Characterization of Engine Mount Elastomers
Abstract
As part of a project to develop methods for modelling the performance of engine mounts, several oil resistant alternative materials were prepared, and compared to conventional materials from mounts that are currently in service on the Canadian Patrol Frigate (CPF). This report describes the preparation and characterization of these elastomers, including two that were prepared at Platform Sciences Laboratory (PSL) in Melbourne, Australia under the Canada/ Australia MOU on Defence Science and Technology, Subsidiary Arrangement No. 16, Vibration Isolation Materials For Naval Vessels. The dynamic mechanical properties of the elastomers were determined as a function of frequency and strain amplitude. At strain amplitudes > 400 micrometers the storage moduli were generally independent of amplitude, once the moduli were corrected for changes in sample cross-sectional area resulting from tensile pre-strain. The storage moduli at 1 Hz, 20 deg C were in the range 3-7 MPa. The loss factors of the elastomers at 1 Hz, 20 deg C varied considerably, from 0.02 for natural rubber to 0.27 for ethylene acrylic elastomer. Swelling experiments of the elastomers in diesel fuel and lubricating oil demonstrated that the two elastomers prepared by PSL were in fact quite resistant to hydrocarbons. However, the hydrocarbon compatibility data for nitrile rubber/ plasticized PVC blend suggest that some plasticizer leaching occurred on exposure to lubricating oil. The frequency-dependent dynamic mechanical properties of the elastomers presented in this report were used in VAST Finite Element models of engine mounts, and in VVES models of engine vibration isolation systems. Hydrocarbon compatibility experiments suggest that ethylene acrylic elastomer would be a suitable replacement for natural rubber and neoprene rubber in engine mounts where exposure to hydrocarbon fluids is a concern.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 2005
- Accession Number
- ADA436285
Entities
People
- Jeffrey P. Szabo
Organizations
- Defence Research and Development Canada