The foundation of ball-milled iron castings is a box-shaped structure, and many strong ribs have been added. Some parts of ball-milled iron castings, such as guide rail surfaces, shaft holes and T-slots, are thicker, except for shrinkage holes and shrinkage. In addition to looseness, because the performance of ball milled iron castings is more sensitive to wall thickness, it is easy to loosen the structure at the place, the graphite is coarse, the hardness is low, and it is not wear-resistant. When the thickness of this part is too different from the surrounding connecting wall, it is not easy to produce crack defects. Due to the development of the cutting process of ball-milled iron castings towards automation, high-speed and powerful cutting, the emergence of CNC machine tools has caused some changes in the structure of ball-milled iron castings and brought some casting process problems. Regarding the defects and positions of ball milled iron castings, after analyzing the above problems, based on the above one problem, when designing ball milled iron castings, a reasonable structure of ball milled iron castings can be designed.