Cone Penetration Fracture of Metallic Thin Films: A Thermo-Mechanical Phase-Field and Experimental Study

Metal thin films, such as aluminum foil, are commonly used engineering materials with widespread applications in industries such as packaging and power batteries. When subjected to puncture by a metal cone, these films experience complex crack propagation phenomena. In-depth research into the crack formation and propagation process is significant for improving the understanding of the fracture mechanisms and performance control of metal thin films. Experimental results show that 15 micron aluminum foil may experience the propagation of 4–5 cracks during cone puncture. Since it is difficult to capture and analyze information on material deformation and stress in experiments, this study uses a thermo-elastic-plastic explicit phase field method to establish a numerical model for the puncture of aluminum foil by a metal cone, reproducing the fracture response and load-displacement process during the puncture. The computational results show good consistency with experimental results in terms of the final crack number and the force-displacement response during the loading process. Using the numerical model, the study also provides information on local plastic deformation zone during the puncture of aluminum foil by the metal cone. The proposal of this model will provide an important basis for in-depth research on the local mechanical response and key mechanical mechanisms during the aluminum foil piercing process.