Abstract: In order to guarantee that a composite prepreg stay in a suitable process window for laying at any time, it is necessary to control the temperature of the prepreg accurately in automated tape-laying(ATL). High speed ATL process calls for a study of new efficienct heating manners and accurate control methods. This paper proposes an infrared heating method which is efficienct, and demonstrates a fast response rate. By analyzing the power transfer between the infrared heat source and the prepreg, the paper proposes calculation methods and equations about the transfer coefficients in the infrared heating process. Based on an analysis of the transfer coefficients, it establishes the temperature controlling equations of infrared heating for both the cases when the prepreg stays stationary and is moving, and through a comparision of the equations under the two different states, the paper proposes a concept of infrared radiation heating: the radiative ratio under steady state. By making use of the experimental data under the steady stationary state and the concept of the radiative ratio under steady state, and through theoretical deduction, the paper obtains the temperature controlling rule under a uniform motion running state. This may serve as a foundation for the application of infrared heating to ATL.

Key words: automated tape-laying (ATL), infrared heating, angle coefficient, radiative ratio under steady state, temperature control