Vibration damping capacity of a rotating shaft heat treated by various procedures

Abstract Many of today’s rotating shaft systems require the superior stability characteristics of a rotating shaft to prevent system instability. Rotating shaft material properties play a crucial role in the vibration behavior of rotating shaft systems. It is important to control vibrations in the systems because excessive vibration amplitudes can cause inefficiency and system failure. The objective of this study is to investigate the vibration damping capacity of a rotating shaft treated by various procedures (deep cryogenic treatment, induction hardening, hot forging, and conventional heat treatment) in order to see the effects of the treatment procedures. An AISI 4140 steel material for the rotating shaft was selected because it is the most widely used material in industry. The rotating shaft is supported on oil lubricated journal bearings rather than rolling element bearings as used in prior studies by the authors. The results showed that rotating shaft material damping capacity due to treatment processes plays a major role for the rotating shaft systems stability. It is observed that the vibration damping ability of the rotating shaft with induction hardening to dissipate mechanical vibration was superior to deep cryogenic treatment, especially to hot forging and conventional heat treatment processes. Also, the results indicate that the dynamics characteristics of the rotating shafts supported by oil lubricated journal bearings are different to those supported by rolling element bearings.