#Long path tool crack series#

The cohesion element method can be used to simulate the fracture behavior of materials. Cohesion refers to the interaction between atoms or molecules in matter.

#Long path tool crack series#

characterized the microstructure of single-phase alumina ceramic tool materials by Voronoi tessellation, and made a series of simulations related to crack propagation. The Voronoi tessellation is composed of some polygons similar to the material grain geometry, which can be used to characterize the microstructure of ceramic materials. The finite element method (FEM) is a numerical analysis method based on variational and interpolation principles. Therefore, it is of great significance to study the toughening mechanism of micro-interface and nano-interface by establishing the mechanical model of the interface between graphene and ceramic matrix. The graphene characteristic size, interface structure, and interface bonding strength play an important role in improving the mechanical properties of graphene toughened ceramic materials. At present, the macro toughening mechanisms of graphene have been mostly studied, such as crack deflection, graphene pull-out, and graphene fracture, while the micro and nano interface toughening mechanism of graphene is seldom studied. showed that the network structure formed by graphene in the ceramic matrix can enhance the interface bonding, leading to more crack bridging and deflection. found that fracture and pull-out of graphene would lead to more crack deflection and crack branching. used nano zirconia and graphene nano-sheets to toughen alumina ceramic composite, and it was reported that the fracture toughness increased by 155% and the microhardness increased by 17% compared with the monolithic alumina ceramic. added WC, TiC, and graphene into Al 2O 3 matrix to obtain Al 2O 3/WC/TiC/graphene composite ceramic tool materials, whose optimal indentation fracture toughness, Vickers hardness, and flexural strength reached 9.42 MPa.m 0.5, 24.64 GPa, and 646.31 MPa, respectively. In recent years, graphene toughened ceramic composite materials have been widely studied. Graphene has a high specific surface area and can be closely combined with ceramic matrix, which can improve the fracture toughness of ceramic materials. The reinforcing phases are usually boride, oxide, carbide, and so on. In order to improve the toughness of pure alumina ceramic materials, reinforcing phases are usually added into ceramic materials. However, pure alumina is very brittle, and it is prone to fracture. It is proven that the simulation results are in good agreement with the experimental phenomena.Д¬eramic materials have attracted attention because of their high hardness and wear resistance, and alumina ceramics are the most widely used thanks to their better oxidation resistance and low price. When the velocity load is 0.005 m s в€’1, the simulation result is convergent. When the volume content of graphene is 0.50 vol.%, the average energy release rate reaches the maximum.

When the phase interface is strong, the average energy release rate is the highest as the short diameter of graphene is 50вЂ“100 nm and the long diameter is 800вЂ“1200 nm. When the phase interface is weak, the average energy release rate is the highest as the short diameter of graphene is 10вЂ“50 nm and the long diameter is 1600вЂ“2000 nm. The effects of graphene characteristic size and volume content on the crack propagation behavior of microstructure model of alumina/graphene composite ceramics under different interfacial bonding strength were studied.

In this paper, the Voronoimosaic model and the cohesive element method were used to simulate crack propagation in the microstructure of alumina/graphene composite ceramic tool materials.