Temperature field analysis for automated placement with thermoplastic composites based on the line-focused infrared heater

Infrared heating is one of the most prevalent heat sources utilized in automated fiber placement (AFP), particularly in the context of thermoset composites and the preheating of thermoplastic composites. Traditional infrared heaters often struggle to achieve concentrated heating in these applications. This paper employs a line-focused infrared heater (LIRH) in AFP. A dynamic finite element model was developed using ANSYS to investigate heat transfer during the layup process, and the interrelationship between temperature, laying speed, and LIRH power. The impact of tooling temperature on the cooling rate during layup was also analyzed, and an online measurement system for the temperature field was established. AFP is experimentally performed to analyze the heating performance of the LIRH to determine its relevant parameters. The results of both experiments and simulations indicate the prepreg bundle can achieve temperatures exceeding 400°C at a laying speed of 30 mm/s, with an infrared power setting of 1400 W and a tooling temperature of 50°C. The heat primarily emanates from the focused area of the LIRH, although a minor heating effect is observed from the unfocused infrared light. This research demonstrates the feasibility of employing LIRH for automated placement, particularly from the standpoint of temperature field.