A cutting simulation method for reinforced metal matrix composites based on phase field theory

Abstract

The present invention relates to a cutting simulation method for a reinforced metal matrix composite material based on phase field theory, which divides a workpiece material into three phases with different material mechanical properties, and performs cutting simulation on the workpiece material through mechanical dynamics, cutting principles, material failure mechanisms and finite element analysis. The present invention can not only accurately simulate the morphology of particles in a high-speed cutting process, but also can achieve surface roughness simulation. The modeling method is efficient, simple to operate, and reliable in results, and is of great significance to the cutting simulation of metal matrix particle composite materials.

Description

Technical Field

[0001] The invention relates to the technical field of reinforced metal matrix composite materials, and in particular to a cutting simulation method of reinforced matrix composite materials based on phase field theory. Background Art

[0002] Particle-reinforced metal matrix composites, as a widely used metal composite material, have the advantages of high strength, high hardness, strong fatigue resistance, wear resistance, low thermal conductivity, and small thermal expansion coefficient. They are widely used in aerospace, automobile manufacturing, military weapons, biomedicine and other fields. However, its high strength and high toughness mechanical strength, as well as the extremely hard ceramic reinforcement particles doped inside, add great difficulty to mechanical processing. Especially during the cutting process, the collision and scratching between the tool and the reinforcement particles further aggravate the process of tool wear. With the development of computer technology, the finite element simulation method has been widely used and replaced the traditional cutting test method to explore its cutting mechanism due to its high efficiency and low cost.

[0003] In the traditional simulation modeling method of metal matrix composite materials, only the metal matrix and reinforced particles are given mechanical strength and failure parameters, and the interface between the reinforced particles and the metal matrix is ​​simplified to an interface with a thickness of zero (or a single molecule interface), so the mechanical strength of the interface is ignored in the modeling process. In fact, the bonding surface of the composite material has a certain thickness (submicron), which is a new phase with obvious mechanical strength, structure and matrix difference - the interface phase. The mechanical strength of the interface phase determines the mechanical properties of the composite material to a certain extent, and also determines its machining performance. Therefore, in the traditional model, the peeling criterion between the particles and the matrix is ​​equivalent to the aging criterion of the metal matrix material to a certain extent, and thus cannot truly reveal the mechanism of the mutual influence between the matrix and the reinforced particles during the cutting process, resulting in errors in the simulation results. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a cutting simulation method for reinforced matrix composite materials based on phase field theory, which can give mechanical properties to the interface phase during the simulation process to ensure that the simulation result is consistent with the actual situation.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a cutting simulation method for reinforced metal matrix composite materials based on phase field theory, which divides the workpiece material into three phases with different material mechanical properties, and performs cutting simulation on the workpiece material through mechanical dynamics, cutting principles, material failure mechanism and finite element analysis.

[0006] More specifically, the steps of the cutting simulation method are:

[0007] S1. Establish a two-dimensional workpiece and tool model, and divide the workpiece material into three phases with different material mechanical properties, namely, a matrix phase, a particle phase, and an interface phase, wherein the interface phase is located between the matrix phase and the particle phase;

[0008] S2, assigning corresponding mechanical properties and material failure characteristic parameters to the matrix phase, particle phase and interface phase;

[0009] S3, establish the Young's modulus of the interfacial phase;

[0010] S4, defining the cutting parameters of the tool;

[0011] S5. Perform simulated cutting on the model established above to obtain simulated cutting results that take the interface phase into consideration.

[0012] More specifically, in step S1, the matrix phase is a metal matrix.

[0013] More specifically, the metal matrix is ​​a magnesium alloy or an aluminum alloy, and the particle phase is silicon carbide.

[0014] More specifically, the function of the Young's modulus of the interface phase in step S3 is,

[0015] Y = 100 + r × 1000,

[0016] Among them, Y is the Young's modulus of the interfacial phase, and r is the radius distance from any point on the particle to the center of the circle.

[0017] More specifically, the cutting parameters in step S4 are cutting thickness, cutting speed, tool rake angle, tool clearance angle and cutting edge radius.

[0018] More specifically, the cutting simulation method uses the commercial finite element simulation component Abaqus for simulation.

[0019] More specifically, the mechanical properties in step S2 are density, Young's modulus, compression ratio, specific heat capacity, thermal conductivity and compressive strength.

[0020] The beneficial effects of the present invention are: the present invention can not only accurately simulate the morphology of particles in the high-speed cutting process, but also realize the simulation of surface roughness. The modeling method is efficient, simple to operate, and has reliable results, which is of great significance for the cutting simulation of metal-based particle composite materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the simulation cutting modeling of the present invention;

[0022] Figure 2Schematic diagram of the change of Young's modulus of the interface phase in the present invention along the radial direction;

[0023] Figure 3 It is a schematic diagram of the relationship between the Young's modulus changes of the metal matrix, the interface phase and the particle phase of the present invention;

[0024] Figure 4 It is a schematic diagram of the simulation cutting process of the present invention;

[0025] Figure 5 The surface of the product with particles falling off obtained from the simulation results of the present invention;

[0026] Figure 6 The surface of the product obtained by actual cutting according to the present invention where particles have fallen off;

[0027] Figure 7 The surface of the product in which particles are embedded obtained from the simulation results of the present invention;

[0028] Figure 8 The surface of the product into which particles are embedded obtained by actual cutting of the present invention;

[0029] Fig. 9 The morphology of particle shedding is obtained by traditional cutting simulation method;

[0030] Fig.10 The cutting simulation method of the present invention obtains the morphology of particle shedding. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the implementation of the present invention clearer, the technical scheme in the embodiment of the present invention will be described in more detail below in conjunction with the drawings in the embodiment of the present invention. In the drawings, the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The described embodiments are part of the embodiments of the present invention, not all of the embodiments. The embodiments described below with reference to the drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limitations on the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0032] A cutting simulation method for reinforced metal matrix composites based on phase field theory. The cutting simulation method divides the workpiece material into three phases with different material mechanical properties, and simulates the cutting of the workpiece material through mechanical dynamics, cutting principles, material failure mechanisms and finite element analysis. A third phase is set between two phases to make it more close to the actual state, thereby being consistent with actual cutting during the simulation process.

[0033] Based on the above cutting simulation method, the steps of the cutting simulation method are:

[0034] S1. Build a two-dimensional model of the workpiece and tool (such as Figure 1 As shown in the figure), the workpiece material is divided into three phases with different material mechanical properties, namely the matrix phase, the particle phase and the interface phase. The interface phase is located between the matrix phase and the particle phase (as shown in the figure). Figure 2 As shown), the matrix phase is a metal matrix, which is a magnesium alloy or an aluminum alloy, the particle phase is silicon carbide, and the mechanical properties of the interface phase are between the matrix phase and the particle phase.

[0035] S2. Assign corresponding mechanical properties and material failure characteristic parameters to the matrix phase, particle phase and interface phase. The mechanical properties include density, Young's modulus, compression ratio, specific heat capacity, thermal conductivity and compressive strength.

[0036] S3, establish the Young's modulus of the interface phase (such as Figure 3 As shown), the function of the Young's modulus of the interface phase is,

[0037] Y=100+r×1000GPa,

[0038] Among them, Y is the Young's modulus of the interfacial phase, and r is the radius distance from any point on the particle to the center of the circle.

[0039] The Young's modulus of the corresponding matrix phase is 100 GPa; the Young's modulus of the corresponding particle phase is 400 GPa.

[0040] S4. Define the cutting parameters of the tool, which are cutting thickness, cutting speed, tool rake angle, tool back angle and cutting edge radius.

[0041] S5, simulate cutting the model established above (such as Figure 4 As shown in the figure), the simulation cutting results considering the interface phase are obtained.

[0042] The above cutting simulation method uses the commercial finite element simulation component Abaqus for simulation.

[0043] Enter the simulation parameters in Abaqus:

[0044] Table 1: Simulation model cutting parameters

[0045]

[0046] Table 2: Mechanical properties of matrix material (magnesium alloy) and Johnson-Cook model coefficients

[0047]

[0048] Table 3: Mechanical properties of granular materials (SiC) and Johnson-Cook model coefficients

[0049]

[0050] The following is an explanation combining the simulated cutting surface and the actual cutting surface.

[0051] During the cutting process, two main situations may occur:

[0052] 1. During the cutting process, the particles are peeled off from the raw material, that is, the particles fall off.

[0053] like Figure 5 As shown in the simulated cutting process, particles appear to fall off the product surface. It can be seen that as the tool feeds, many cavities are generated due to the falling of particles.

[0054] like Figure 6 As shown in the figure, during the actual cutting process, the surface of the product where particles fell off was observed through a microscope, and many cavities were also found, which is similar to the simulation results.

[0055] 2. When cutting metal-based particle composites, particles are often pressed into the metal matrix by the cutting edge, resulting in the embedding of particles into the metal matrix, i.e., particle embedding.

[0056] like Figure 7 As shown in the simulation cutting process, the particles are embedded in the product surface of the matrix. It can be seen that as the tool feeds, many protrusions are generated due to the embedding of the particles, and there are shallow cavities around each protrusion.

[0057] like Figure 8 As shown in the figure, during the actual cutting process, the particles are embedded in the surface of the matrix product. Through microscopic observation, many protrusions and shallow cavities surrounding the protrusions are also found, which is similar to the simulation results.

[0058] The following figures compare the traditional simulation method and the patented method when particles fall off.

[0059] like Fig. 9 and Fig.10 The particle shedding morphology obtained by the traditional method and the patented method is shown. It can be observed that in the traditional simulation method, once one of the cells around the particle reaches the failure standard, the particle will be separated from the surrounding matrix as a whole, but this does not conform to the actual cutting law. However, after using the simulation method based on phase field theory, when the cells around the particle reach the failure standard, only the failed grid will separate from the workpiece, and other cells that do not reach the failure standard will not peel off from the particle. Compared with the traditional simulation method, the results obtained by the innovative method are more in line with the cutting law.

[0060] In summary, the traditional simulation method of metal-based particle reinforced composite materials does not take into account the mechanical properties of the interface phase, and the failure of the particles often depends on the setting of the failure parameters of the matrix material itself, and it is impossible to truly simulate the shedding and breakage of particles during the cutting process. The present invention can not only accurately simulate the morphology of particles during high-speed cutting, but also simulate the surface roughness. The modeling method is efficient, simple to operate, and has reliable results, which is of great significance to the cutting simulation of metal-based particle composite materials.

[0061] It should be emphasized that the above are only preferred embodiments of the present invention and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A cutting simulation method for reinforced metal matrix composites based on phase field theory, characterized in that: The cutting simulation method divides the workpiece material into three phases with different material mechanical properties, and performs cutting simulation on the workpiece material through mechanical dynamics, cutting principles, material failure mechanism and finite element analysis. The steps of the cutting simulation method are: S1. Establish a two-dimensional workpiece and tool model, divide the workpiece material into three phases with different material mechanical properties, namely a matrix phase, a particle phase and an interface phase, wherein the interface phase is located between the matrix phase and the particle phase; the matrix phase is a magnesium alloy or an aluminum alloy, and the particle phase is silicon carbide; S2, assigning corresponding mechanical properties and material failure characteristic parameters to the matrix phase, particle phase and interface phase; S3. Establish the Young's modulus of the interface phase. The function of Young's modulus of the interface phase is, Y=100+r×1000, Among them, Y is the Young's modulus of the interfacial phase, r is the radius distance from any point on the particle to the center of the circle; S4, defining the cutting parameters of the tool; S5, performing simulated cutting on the model established above to obtain a simulated cutting result taking into account the interface phase body; The cutting parameters in step S4 are cutting thickness, cutting speed, tool rake angle, tool clearance angle and cutting edge radius; The mechanical properties in step S2 are density, Young's modulus, compression ratio, specific heat capacity, thermal conductivity and compressive strength.

2. The method for cutting a reinforced metal matrix composite material based on phase field theory according to claim 1, characterized in that: The cutting simulation method uses the commercial finite element simulation component Abaqus for simulation.

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