the conditions under which friction induced vibration occurred in elastomeric sliding. Various elastomers were tested against chromium oxide and glass in an elastomeric hemisphere-on-flat configuration. Four regimes of oscillatory sliding were identified: 1. Steady state sliding were the sliding friction is constant; 2. A low frequency self-excited oscillation due to the natural frequency of the elastomer; 3. A high frequency self-excited oscillation due to the natural frequency of the test apparatus independent of the elastomer natural frequency; 4. Stick-slip motion of the elastomer. It was found that the friction-velocity curves reached a plateau in the coefficient of friction in the same decade of velocity (v= 10⁰- 10¹ mm/s). Previous theories and experimental results predict that the friction will go through a maximum at a velocity related to the glass transition temperatures or the loss modulus.