Modeling And Damage Prediction Of Coated Carbide Tool In Cutting Process Based On Discrete Element Method

Coated carbide tools combine the high strength of the substrate material with the high hardness of coating materials, it has been used in many mechanical manufacturing fields, such as turning, milling, drilling, and it plays an important role in dry cutting and high-speed cutting fields. However, the coating and the substrate have different elasticity modulus and different coefficient of thermal expansion,that would be lead to some cracks in the coating when the tools suffer the shock, and even leading the coating failure. In this paper, a discrete element model of TiCN coated carbide tool was established. Several different conditions of cutting processes were carried out to investigate the crack’s propagation and damage of coated carbide tool, and the influence of cutting parameters to the coated carbide tool’s crack propagation and damage were also predicted. The main research contents are as follows:1. The background and significance of this paper have been introduced at first. The research status of the performance of coating cutting, the application of DEM in Brittle cutting field and tools wear have been discussed.2. Then a discrete element model of coated cemented carbide tool has been established. According to the physical property of this tool, we choose proper geometry parameter for the DEM model. We use the parallel bond connect the particle in substrate and coating, and choose the displacement softening model describe the interface of coating tools.3. The DEM model of the coated carbide tools has been calibrated. Base on numerical tests, such as uniaxial compression test, three point bending test and fracture toughness test, the microscopic parameters of substrate material in DEM model has been calibrated at first. Then starching test have been used to calibrate the strength of interfacial bond between coating and substrate.4. Based on the DEM model which has been calibrated, the cutting processes of the coated carbide tool have been simulated by DEM. We can be carried out to investigate the process of the crack’s propagation and damage of coated carbide tool, the influence of cutting and production parameters to the coated carbide tool’s crack propagation and damage are also predicted.