| Continuous carbon fiber reinforced aluminum matrix composites(Cf/Al)have excellent properties such as low density and high strength.In recent years,it has developed rapidly in the fields of aerospace,national defense,industrial facilities,transportation and sports.However,due to its micro-heterogeneity and macroscopic anisotropy,it is easy to appear more complex and serious machining damage in the machining process.This paper on the mesoscopic and macroscopic two dimension finite element simulation,and then on the geometry information of the fiber Angle grinding force theory analysis and simulation results to confirm each other,finally,the experimental results,simulation results and theoretical analysis were compared.The effects of grinding force,grinding mechanism,removing method of carbon fiber reinforced phase,grinding parameters and fiber Angle on grinding force,surface roughness Sa and surface/subsurface topography of Cf/Al composites were studied,and optimization of two kinds of grinding wheel grinding grinding process parameters of Cf/Al composite materials.It is mainly divided into the following three parts:(1)In order to study the grinding mechanism of Cf/Al composites and the removal method of carbon fiber,a three-dimensional meso-grinding simulation model based on a Representative Volume Element(RVE)model composed of fiber,interface and matrix was established.Different material constitutive,damage criterion and damage evolution are used for different phases.A VUMAT subroutine was used to redevelop the carbon fiber model,and the 3D linear elastic constitutive,3D Hashin failure criterion and damage evolution were defined.The JC model(Johnson-Cook)was used for the constitutive model and damage evolution of aluminum matrix materials,and the interface behavior was simulated by Cohesive force.Based on the anisotropy of macroscopic materials,a two-dimensional macroscopic grinding simulation model was established to study the influence of fiber angle and grinding parameters on the grinding subsurface damage depth.On the basis of these two finite element simulations,the grinding mechanism under different fiber angles and the effects of various grinding parameters and fiber angles on grinding force,surface topography and subsurface damage depth were studied.(2)Grinding parameters have great influence on the grinding force,surface roughness and surface/subsurface morphology of Cf/Al composites.In this paper,a single abrasive particle experiment and a single factor experiment of two kinds of grinding wheels(resin bonded diamond grinding wheel and electroplated diamond grinding wheel)were designed to grind Cf/Al composites under the same fiber Angle to study the influence of grinding parameters on the Cf/Al composites.A high-speed camera was used to observe the grinding process,collected the wear debris,observed the morphology,and summarized the grinding mechanism.The orthogonal experiment of two kinds of grinding wheels was designed to study the influence degree of various factors on grinding was and optimize the process parameter combination of two kinds of grinding wheels for Cf/Al composites.The grinding performance of two kinds of grinding wheels was compared from the factors of grinding force and surface quality.(3)The grinding force and surface/subsurface quality of Cf/Al composites are also greatly affected by different fiber angles under the same grinding parameters.In this paper,single particle experiments and single factor experiments were designed to study the effects of fiber angles on grinding force,surface roughness and surface/subsurface topography of a-plane and β-plane.The grinding mechanism of each fiber Angle was summarized,and a theoretical model of grinding force of Cf/Al composites was established according to the geometric relationship of β-angle.Combined with experiment,simulation and theoretical analysis,the grinding mechanism and carbon fiber removal method under each fiber Angle are summarized. |
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