Title

Interactions Between Friction-Induced Vibration and Wear

Description

The interactions among friction, wear, and system
dynamics have been investigated for dry sliding contact between a steel pin and a cast iron disk. The system was equippedwith force and displacement transducers to measure the contact forces and the displacements in three directions. As the normal load increased, four different regimes were observed, the steady state friction regime, the nonlinear friction regime, transient friction regime, and the self-excited vibration regime. The last regime is characterized by periodic oscillations of the slider and high wear rate. The experimental setup was modified for further detailed study of this regime. The recorded wave forms showed that the oscillations consist of a fundamental harmonic with a frequency close to the sytem natural frequency in torsion and its second harmonic. A mathematical model was developed for the sytem including the coupling between the different degrees of freedom and a nonlinear contact stiffness, and the model was analyzed using triple input describing functions to include the constant, fundamental, and second harmonics. The model showed the existence of limit cycling at a freqency close to the torsional frequency of the system with amplitudes close to those observed experimentally. The results of this study enhance our understanding of friction induced vibrations and interactions which give rise to instability.

Creator

D'Souza, A. F.

Aronov, V.

Kalpakjian, S.

Shareef, I.

Dweib, A. H.

Date

1985

Date Issued

1985-01

Extent

45

Corporate Author

Illinois Institute of Technology

Laboratory

U. S. Department of Energy

Report Number

DOE/ER/12071-2

Contract

DE-AC02-82ER12071

NTRL Accession Number

DE85007696

Distribution Conflict

No

Photo Quality

Not Needed

Distribution Classification

1

Report Availability

Full text available

Abstract

The interactions among friction, wear, and system
dynamics have been investigated for dry sliding contact between a steel pin and a cast iron disk. The system was equippedwith force and displacement transducers to measure the contact forces and the displacements in three directions. As the normal load increased, four different regimes were observed, the steady state friction regime, the nonlinear friction regime, transient friction regime, and the self-excited vibration regime. The last regime is characterized by periodic oscillations of the slider and high wear rate. The experimental setup was modified for further detailed study of this regime. The recorded wave forms showed that the oscillations consist of a fundamental harmonic with a frequency close to the sytem natural frequency in torsion and its second harmonic. A mathematical model was developed for the sytem including the coupling between the different degrees of freedom and a nonlinear contact stiffness, and the model was analyzed using triple input describing functions to include the constant, fundamental, and second harmonics. The model showed the existence of limit cycling at a freqency close to the torsional frequency of the system with amplitudes close to those observed experimentally. The results of this study enhance our understanding of friction induced vibrations and interactions which give rise to instability.

Provenance

IIT

Type

report

Format

45 pages ; 28 cm.

Date Modified

Scanned and posted 2023-10-11