Machining method for rotary disc of wafer conveying mechanical arm

Abstract

The invention relates to a wafer conveying mechanical arm rotary disc machining method, and relates to the technical field of precision machine manufacturing, and the method comprises the following steps: 1, adopting a 6061 aluminum alloy plate, carrying out rough machining in a CNC machining center, reserving a 0.35 mm allowance on a milling thickness single side, reserving a pressing plate position on an outer circle, and reserving a process foot in the middle of a workpiece; synchronously milling an outer circle, an inner hole and a groove characteristic single edge, and reserving the allowance of 0.35 mm; and milling a counter bore, a step and a waist groove single edge, and reserving the allowance of 0.5 mm. By optimizing the multi-process flow, the machining quality and reliability of the rotary disc are remarkably improved, a 6061 aluminum alloy plate is adopted, the dimensional precision and form and location tolerance of a workpiece in each stage are ensured through the links of rough machining, heat treatment, semi-finish machining, finish machining, aftertreatment and the like, and the machining quality of the rotary disc is improved. By reasonably reserving the machining allowance, optimizing the cutting parameters and controlling the heat treatment process, machining deformation caused by stress release and clamping errors is effectively avoided, and the size control precision and the surface quality of the pin hole are improved.

Description

Technical Field

[0001] This application relates to the field of precision machinery manufacturing technology, and in particular to a method for processing a wafer transfer robotic arm rotary table. Background Technology

[0002] As a key component, the rotary table is widely used in high-precision applications such as aerospace, precision instruments, and high-end equipment. Its machining quality directly affects the operational accuracy, stability, and service life of the equipment. The machining of rotary tables typically involves a complex multi-stage process, including roughing, heat treatment, semi-finishing, finishing, and post-processing. This requires comprehensive consideration of factors such as material properties, machining accuracy, surface quality, and machining efficiency. Taking lightweight, high-strength materials such as 6061 aluminum alloy as an example, during machining, it is necessary to ensure the dimensional accuracy and geometric tolerances of the workpiece at each stage of machining by reasonably reserving machining allowances, optimizing cutting parameters, and controlling heat treatment processes. Simultaneously, machining deformation caused by stress release, clamping errors, and other factors must be avoided.

[0003] While rotary table machining has developed into a relatively mature process system, several technical problems remain to be solved. For example, in multi-process machining, repeated clamping of the workpiece can lead to the accumulation of datum transfer errors, affecting the dimensional and positional tolerances such as coaxiality, cylindricity, and concentricity of key features like hole systems and stepped surfaces. For machining high-precision pin holes and deep holes, traditional machining processes struggle to meet increasingly stringent requirements in terms of dimensional control, surface roughness, and machining efficiency, especially when dealing with small-diameter deep holes, which can result in rapid tool wear and poor chip removal. Furthermore, residual stress may exist on the workpiece after heat treatment; if not effectively eliminated, it can cause slow deformation during subsequent finishing and use, affecting the long-term accuracy of the rotary table. Additionally, details in surface treatment processes, such as controlling the uniformity of anodized film thickness and protecting non-machined areas during polishing, can also lead to poor product consistency or localized damage. To address the shortcomings of existing technologies in areas such as machining accuracy control, stress relief, complex feature processing, and surface treatment, and to further improve the machining quality and reliability of the rotary table, we propose a rotary table machining method for a wafer transfer robotic arm. Summary of the Invention

[0004] The purpose of this application is to provide a method for machining a wafer transfer robotic arm rotary table. This technical solution solves the problems mentioned above, such as the accumulation of reference transfer errors due to multiple machining processes and clamping of the rotary table, which affects the geometric tolerances; the difficulty in meeting the requirements for dimensional control in high-precision pin hole and deep hole machining; the problem that small-diameter deep holes are prone to tool wear; the possibility of deformation caused by residual stress after heat treatment; and the problem that surface treatment details can lead to poor product consistency.

[0005] The wafer transfer robotic arm rotary table processing method provided in this application adopts the following technical solution:

[0006] A method for processing wafers using a rotary table via a robotic arm includes the following steps:

[0007] Step 1: Using 6061 aluminum alloy sheet, perform rough machining on a CNC machining center: mill the thickness with a 0.35mm allowance on each side, reserve a pressure plate position on the outer circle, and reserve a process foot in the middle of the workpiece; simultaneously mill the outer circle, inner hole, and groove features with a 0.35mm allowance on each side, and mill the countersunk hole, step, and waist groove with a 0.5mm allowance on each side.

[0008] Step 2, heat treatment: Place the workpiece in an environment of 160℃±5℃ and keep it at that temperature for 4±0.5 hours, then allow it to cool naturally to room temperature;

[0009] Step 3, semi-finishing: Mill the thickness to 0.1mm allowance on each side in a CNC machining center, and machine the features in the left view to the design dimensions; perform a medium finish on the Φ63 and Φ78.5 holes, leaving a 0.2mm allowance on each side, and machine through to 2-Φ4 pin holes and chamfer them;

[0010] Step 4, Finishing: Machining on a surface grinder with the thickness surface as the reference, ensuring thickness tolerance ±0.03mm, flatness ≤0.01mm, and roughness Ra0.8; finish milling 2-Φ40±0.04 holes, 2-Φ78.5±0.03 holes, and a 1.5±0.005 step on a CNC machining center, controlling cylindricity ≤0.008mm and concentricity ≤0.01mm; positioning and clamping with 2-Φ4±0.01 pin holes, machining Φ214 (+0.01 / +0.04) holes, 4 un-indicated tolerance grooves, and 2-Φ80 (+2±0.008) holes in the same process;

[0011] Step 5, post-processing: After tapping by the fitter, the specified Ra0.8 surface is directionally polished. During degreasing and cleaning, compressed air of 0.3-0.5MPa is used to blow out the holes and grooves. After laser marking, natural color anodizing is performed, and the oxide film thickness is 10-15μm.

[0012] Preferably, the process foot in step one is a cylinder with a diameter of Φ8±0.5mm, symmetrically distributed on the circumference of the workpiece center at 80±5mm, and its height is equal to the thickness of the workpiece; the process foot is retained before finishing the Φ214 hole in step four, and removed by wire cutting after finishing.

[0013] Preferably, the intermediate finishing process in step three adopts a layered milling strategy, with each layer having a cutting depth ≤0.2mm, a spindle speed of 8000-12000rpm, and a feed rate of 800-1200mm / min; the Φ78.5 hole is subjected to helical interpolation milling, with an interpolation angle increment ≤0.5° / tooth.

[0014] Preferably, in step four, the grinding process employs a double-end grinding technique, with a grinding wheel grit size of #180-#240, a coolant flow rate of 20-30 L / min, and a table reciprocating speed of 10-15 m / min. After machining, online compensation is performed using a coordinate measuring machine (CMM). The compensation model is as follows:

[0015]

[0016] In the formula, For compensation amount, This is the proportionality coefficient. For height deviation, The integral coefficient is... For the integral term of height deviation, This is the measured height value. To set the height value, =0.6-0.8, =0.02-0.04.

[0017] Preferably, in step four, the machining of the 2-Φ4±0.01 pin holes is carried out using a gun drilling process. The drill bit coating is TiAlN, and the cutting parameters are: rotation speed 15000-18000rpm, feed 0.03-0.05mm / rev, and internal cooling pressure 3-5MPa. After machining, the hole diameter is checked by a pneumatic gauge. If the diameter exceeds the tolerance, electrochemical micro-trimming is used. The trimming current is 10-15A, and the concentration of NaNO3 in the electrolyte is 8-12wt%.

[0018] Preferably, the directional polishing in step five uses an automatic polishing machine with a sanding belt grit size of P600-P800, a polishing pressure of 0.1-0.3MPa, and an oscillation frequency of 5-8Hz; the non-polished area is covered with a high-temperature resistant silicone film with a film thickness of 0.5-1mm.

[0019] Preferably, the anodizing is performed using a pulsed power supply with a forward current density of 1.5-2 A / dm², a duty cycle of 30%-40%, and an electrolyte temperature of 18-22℃; the post-oxidation sealing treatment uses a nickel salt solution with a nickel ion concentration of 0.8-1.2 g / L, a treatment temperature of 90-95℃, and a time of 20-30 min.

[0020] Preferably, after finishing in step four, a vibration aging treatment is added: the workpiece is placed on a multi-axis vibration platform with a frequency of 80-100Hz, an acceleration of 1.0-1.5g, a duration of 45-60min, and the vibration direction is at a 45° angle to the finishing tool path.

[0021] Preferably, the degreasing and cleaning process is performed in three stages: spraying with alkaline cleaning agent (pH 9-11) for 5-8 minutes → ultrasonic cleaning with deionized water (frequency 40kHz) for 3-5 minutes → vacuum drying (pressure -0.08~-0.1MPa, temperature 60-70℃).

[0022] Preferably, the key form and position tolerance control adopts a reference transfer chain: the grinding thickness surface is the first reference, the 2-Φ4 pin hole is the second reference, and the Φ214 hole is the third reference; the coaxiality is detected by a laser interferometer, and the measurement point collects data every 10mm along the axis, with a fitting deviation value Δ≤0.005mm.

[0023] In summary, this application includes at least one of the following beneficial technical effects:

[0024] This invention significantly improves the machining quality and reliability of the rotary table by optimizing multiple processes. Using 6061 aluminum alloy sheet, the process involves rough machining, heat treatment, semi-finishing, finishing, and post-processing to ensure dimensional accuracy and geometric tolerances at each stage. By reasonably reserving machining allowances, optimizing cutting parameters, and controlling the heat treatment process, machining deformation caused by stress release and clamping errors is effectively avoided. High-precision pin holes are machined using gun drilling, combined with electrochemical micro-trimming technology, significantly improving the dimensional control accuracy and surface quality of the pin holes. Vibration aging treatment eliminates residual stress, further enhancing the long-term accuracy of the rotary table. Pulse power anodizing ensures uniform oxide film thickness, while directional polishing effectively protects non-machined areas, improving product consistency and appearance quality. Attached Figure Description

[0025] Figure 1 This is a flowchart of the method of the present invention;

[0026] Figure 2 This is a flowchart of the degreasing and cleaning method of the present invention. Detailed Implementation

[0027] The following is in conjunction with the appendix Figure 1 -Appendix Figure 2 This application will be described in further detail below.

[0028] Example 1: A wafer transfer robotic arm rotary table processing method, referring to... Figure 1 As shown, it includes the following steps:

[0029] 6061 aluminum alloy sheet is used as the raw material. This material has good mechanical properties and machinability, making it suitable for manufacturing precision rotating parts. The entire processing flow, from rough machining to post-processing, involves multiple key steps. Each step ensures the high precision requirements of the final product through precise parameter control and process design.

[0030] The roughing process in step one is performed on a CNC machining center. A vertical machining center with high rigidity and positioning accuracy is selected, equipped with an automatic tool changer to accommodate multi-process machining requirements. First, milling is performed in the thickness direction using an end mill to remove most of the material in a layered cutting manner, leaving a 0.35mm machining allowance on each side. This allowance balances the accuracy requirements and efficiency of subsequent machining. A clamping plate position is specifically reserved for machining the outer cylindrical area. This area is designed as a 15-20mm wide annular platform for mounting an adjustable clamping plate fixture. A four-point symmetrical clamping method ensures the stability of the workpiece during high-speed cutting. Simultaneously, a process foot structure is machined in the center of the workpiece. This process foot is a cylinder with a diameter of Φ8±0.5mm, symmetrically distributed around the circumference of 80±5mm from the workpiece center. It is milled along the circumferential trajectory using an end mill, with a height equal to the workpiece thickness to provide uniform support rigidity. During the feature machining stage, the same 0.35mm single-sided allowance strategy is adopted for external diameters, internal holes, and grooves. End mills and keyway cutters with matching diameters are used, and contour cutting paths are generated through CAM software to ensure the initial forming accuracy of each feature. For complex structures such as countersunk holes, steps, and waist grooves, a 0.5mm single-sided allowance is adopted, and deep cavity structures are machined using a peck milling method to avoid tool deformation due to excessive axial load. The depth of cut per pass is controlled within 3mm, the spindle speed is set to 6000-8000rpm, and the feed rate is 600-1000mm / min to ensure that the roughing surface roughness is controlled within Ra6.3.

[0031] Step two, the heat treatment process, employs a box-type resistance furnace for artificial aging. The rough-machined workpiece is placed stably in the center of the furnace chamber, and the furnace temperature is monitored in real time using thermocouples to ensure the working area temperature is maintained at 160℃±5℃. The holding period lasts for 4±0.5 hours, a time setting based on the aging hardening curve of 6061 aluminum alloy to ensure sufficient and uniform distribution of precipitated phases. After the holding period, the furnace door is opened to allow the workpiece to cool naturally at room temperature. Strong airflow disturbances are avoided during the cooling process to prevent new stresses caused by temperature gradients. After cooling to 25℃±5℃, the workpiece is removed, and the surface hardness is tested using a hardness tester to ensure it reaches the target range of HB90-110, providing a stable material property foundation for subsequent processing.

[0032] Step three, semi-finishing, is performed on the same CNC machining center. First, a second milling is carried out in the thickness direction, using a high-precision flat-jaw vise for clamping. The rough-machined bottom surface is used as a reference, and the flatness is calibrated with a dial indicator to ensure a clamping deviation ≤0.02mm. A sharp high-speed steel end mill is used to remove the remaining material with a single depth of cut of 0.15mm, ultimately retaining a 0.1mm machining allowance on each side. This allowance is designed to provide a reasonable amount of material removal for subsequent grinding processes. Before machining the features in the left-side view, the actual coordinates of the workpiece are collected using a coordinate measuring machine to correct coordinate system deviations and ensure that the positional accuracy of each feature meets design requirements. For the finishing of the Φ63 and Φ78.5 holes, a layered milling strategy is adopted, with the depth of cut for each layer strictly controlled to ≤0.2mm. The spindle speed is increased to 8000-12000rpm to achieve high-speed cutting, and the feed rate is 800-1200mm / min to balance surface quality and efficiency. The Φ78.5 hole is machined using helical interpolation milling. The helical interpolation trajectory is generated by a CNC system, with an interpolation angle increment ≤0.5° / tooth, ensuring the machining trajectory density on the hole wall and reducing step-like residue. The 2-Φ4 pin holes are machined using gun drilling, employing a precision gun drill with a TiAlN coating. This coating has high hardness and wear resistance, making it suitable for deep hole machining. Cutting parameters are set at a speed of 15000-18000 rpm and a feed rate of 0.03-0.05 mm / rev. The internal cooling system provides 3-5 MPa high-pressure coolant to effectively cool the tool and remove chips. After processing, the aperture is measured using a pneumatic measuring instrument. This instrument utilizes the correlation between airflow and aperture size, achieving a measurement accuracy of ±0.005mm. If deviations occur, an electrochemical micro-adjustment process is employed, using an electrolyte with a NaNO3 concentration of 8-12wt% and applying an adjustment current of 10-15A. The aperture is then slightly corrected through the anodic dissolution principle to ensure that the final size is within the range of Φ4±0.01mm.

[0033] Step four, the finishing process, is divided into two stages: surface grinding and precision milling. First, precision machining in the thickness direction is performed on a double-end surface grinder using resin-based grinding wheels with a grit size of #180-#240. These wheels have moderate hardness and are suitable for precision grinding of aluminum alloys. Water-based grinding fluid is used as the coolant, with a flow rate controlled at 20-30 L / min to ensure adequate cooling and lubrication of the grinding area. The table reciprocating speed is set to 10-15 m / min, and the movement speed is precisely controlled by a variable frequency motor to avoid surface chatter caused by speed fluctuations. During the grinding process, a coordinate measuring machine is used to detect the thickness dimension online and collect the measured height value Hm in real time. After comparing it with the set height value Hd, the compensation amount is calculated through the compensation model ΔH=Kp×(Hm-Hd)+Ki×∫(Hm-Hd)dt, where the proportional coefficient Kp is 0.6-0.8 and the integral coefficient Ki is 0.02-0.04. The grinding wheel feed is automatically adjusted by the CNC system to ensure that the final thickness tolerance is ±0.03mm, the flatness is ≤0.01mm, and the roughness Ra0.8.

[0034] When precision milling holes and steps in a CNC machining center, 2-Φ4±0.01 pin holes are used as positioning datums. High-precision clamping is achieved through interference fit (fit clearance ≤0.005mm) between precision positioning pins and workpiece pin holes. First, 2-Φ40±0.04 holes and 2-Φ78.5±0.03 holes are precision milled using carbide precision boring tools, employing boring rather than milling to improve the roundness and cylindricity of the holes. During boring, the spindle speed is controlled at 5000-6000rpm, and the feed rate is 100-150mm / min. Multiple micro-feeds (0.05mm each) are used to correct the hole size and shape, ensuring cylindricity ≤0.008mm. For the 1.5±0.005 step, an end mill is used with a vertical feed. The step height is measured in real-time using a depth micrometer, and checked after each machining operation until the dimensional requirements are met. When machining Φ214 (+0.01 / +0.04) holes in the same process, the process foot in the middle of the workpiece is first removed. A wire EDM machine is then used to precisely cut along the root of the process foot, with the cutting speed controlled below 10 mm² / min to avoid cutting stress affecting workpiece accuracy. After cutting, the hole is positioned using a pin hole, and the hole wall is rough-milled using a large-diameter end mill. Finally, a precision boring tool is used for machining to ensure the dimensional accuracy and surface roughness of the hole. The machining of the four un-toleranced grooves uses high-speed milling with a small-diameter end mill at a speed of 10000-12000 rpm and a feed rate of 1500-2000 mm / min. A smooth cutting path is generated using CAM software to ensure the positional accuracy and surface quality of the grooves. The machining of the two Φ80 (+2±0.008) holes also uses boring technology, with a high-precision boring head. Precision machining is achieved by finely adjusting the boring tool size. The hole diameter is continuously monitored during machining to ensure that the dimensions are within the tolerance range.

[0035] The newly added vibration aging treatment in step four utilizes a multi-axis vibration platform. The finished workpiece is fixed to the center of the platform using a flexible fixture, which allows the workpiece to respond freely in the vibration direction. Vibration parameters are set as follows: frequency 80-100Hz, covering the workpiece's first natural frequency; acceleration 1.0-1.5g; duration 45-60 minutes. The vibration direction is precisely adjusted by the platform control system to ensure a 45° angle with the finishing tool path, effectively eliminating residual stress in all directions. During aging, the vibration amplitude is monitored using an accelerometer to ensure uniform vibration in all directions. After treatment, residual surface stress is measured using a stress meter, ensuring a reduction of over 60%.

[0036] Step five, the post-processing steps, begins with tapping by a fitter. For holes requiring threaded connections, a combination of manual and machine tapping is used. For threads with a diameter ≤ M6, manual tapping is used to ensure perpendicularity, while threads with a diameter ≥ M8 are machine tapped. A torque overload protection device is provided to prevent tap breakage. Before tapping, the pilot hole size is checked to ensure it meets thread processing standards. During the tapping process, special cutting fluid is applied to reduce tool wear.

[0037] Directional polishing is performed on a designated Ra0.8 surface using an automatic polishing machine with a belt grit of P600-P800. This belt grit effectively removes grinding marks and creates a smooth surface. The polishing head pressure is set to 0.1-0.3 MPa and precisely adjusted via a pneumatic control system, with an oscillation frequency of 5-8 Hz to ensure the polishing path evenly covers the entire machined surface. A 0.5-1 mm thick high-temperature resistant silicone film is pre-attached to non-polished areas. This film is fixed by electrostatic adsorption or low-residue adhesive, and the edges are trimmed with precision blades to ensure clear boundaries of the protected area. During polishing, the integrity of the film layer is checked periodically to prevent polishing fluid from seeping into non-machined areas.

[0038] Example 2: Degreasing and cleaning are performed in three stages, as per [reference needed]. Figure 2 As shown, the process includes the following steps: The first stage involves spraying with an alkaline cleaning agent (pH 9-11), a solution of sodium hydroxide and a surfactant. The temperature is controlled at 50-60℃, the spray pressure at 0.2-0.3MPa, and the treatment lasts for 5-8 minutes, effectively removing oil and cutting fluid residue from the workpiece surface. The second stage involves ultrasonic cleaning with deionized water using a 40kHz ultrasonic cleaner for 3-5 minutes. This utilizes cavitation to remove impurities from micro-pores and grooves. During the cleaning process, deionized water is circulated and filtered to ensure a water conductivity ≤10μS / cm. The third stage involves vacuum drying. The workpiece is placed in a vacuum drying oven, with the pressure maintained at -0.08~-0.1MPa and the temperature at 60-70℃ for 30-45 minutes. By lowering the air pressure, the boiling point of water is reduced, ensuring complete evaporation of moisture from deep and blind holes, preventing residual water stains from affecting subsequent processes.

[0039] The laser marking process uses a fiber laser marking machine with a wavelength of 1064 nm, a power of 20 - 30 W, and a marking speed of 500 - 1000 mm / s. According to the design requirements, the product number and batch information are engraved at the specified position, and the marking depth is controlled within 0.05 - 0.1 mm to ensure clear字迹 and no impact on the surface performance of the workpiece.

[0040] The anodic oxidation treatment uses a pulsed power supply with a forward current density of 1.5 - 2 A / dm² and a duty cycle of 30% - 40%. This power supply parameter setting can effectively improve the density and uniformity of the oxide film. The electrolyte is a sulfuric acid solution, and the temperature is strictly controlled at 18 - 22 °C, and the temperature is maintained stable through the circulation cooling of a chiller. The oxidation process lasts for 40 - 60 min, and the voltage and current changes are monitored in real time to ensure uniform growth of the film thickness. After oxidation, a sealing treatment is carried out using a nickel salt solution (nickel ion concentration 0.8 - 1.2 g / L), the treatment temperature is 90 - 95 °C, and the time is 20 - 30 min. The pores of the oxide film are filled through a thermal sealing reaction to improve corrosion resistance and insulation. After sealing, the surface is rinsed with deionized water, and the film thickness is detected after drying to ensure that the technical requirement of 10 - 15 μm is met.

[0041] The control of key geometric tolerances in the entire processing process is based on a reference transfer chain system. The ground thickness surface is used as the first reference, and this reference surface achieves high-precision flatness through double-sided grinding and serves as the basis for all subsequent processing and inspection. The second reference is 2 - Φ4 pin holes, and their size and position accuracy are ensured through gun drilling and electrochemical dressing, serving as the main reference for workpiece positioning. The third reference is the Φ214 hole, and its coaxiality requirement with the first two references is achieved through precision boring and reference conversion. Coaxiality detection uses a laser interferometer. The instrument is placed in a constant temperature inspection room (temperature 20 ± 1 °C), the被测 workpiece is fixed on a high-precision rotating platform, the laser beam scans along the hole axis direction, a set of data is collected every 10 mm, and the axis deviation is fitted through a special software to ensure that the fitted deviation value Δ ≤ 0.005 mm. During the detection process, the environmental vibration is monitored, and a vibration isolation platform is used to isolate external interference to ensure the reliability of the measurement data.

[0042] During the connection process of each process, anti-static turnover boxes are used to transport the workpieces to avoid bumps and contamination. Before each batch of processing, first-piece inspection is carried out, and the key dimensions and geometric tolerances are detected through a coordinate measuring machine. Only after confirmation of compliance can mass production be carried out. During the processing, the CNC program is subjected to multiple verifications, and the cutting path is simulated through simulation software to avoid tool interference and over-cutting phenomena. For key processes such as heat treatment, grinding, and anodic oxidation, a real-time data recording system is established to store parameters such as temperature, pressure, and time to achieve full-process traceability.

[0043] Through the detailed process design and parameter control described above, from material selection to the precise operation of each processing stage, and then to the surface treatment and inspection in the post-processing, the entire rotary table processing process forms a complete high-precision manufacturing system, ensuring that the final product meets the strict requirements for dimensional tolerances, geometrical accuracy and surface quality, and is suitable for core component applications in the field of high-precision mechanical transmission.

[0044] In summary, the advantages of this invention are:

[0045] The rotary table machining method described in this invention, through systematic process innovation and precision control strategies, constructs a complete precision manufacturing system from material processing to surface treatment, demonstrating significant advantages in ensuring machining accuracy, improving product performance, and optimizing production efficiency. Firstly, the design and application of the process foot structure provides stable rigid support for roughing and semi-finishing. Its cylindrical shape, symmetrically distributed around the workpiece's central circumference, effectively balances cutting forces during machining, preventing workpiece deformation due to clamping stress or cutting vibration. Furthermore, precise removal via wire cutting ensures that the finishing stage is unaffected by residual structures, laying the geometric foundation for subsequent high-precision machining. The construction of the datum transfer chain system achieves hierarchical control of geometric tolerances. A planar positioning datum is established using the ground thickness surface as the first datum; axial positioning is achieved through a high-precision pin hole forming a second datum; and coaxiality transfer is completed using the center hole as the third datum. This multi-datum collaborative control strategy, combined with the precision detection of a laser interferometer, controls key geometric tolerances to micron-level accuracy, meeting the stringent assembly requirements of precision mechanical components.

[0046] The innovative introduction of vibration aging treatment effectively solves the problem of residual stress release after finishing. By controlling specific frequency, acceleration, and vibration direction, the internal stress field of the workpiece is homogenized. Compared with traditional aging processes, this method specifically eliminates residual stress related to the machining path, improving the dimensional stability of the workpiece during long-term use, and is especially suitable for stress-sensitive materials such as aluminum alloys. The directional polishing and pulse anodizing processes in the surface treatment stage are synergistically optimized. The former, through belt parameter control and non-machined area protection technology, ensures the specified surface roughness while preventing contamination of other areas. The latter utilizes pulse power technology to improve the density and uniformity of the oxide film, combined with nickel salt sealing treatment, achieving high industrial standards for oxide film thickness and corrosion resistance, balancing functionality and durability.

[0047] In terms of process control, the application of strategies such as layered milling and helical interpolation milling, combined with online detection and compensation models, enables precise allocation of allowances and dynamic error correction from roughing to finishing, ensuring the accuracy transfer of each feature dimension in multi-process machining. The segmented degreasing and cleaning process, through a combination of alkaline spraying, ultrasonic cleaning, and vacuum drying, thoroughly removes residual impurities from the holes and grooves, preventing contaminants from affecting subsequent processes such as anodizing and improving surface treatment consistency. Overall, this machining method, through the organic connection of process steps, quantitative control of key parameters, and integrated application of detection technologies, forms a manufacturing system that combines precision assurance, efficiency optimization, and quality stability. It is suitable for the mass production of high-precision rotary parts and has significant practical implications for promoting process upgrades in the field of precision machining.

[0048] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. A method for processing wafers using a rotary table with a robotic arm, characterized in that, Includes the following steps: Step 1: Using 6061 aluminum alloy sheet, perform rough machining on a CNC machining center: mill the thickness with a 0.35mm allowance on each side, reserve a pressure plate position on the outer circle, and reserve a process foot in the middle of the workpiece; simultaneously mill the outer circle, inner hole, and groove features with a 0.35mm allowance on each side, and mill the countersunk hole, step, and waist groove with a 0.5mm allowance on each side. Step 2, heat treatment: Place the workpiece in an environment of 160℃±5℃ and keep it at that temperature for 4±0.5 hours, then allow it to cool naturally to room temperature; Step 3, semi-finishing: Mill the thickness to 0.1mm allowance on each side in a CNC machining center, and machine the features in the left view to the design dimensions; perform a medium finish on the Φ63 and Φ78.5 holes, leaving a 0.2mm allowance on each side, and machine through to 2-Φ4 pin holes and chamfer them; Step 4, Finishing: Machining on a surface grinder with the thickness surface as the reference, ensuring thickness tolerance ±0.03mm, flatness ≤0.01mm, and roughness Ra0.8; finish milling 2-Φ40±0.04 holes, 2-Φ78.5±0.03 holes, and a 1.5±0.005 step on a CNC machining center, controlling cylindricity ≤0.008mm and concentricity ≤0.01mm; positioning and clamping with 2-Φ4±0.01 pin holes, machining Φ214 (+0.01 / +0.04) holes, 4 un-indicated tolerance grooves, and 2-Φ80 (+2±0.008) holes in the same process; Step 5, post-processing: After tapping by the fitter, the specified Ra0.8 surface is directionally polished. During degreasing and cleaning, compressed air of 0.3-0.5MPa is used to blow out the holes and grooves. After laser marking, natural color anodizing is performed, and the oxide film thickness is 10-15μm.

2. The wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, The process feet mentioned in step one are cylinders with a diameter of Φ8±0.5mm, symmetrically distributed on the circumference of the workpiece center at 80±5mm, with a height equal to the thickness of the workpiece; the process feet are retained before finishing the Φ214 hole in step four, and removed by wire cutting after finishing.

3. The wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, In step three, the intermediate finishing process adopts a layered milling strategy, with each layer having a cutting depth of ≤0.2mm, a spindle speed of 8000-12000rpm, and a feed rate of 800-1200mm / min; the Φ78.5 hole is subjected to helical interpolation milling, with an interpolation angle increment of ≤0.5° / tooth.

4. The wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, In step four, the grinding machine uses a double-end grinding process with a grinding wheel grit size of #180-#240, a coolant flow rate of 20-30 L / min, and a table reciprocating speed of 10-15 m / min. After machining, online compensation is performed using a coordinate measuring machine. The compensation model is as follows:    In the formula, For compensation amount, This is the proportionality coefficient. For height deviation, The integral coefficient is... For the integral term of height deviation, This is the measured height value. To set the height value, =0.6-0.8, =0.02-0.

04.

5. The wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, In step four, the 2-Φ4±0.01 pin hole is machined using a gun drill with a TiAlN coating. The cutting parameters are: rotation speed 15000-18000 rpm, feed 0.03-0.05 mm / rev, and internal cooling pressure 3-5 MPa. After machining, the hole diameter is checked by a pneumatic gauge. If the diameter exceeds the tolerance, electrochemical micro-compensation is used with a compensating current of 10-15 A and an electrolyte NaNO3 concentration of 8-12 wt%.

6. The wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, Step 5 describes directional polishing using an automatic polishing machine with a belt grit size of P600-P800, a polishing pressure of 0.1-0.3MPa, and an oscillation frequency of 5-8Hz; the non-polished areas are covered with a high-temperature resistant silicone film with a film thickness of 0.5-1mm.

7. A wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, Anodizing is performed using a pulsed power supply with a forward current density of 1.5-2 A / dm², a duty cycle of 30%-40%, and an electrolyte temperature of 18-22℃. Post-oxidation sealing is performed using a nickel salt solution with a nickel ion concentration of 0.8-1.2 g / L, a treatment temperature of 90-95℃, and a treatment time of 20-30 min.

8. A wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, After finishing in step four, add vibration aging treatment: place the workpiece on a multi-axis vibration platform with a frequency of 80-100Hz, an acceleration of 1.0-1.5g, a duration of 45-60min, and the vibration direction is at a 45° angle to the finishing tool path.

9. A wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, The degreasing and cleaning process is performed in three stages: spraying with alkaline cleaning agent (pH 9-11) for 5-8 minutes → ultrasonic cleaning with deionized water (frequency 40kHz) for 3-5 minutes → vacuum drying (pressure -0.08~-0.1MPa, temperature 60-70℃).

10. A wafer transfer robotic arm rotary table processing method according to claim 1, characterized in that, Key form and position tolerance control adopts a reference transfer chain: the grinding thickness surface is the first reference, the 2-Φ4 pin hole is the second reference, and the Φ214 hole is the third reference; coaxiality detection is carried out using a laser interferometer, and data is collected every 10mm along the axis at the measurement point, with a fitting deviation value Δ≤0.005mm.

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