The infrared radiation is often supplied by high-intensity, quartz, heat lamps, producing radiation with wavelengths around 1 micron. When this radiation is applied to a polymer, melting occurs. In one mode of operation, the lamps are removed after melting has occurred, and the parts are forged together, as with hot plate welding. Infrared is particularly promising for higher melting polymers since the parts do not contact the heat source. Another potential advantage of infrared welding is speed.
Infrared radiation can penetrate into a polymer and create a zone of melt quickly.
By contrast, hot plate welding involves heating the polymer surface and relying on conduction to create the required melt zone. As might be expected, however, the depth of penetration depends on many factors, and it varies strongly with only minor changes in polymer formulation. All Rights Reserved.