Mark Allan Lamontia

A Non-Isothermal Process Model for Consolidation and Void Reduction during In-Situ Tow Placement of Thermoplastic Composites

In in-situ composites processing, heat and pressure are applied locally to composite tows to achieve consolidation. During the consolidation of thermoplastic composite tows or plies, a modest amount of flow takes place. Due to the high viscosity of thermoplastics, the fibers and the matrix move together. We propose a novel approach to model this process-approximate the medium as a compressible viscous continuum rather than use Darcys law which has been successful in modeling thermoset composites processing. The void content of the composite changes during the consolidation process due to various mechanisms. A consolidation model for thermoplastic composite that incorporates—the relevant void growth and transport phenomena has been developed. The model is capable of predicting the final void fraction and the final thickness of a composite part as a function of the processing speed and the consolidation pressure under non-isothermal conditions.

Bearing mount system for reducing vibration

A bearing mounting system and method that reduces vibration using a singular annular elastomeric member contained in a substantially enclosed area that includes open area free of elastomeric material. A bearing raceway surface and an adjacent support surface are spaced apart by a predetermined radial gap. The enclosed cross-sectional area is bounded by features on the bearing raceway surface and the supporting surface that could be either the rotating roll or a support shaft. The enclosed area has a depth and a width and includes the radial gap. The viscoelastic deformation of the elastomeric member contained in this enclosed area in conjunction with the amount of open area in the enclosed area, provides a dual stiffness system that reduces or eliminates the excessive vibration that occurs in chucks for textile fiber windups or similar systems, when there is relative movement to reduce the radial gap and the enclosed area containing the radial gap.