Control loop tuning by thermal simulation applied to the laser transformation hardening with scanning optics process

Abstract

Laser transformation hardening with scanning optics (LTHS) is a novel manufacturing process on a very preliminary stage of introducing it in the surface treatment industry. The key to ensure the success in this process is the control of the process temperature. Thus, in this article, a close loop temperature control for LTHS process has been developed, tuned and tested in complex parts. On the one hand a PID temperature control has been implemented in a laser machine-tool. On the other hand, the same temperature control has been programmed in a numerical simulation software for LTHS process. In order to minimize experimental work, by means of using a novel method, the control constants have been tuned by means of thermal simulations. This method has been validated by comparing the results of the variation of different parameters in both cases, real and simulated. To complete the work, as the last test of the developed temperature control, different complex parts representing hardened parts for the automotive industry have been hardened with the developed system.