Product Code: ICAL06_1709

Spring-Back Control in Laser Assisted Mechanical Forming of Dual Phase Steels
Authors:
Pablo M. Romero, AIMEN; Porriño Spain
German J. Rodriguez, AIMEN; Porriño Spain
Joaquin Vazquez, AIMEN; Porriño Spain
Jorge L. Arias, AIMEN; Porriño Spain
Presented at ICALEO 2006

Dual phase steels have become one of the most versatile materials, principally in high productivity industries as automotive industry. These steels offer improved mechanical properties, but a high spring-back effect is present in forming processes. AIMEN is working to develop a new mechanical laser assisted process in order to provide industry an efficient method to control and determine the parts final deflection. In this work, laser was used to produce a very controlled heating in C-shaped samples of different DP steels that provide us the required deformation. The experiments were carried out under a constant registration of temperature, deflection and strain. Both metallographic preparations and residual stress measurements were realized in order to understand the effects of simultaneous combination of mechanical and thermal loads. Two different high power laser sources, Nd:YAG and direct diode, were evaluated and compared to determine the convenience of both well-known lasers. In these experiments the spring-back effect was always successfully reduced without either critical thermal affectation or metallurgical transformations after laser applying. The obtained data were used as inputs to generate and validate a FE thermo-mechanical model that will lead us to a better understanding of the phenomena involved in DP steel laser assisted forming.