Carbon fiber reinforced polymers (CFRP) are used in the field of aerospace due to their superior properties. At present

the researches on CFRP cutting mainly focus on single milling

but the multiple milling strategies are widely used in actual machining

the influence of multiple milling on subsurface damage cannot be ignored. In order to make up for this gap

VUMAT subroutine is used to establish three-dimensional Hashin failure criterion and CFRP multiple milling finite element model. The accuracy of the simulation model is verified by experiments. The model is used to analyze the variation of cutting force and surface damage with fiber direction angle (0°

45°

90°

135°). The results show that the cutting force of the second milling is less than the first milling in the multiple milling strategies

and the cutting force follows the rule of 90°135°45°0°. The subsurface damage is lower than that of single milling

and the damage factor increases with the increase of fiber direction angle. When the fiber direction angle is 0

the damage factor is the smallest

and the fiber direction angle is 135°

the damage factor is the largest

the subsurface damage is the most serious.