Multi-parameter autonomously adjustable liquid film shear polishing device and polishing method

Abstract

This invention provides a multi-parameter autonomously adjustable liquid film shear polishing device, including a base, a polishing disc module, and a workpiece clamping drive module. The workpiece clamping drive module includes a carrier disc for clamping the workpiece. A temperature sensor and a pressure sensor are located on the lower side of the carrier disc. A pH sensor is located on the wall of the polishing liquid tank. A pH adjustment module is located above the polishing liquid tank, capable of adding a pH adjuster to the polishing liquid tank. During polishing, the control module evaluates the current polishing pH value, polishing temperature, and workpiece pressure using a BP neural network model, then uses a genetic optimization algorithm to find the optimal polishing parameters, and finally autonomously adjusts the polishing parameters. This invention also provides a multi-parameter autonomously adjustable liquid film shear polishing method. By autonomously adjusting the polishing parameters, this invention effectively eliminates the instability caused by changes in the polishing environment during processing, achieving efficient, high-quality, and stable polishing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ultra-precision polishing, and more particularly to a liquid film shearing polishing device with multi-parameter self-adjustment and a polishing method realized by using the device. BACKGROUND

[0002] When the shear rate of a non-Newtonian fluid is greater than a certain critical value, shear rheological effect is formed, solid colloidal particles are polymerized into a large number of "particle clusters", the holding action on abrasive particles is enhanced, the abrasive particles are driven to polish the workpiece flexibly, and material removal is realized while mechanical scratches of hard large particles on the workpiece are avoided; in the polishing process, the rotation of the structured polishing disc generates a non-Newtonian fluid liquid film with high-speed shearing effect between the polishing disc and the workpiece, the liquid film shearing effect is formed, the horizontal shearing removal effect of the polishing liquid is enhanced, and efficient removal of the workpiece surface material is realized.

[0003] The addition of chemical effect can generate an oxide layer on the workpiece surface, and then soften the workpiece surface, and improve the liquid film shearing polishing removal efficiency. However, the PH value in the liquid film shearing polishing process under the chemical enhancement effect will change due to various factors, such as chemical reaction between the workpiece and the polishing liquid composition, volatilization of the polishing liquid composition, etc. At the same time, the changes of force and temperature between the workpiece and the polishing liquid will directly affect the shear rheological effect. The changes of PH value and shear rheological effect will directly affect the stability of the polishing process. At present, the polishing equipment can only set the initial polishing parameters by manual operation, and cannot solve the instability caused by the change of the polishing environment in the processing process, so that the workpiece after processing has a high rejection rate, and the overall polishing cost is high. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a liquid film shearing polishing device with multi-parameter self-adjustment and a polishing method realized by using the device. In the technical scheme of the present application, during polishing, the current polishing PH value, polishing temperature and workpiece pressure are evaluated by the control module through the BP network neural model, the optimal polishing parameters are found by the genetic optimization algorithm, and finally the polishing parameters are self-adjusted, so that the instability caused by the change of the polishing environment in the processing process is effectively eliminated, and efficient, high-quality and stable polishing processing is realized.

[0005] For the device, the technical scheme of the present application is as follows:

[0006] The multi-parameter self-adjusting liquid film shear polishing device comprises a base, a polishing disc module and a workpiece clamping driving module arranged on the base, the polishing disc module comprises a structured polishing disc and a polishing liquid tank, the polishing liquid tank is used for placing polishing liquid and can be driven to rotate by a polishing disc driving device, the structured polishing disc is fixedly arranged in the polishing liquid tank, the upper surface of the structured polishing disc is provided with wedge-shaped grooves arranged in a radial manner, the workpiece clamping driving module is arranged above the structured polishing disc and comprises a carrier disc used for clamping a workpiece, the carrier disc can be driven to rotate by a carrier disc driving device and can be adjusted in height, the lower side of the carrier disc is provided with a temperature sensor and a pressure sensor, the groove wall of the polishing liquid tank is provided with a PH sensor, a PH adjusting module is arranged above the polishing liquid tank, the PH adjusting module can add a PH adjusting agent into the polishing liquid tank, the PH adjusting module has two sets and is used for adding alkaline agents and acidic agents respectively, the temperature sensor, the pressure sensor, the PH sensor, the PH adjusting module, the polishing disc driving device and the carrier disc driving device are signal-connected with a control module, during polishing, the temperature sensor, the pressure sensor and the PH sensor detect the PH value of polishing liquid, the workpiece pressure and the polishing liquid temperature near the workpiece in real time, data are transmitted to the control module, the control module evaluates the current polishing PH value, the polishing temperature and the workpiece pressure through a BP network neural model, the optimal polishing parameters are found through a genetic optimization algorithm, and finally the polishing parameters are self-adjusted.

[0007] Compared with the prior art, the multi-parameter self-adjusting liquid film shear polishing device can detect the PH value of polishing liquid, the workpiece pressure and the polishing liquid temperature near the workpiece in real time through the temperature sensor, the pressure sensor and the PH sensor during polishing, evaluate the current polishing PH value, the polishing temperature and the workpiece pressure through a BP network neural model by the control module, find the optimal polishing parameters through a genetic optimization algorithm, and finally self-adjust the polishing parameters, effectively eliminate the instability caused by the change of polishing environment during processing, thereby improving the yield of the workpiece after polishing and reducing the overall polishing cost.

[0008] Further, in the multi-parameter self-adjusting liquid film shear polishing device, the PH adjusting module comprises a liquid storage tank used for storing acidic and alkaline agents, the liquid storage tank is provided with a liquid inlet and a liquid outlet, the liquid inlet is used for adding agents, the liquid outlet is provided with a control valve and a liquid supply pump.

[0009] Further, in the multi-parameter self-adjusting liquid film shear polishing device, the polishing liquid tank is provided with a liquid discharge port, and the liquid discharge port is provided with a plug.

[0010] Further, the aforementioned multi-parameter self-adjusting liquid film shear polishing device, wherein the base is provided with a waste liquid tank, the polishing liquid tank is located in the waste liquid tank, and the waste liquid tank is communicated with the recovery container through a pipeline. This structure is easy to implement and very convenient to use.

[0011] For the method, the present application provides the following technical solutions:

[0012] The multi-parameter self-adjusting liquid film shear polishing method under the chemical enhancement effect is implemented by using the aforementioned multi-parameter self-adjusting liquid film shear polishing device of the present application.

[0013] Compared with the prior art, the liquid film shear polishing method of the present application is implemented by using the aforementioned multi-parameter self-adjusting liquid film shear polishing device of the present application, and the polishing parameters are self-adjusted during the polishing process, which effectively avoids the influence of changes in the polishing environment on the processing quality, realizes efficient, high-quality and stable processing, and reduces the defective rate of the workpiece after processing.

[0014] As an optimization, in the aforementioned multi-parameter self-adjusting liquid film shear polishing method, the polishing disc rotation speed, the workpiece rotation speed and the polishing time are input before polishing; the parameter self-adjusting process can be as follows: after starting polishing, the workpiece pressure, temperature and polishing liquid PH value are detected for the first time, and the initial comprehensive score Y1 is calculated through a BP neural network model; the workpiece pressure, temperature and polishing liquid PH value are detected in real time during the polishing process, the above parameters are evaluated through a neural network model to obtain an evaluation value Y2, Y2 is compared with Y1, if the floating range exceeds a set percentage, the optimal parameters are found through a genetic algorithm, and the polishing disc rotation speed, the workpiece rotation speed and the PH value parameters are regulated, and then the evaluation value Y2 is recalculated until the condition is met, and one regulation cycle is completed.

[0015] Further, the set percentage can be 0.4-1%.

[0016] Further, the liquid supply pump adds 2-3 ml of adjusting reagent to the polishing liquid tank each time.

[0017] Further, the aforementioned multi-parameter self-adjusting liquid film shear polishing method is used for polishing processing of tungsten alloy. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 The polishing parameter regulation and control flowchart in the technical solutions of the present application;

[0019] Figure 2 The overall structure schematic diagram of the multi-parameter self-adjusting liquid film shear polishing device of the present application;

[0020] Figure 3 The structure schematic diagram of the polishing disc module in the present application;

[0021] Figure 4 The structural diagram of the PH adjusting module in the present application;

[0022] Figure 5 The structural diagram of the carrier disc in the present application;

[0023] Figure 6 The processing result of the comparative experiment;

[0024] Figure 7 The processing result of the technical scheme of the present application.

[0025] The marks in the drawing: 1-stand, 101-waste liquid tank; 2-structured polishing disc, 201-wedge-shaped groove; 3-polishing liquid tank, 301-plug; 4-carrier disc; 5-temperature sensor; 6-pressure sensor; 7-PH sensor; 8-PH adjusting module, 801-liquid storage tank, 802-control valve, 803-liquid supply pump; 9-recovery container. DETAILED DESCRIPTION

[0026] The technical scheme of the present application will be further described below by specific examples, but not as the basis for limiting the present application. In the following examples, the contents not described in detail all belong to the technical common sense in the art.

[0027] Examples (see 1-7):

[0028] The multi-parameter self-adjusting liquid film shearing polishing device of the present application comprises a stand 1, and a polishing disc module and a workpiece clamping and driving module correspondingly arranged on the stand 1; the polishing disc module comprises a structured polishing disc 2 and a polishing liquid tank 3; the polishing liquid tank 3 is used for placing polishing liquid and can be driven to rotate by a polishing disc driving device; the structured polishing disc 2 is fixedly arranged in the polishing liquid tank 3; the upper surface of the structured polishing disc 2 is provided with wedge-shaped grooves 201 distributed in a radial manner in groups (the wedge-shaped grooves 201 can enhance the shear thickening effect); the workpiece clamping and driving module is arranged above the structured polishing disc 2, and comprises a carrier disc 4 used for clamping a workpiece, the carrier disc 4 can be driven to rotate by a carrier disc driving device and can be adjusted in height. The above settings belong to the prior art.

[0029] Different from the prior art is that:

[0030] The lower side of the carrier disc 4 is provided with a temperature sensor 5 and a pressure sensor 6, the groove wall of the polishing liquid tank 3 is provided with a PH sensor 7, the upper side of the polishing liquid tank 3 is provided with a PH adjusting module 8, the PH adjusting module 8 can add PH adjusting agents into the polishing liquid tank 3; the PH adjusting module 8 has two sets, which are respectively used for adding alkaline agents and acidic agents.

[0031] The temperature sensor 5, the pressure sensor 6, the PH sensor 7, the PH adjusting module 8, and the polishing disc driving device and the carrier disc driving device are all signal-connected with the control module (in the embodiment, the control module includes a console host and a PLC, the calculation is completed by the console host, and the polishing parameter adjustment is executed by the PLC) ; during polishing, the temperature sensor 5, the pressure sensor 6, and the PH sensor 7 perform real-time detection on the PH value of the polishing liquid, the workpiece pressure, and the polishing liquid temperature near the workpiece during polishing, and transmit data to the control module; the control module evaluates the current polishing PH value, the polishing temperature, and the workpiece pressure through a BP network neural model, then finds the optimal polishing parameters through a genetic optimization algorithm, and finally autonomously adjusts the polishing parameters. The three parameters of pressure, PH, and temperature influence each other, for example, the change of temperature will affect the change of PH, the addition of a PH reagent will directly affect the polishing liquid concentration, the shear effect will also change, and thus affect the force acting on the workpiece. The three parameters are comprehensively evaluated and uniformly adjusted in the application, so that the influence of the adjustment of one factor on the other two factors can be avoided.

[0032] The PH adjusting module 8 includes a liquid storage tank 801 for storing acid-base reagents, the liquid storage tank 801 is provided with a liquid inlet and a liquid outlet, the liquid inlet is used for adding reagents, and the liquid outlet is provided with a control valve 802 and a liquid supply pump 803. During polishing, the control valve 802 can be opened by the control module, and the liquid supply pump 803 is started to add PH adjusting reagents to the polishing liquid tank 3.

[0033] The polishing liquid tank 3 is provided with a liquid outlet, and the liquid outlet is provided with a plug 301. During polishing, the plug 301 is used to plug the liquid outlet, after polishing, the plug 301 is removed, and the polishing liquid is discharged, so as to facilitate cleaning of the polishing liquid tank 3.

[0034] The machine base 1 is provided with a waste liquid tank 101, the polishing liquid tank 3 is located in the waste liquid tank 101, and the waste liquid tank 101 is communicated with the recovery container 9 through a pipeline. The waste liquid tank 101 is arranged at the periphery of the polishing liquid tank 3, and is used for receiving the polishing liquid discharged from the polishing liquid tank 3, and then guiding the polishing liquid to the recovery container 9 through the pipeline.

[0035] Before polishing by using the multi-parameter self-adjusting liquid film shear polishing device, the polishing disc rotating speed, the workpiece rotating speed, and the polishing time are inputted.

[0036] In the polishing process, the parameter self-adjusting process is as follows: after starting polishing, the workpiece pressure, temperature and polishing liquid PH value are detected for the first time, and the initial comprehensive score Y1 is calculated through the BP neural network model; the workpiece pressure, temperature and polishing liquid PH value are detected in real time during the polishing process, the above parameters are evaluated through the neural network model to obtain the evaluation value Y2, Y2 is compared with Y1, if the floating range exceeds 0.4% (i.e. the absolute value of Y2-Y1 exceeds 0.4%*Y1), the optimal parameters are found through the genetic algorithm, and the polishing disc speed, workpiece speed and PH value parameters are adjusted, then the evaluation value Y2 is recalculated until the condition is met, and one adjustment cycle is completed. Specifically, in the embodiment, the BP neural network model takes the comprehensive evaluation value Y as the output neuron, and 5 neurons are selected in the intermediate hidden layer; the input layer neuron nodes are temperature, pressure and PH value; after the polishing experimental data are subjected to min-max normalization processing, the data are used as the training set data of the BP neural network and input into the network for network training. The training function is set to traingdx, the activation function adopts the sigmoid function, the learning rate is set to 0.001, and the root mean square target value is set to 0.001. When the BP neural network reaches the set root mean square target error requirement of 0.001, the training requirement is reached. The historical samples collected after being put into use can be used for regular training.

[0037] The liquid supply pump 803 adds 3ml of the adjusting agent to the polishing liquid tank 3 each time.

[0038] Through experiments, the present application can realize efficient, high-quality and stable polishing processing of tungsten alloy. Of course, the technical scheme of the present application can also be used for surface polishing of other materials.

[0039] In order to verify that the polishing method of the present application has stable and high-quality polishing effect compared with the non-self-adjusting polishing equipment, four tungsten alloy workpieces of the same size are polished by using the conventional liquid film shearing polishing equipment and the present application equipment respectively, and the initial conditions of the two equipment are consistent. The specific experimental conditions are as follows:

[0040]

[0041] After polishing, the polishing results of the tungsten alloy workpieces of the non-self-adjusting equipment are as shown in Figure 6 The surface roughness Ra of the four workpieces is more than 10 nm, and the fluctuation range is large, and the surface morphology is accompanied by undulation. The overall quality of the workpiece surface is low, and the morphology is quite different, which indicates the instability of the polishing process.

[0042] After polishing, the polishing results of the tungsten alloy workpieces of the self-adjusting equipment of the present application are as shown in Figure 7As shown, the roughness Ra of the four workpiece surfaces is all below 10 nm, and the surface topography is well improved with good undulation. The overall quality of the workpiece surface is improved, and the overall surface quality difference is small, representing that the stability of the polishing is obviously improved compared with the conventional polishing equipment.

[0043] The above-described embodiments are only to describe the preferred embodiments of the present application, and not to limit the concept and scope of the present application. Without departing from the design concept of the present application, various modifications and improvements to the technical solutions of the present application made by those skilled in the art shall fall within the protection scope of the present application, and the technical content claimed by the present application has been fully recorded in the claims.

Claims

1. A method of liquid membrane shear polishing with multi-parameter autonomous adjustment under the effect of chemical reinforcement, characterized in that: The method is realized by using a multi-parameter self-adjusting liquid film shear polishing device; the multi-parameter self-adjusting liquid film shear polishing device comprises a base (1), a polishing disc module and a workpiece clamping driving module which are arranged on the base (1); the polishing disc module comprises a structured polishing disc (2) and a polishing liquid tank (3); the polishing liquid tank (3) is used for placing polishing liquid and can be driven to rotate by a polishing disc driving device; the structured polishing disc (2) is fixedly arranged in the polishing liquid tank (3); a plurality of wedge-shaped grooves (201) which are distributed in a radial manner are arranged on the upper surface of the structured polishing disc (2) in groups; the workpiece clamping driving module is arranged above the structured polishing disc (2) and comprises a carrier disc (4) which is used for clamping a workpiece; the carrier disc (4) can be driven to rotate by a carrier disc driving device and the height thereof can be adjusted; a temperature sensor (5) and a pressure sensor (6) are arranged on the lower side of the carrier disc (4), a PH sensor (7) is arranged on the tank wall of the polishing liquid tank (3), a PH adjusting module (8) is arranged above the polishing liquid tank (3), the PH adjusting module (8) can add a PH adjusting agent into the polishing liquid tank (3); the PH adjusting module (8) has two sets which are respectively used for adding an alkaline agent and an acidic agent; the temperature sensor (5), the pressure sensor (6), the PH sensor (7), the PH adjusting module (8), the polishing disc driving device and the carrier disc driving device are signal-connected with a control module; during polishing, the temperature sensor (5), the pressure sensor (6) and the PH sensor (7) detect the PH value of polishing liquid, the workpiece pressure and the polishing liquid temperature near the workpiece in real time during polishing and transmit data to the control module; the control module evaluates the current polishing PH value, the polishing temperature and the workpiece pressure by a BP network neural model, finds the optimal polishing parameters by a genetic optimization algorithm and finally adjusts the polishing parameters automatically; the polishing disc rotating speed, the workpiece rotating speed and the polishing time are input before polishing; the parameter self-adjusting process is as follows: after starting polishing, the workpiece pressure, the temperature and the polishing liquid PH value are detected for the first time, an initial comprehensive score Y1 is calculated by a BP neural network model; the workpiece pressure, the temperature and the polishing liquid PH value are detected in real time during polishing, evaluation values Y2 are obtained by evaluating the above parameters by a neural network model, Y2 is compared with Y1, if the floating range exceeds a set percentage, the optimal parameters are found by a genetic algorithm, the polishing disc rotating speed, the workpiece rotating speed and the PH value parameters are controlled, the evaluation values Y2 are recalculated until the conditions are met, and one control cycle is completed.

2. The chemically enhanced, multi-parameter self-regulated liquid membrane shear polishing process under synergistic effects of claim 1, wherein: the PH adjusting module (8) comprises a liquid storage tank (801) which is used for storing acidic and alkaline agents; a liquid inlet and a liquid outlet are arranged on the liquid storage tank (801); the liquid inlet is used for adding agents; a control valve (802) and a liquid supply pump (803) are arranged at the liquid outlet.

3. The chemically enhanced, multi-parameter self-regulated liquid membrane shear polishing process under synergistic effects of claim 1, wherein: a liquid discharge port is arranged on the polishing liquid tank (3); a plug (301) is arranged in the liquid discharge port.

4. The chemically enhanced, multi-parameter self-regulated liquid membrane shear polishing process under synergistic effects of claim 3, wherein: The base (1) is provided with a waste liquid tank (101), the polishing liquid tank (3) is located in the waste liquid tank (101), and the waste liquid tank (101) is communicated with the recovery container (9) through a pipeline.

5. The chemically enhanced, multi-parameter self-regulated liquid membrane shear polishing process under synergistic effects of claim 1, wherein: The set percentage is 0.4-1%.

6. The chemically enhanced, multi-parameter self-regulated liquid membrane shear polishing process under synergistic effects of claim 2, wherein: The liquid supply pump adds 2-3ml of the adjusting reagent to the polishing liquid tank (3) each time.

7. The chemically enhanced, multi-parameter self-regulated liquid membrane shear polishing process of any of claims 1-6, wherein: The method is used for polishing processing of tungsten alloy.

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