Numerical simulation of aluminum alloy 6061 micro-mold fabrication for the production of polymeric microstructures by micro-hot-embossing

Micro-molds play an important role in the manufacturing process of polymeric micro-devices, e.g. microfluidic devices, as they determine the product quality and the overall production cost. We report here the applicability of a large-deformation, high-temperature, isotropic elastic-viscoplasticity model for the prediction of micron-scale hot-embossing of AA6061. The material parameters in the constitutive model were determined by fitting the stress-strain curves from compression tests at various temperatures and strain rates. The constitutive theory was implemented in a finite element program, and the numerical simulation capability was validated by predicting the response of AA6061 in some representative macro-scale experiments; these experiments had not been used for the determination of the material parameters in the constitutive model. Additional micron-scale hot-embossing experiments on AA6061 were conducted, and by comparing the numerical simulation results to the corresponding physical experiments, we demonstrate that the deformation evolution of AA6061 during micro-hot-embossing is well predicted. The constitutive model and its numerical implementation open the possibility of optimizing the process of making micro-molds for microfluidic devices from AA6061.