Autoclave-Free RF Lamination for Transparent Armor & Windows
Society for the Advancement of Material and Process Engineering
Long Beach, CA May 2011
Author: Shawn Allan
Co-authors: Morgana Fall, Inessa Baranova, Dr. Holly Shulman
Radio Frequency (RF) Lamination is a new patent applied for, energy efficient technology with promising results for eliminating the need for autoclaving in glass lamination. Laminated glass products including transparent armor, solar panels, and automotive and architectural windows, traditionally require the use of autoclaves. Autoclaving is typically the bottleneck of laminated glass production, and has several other drawbacks. RF heating dramatically decreases process time and energy by heating the plastic interlayer materials directly, rather than relying on thermal conduction through the glass structural layers. As a result, processes requiring several hours in an autoclave are reduced to a few minutes using RF. Demonstrations of RF lamination (FastFuse™) with the common interlayers, polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and thermoplastic urethane (TPU) are presented. Single layer and multilayer laminates, up to 8 cm (3.1”) thick were produced in process times ranging from 30 seconds to 5 minutes. RF laminated glass products were tested via standard methods including accelerated aging (bake and boil tests), adhesion peel tests, and ballistic impact testing and found to be equivalent to autoclave products. This work demonstrates feasibility and significant opportunities for out-of-autoclave manufacturing, not only for energy savings, but in expanding manufacturing for laminated glass and other composites.