Abstract

In laser forming, phase transformations in the heat affected zone take place under steep cooling rates and temperature gradients, and have a significant affect on the laser forming process and final mechanical properties of products. In this work, phase transformations during laser forming of AISI 1010 steel are experimentally and numerically investigated and the transient volume fraction of each available phase is calculated by coupling the thermal history from finite element analysis with a phase transformation kinetic model. Consequently, the flow stresses of material are obtained from the constitutive relationship of the phases, and the laser forming process is modeled considering the effect of work hardening, recrystallization and phase transformation. A series of carefully controlled experiments are also conducted to validate the theoretically predicted results.

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