Study on Antifatigue Crack Growth Characteristics of Ball-End Milling Bionic Surface

The surface morphology of parts has an important influence on service performance, such as wear resistance, fatigue resistance, and corrosion resistance. For example, the fatigue fracture resistance of the surface of the automobile cover mold directly determines the quality of the workpiece and the service life of the mold. In nature, the pit-shaped non-smooth form of the surface of certain organisms has good fatigue resistance. Using laser processing and other methods to prepare a pit-shaped bionic non-smooth surface on the surface of the part is an effective method to improve the fatigue resistance of the mold surface. Ball-end milling can form a regularly distributed pit-like surface morphology, and has the advantages of high processing efficiency, wide operating range, and low production cost compared with those of laser processing and preparation technology. It provides a new processing method for efficient milling preparation of bionic surfaces. In this paper, the morphology of the quadrilateral pits on the surface of the dung beetle is used as the prototype of the bionic design, and the mechanism of the antifatigue crack propagation characteristics of the quadrilateral pits of the bionic dung beetle is revealed and analyzed. The fatigue crack growth has a good retarding effect. At the same time, through numerical simulation and experimental research on the fatigue crack growth characteristics of the surface of the bionic pit, the results show that the source of fatigue cracks often starts inside the surface of the processed bionic pit, and the surface of the quadrilateral pit on the surface of the bionic dung beetle has good antifatigue crack growth characteristics.