<p>During high-speed cutting, the high strain rate (greater than 10⁴/s) can significantly impact the mechanical properties of the material, making its mechanical behavior distinct from traditional cutting. Hence, it is essential to establish the material flow characteristics of aluminum alloy 6005A at different strain rates ranging from 10^–4 to 5 × 10⁴/s. The power law constitutive model within the range of 10^–4 to 2.869 × 10³/s is obtained through regression of the data from alignment static tensile tests and Split-Hopkinson Pressure Bar tests. A full-factor simulation study of the constitutive model parameters in the range of 5 × 10³ to 5 × 10⁴/s is conducted using the finite element analysis method. Based on the finite element calculation results, the cutting force regression model with high strain rate constitutive model parameters is fitted, and a fitness function of the root mean square error between the theoretical value of the cutting force regression model and the experimental value of the cutting force is established. The optimal high strain rate constitutive model parameters are obtained through genetic algorithms, and the power-law constitutive model (covering a strain rate range of 10^–4 to 5 × 10⁴/s) is verified by experiments. The results indicate that the fitting results of the strain hardening coefficient and low strain rate sensitivity coefficient are 17.735 and 48.81 respectively. When the high strain rate sensitivity coefficient is 135.77 and the strain rate at which the transition between low and high strain rate sensitivity occurs is 26,134/s, the root-mean-square error between the finite element calculation result and the milling force test value is the smallest, with a value of 8.957. Experimental results show that the identified power law constitutive model has high prediction accuracy for milling force, chip shape, and chip thickness. It can be seen that the combination of finite element simulation and cutting experiment based on genetic algorithms can effectively describe the strain hardening and strain rate sensitivity characteristics of materials under high strain rates, thereby providing a more accurate basis for the cutting force prediction in high-speed cutting.</p>