Method and equipment for corroding crystal grains of single-crystal high-temperature alloy casting
Through multi-step processing methods and equipment, the problem of poor grain corrosion effect of single crystal high-temperature alloy castings is solved, and clearer grain boundary observation and efficient detection are achieved.
Patent Information
- Application Number
- CN202510754283.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-06
- Publication Date
- 2025-07-11
AI Technical Summary
The existing single crystal high-temperature alloy casting grain corrosion methods have poor corrosion effects, which leads to difficult to distinguish grain boundaries, and corrosion products are attached to the surface of the workpiece after electrochemical corrosion, affecting the observation clarity.
Multi-step treatment methods are adopted, including chemical corrosion, electrochemical corrosion, ash removal and neutralization treatment, combined with ultrasonic cleaning and drying, the corrosion process is controlled using specific solutions and parameters, and workpiece processing is performed using multiple processing tanks in the equipment.
It improves the uniformity of the surface potential distribution of the workpiece, optimizes the electrochemical corrosion effect, removes corrosion products, improves grain boundary recognition and detection accuracy and efficiency, and enhances the reproducibility and quality of detection.
Smart Images
Figure CN120293640A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of quality inspection, and particularly to a method and device for grain corrosion of single crystal superalloy castings. Background Art
[0002] Nickel-based single crystal superalloys are industrial alloys with excellent high-temperature properties and are the main materials for manufacturing advanced aeroengine and gas turbine blades. The grain boundary structure and defect distribution of nickel-based single crystal superalloys directly affect the service life of workpieces. In order to detect the grain boundary structure and defects of nickel-based single crystal superalloys, it is necessary to corrode the workpieces.
[0003] The existing methods for grain corrosion of single crystal superalloys have poor corrosion effects, resulting in difficult-to-distinguish grain boundaries; and after electrochemical corrosion, corrosion products adhere to the surface of the workpieces, resulting in unclear grain boundaries of the grains on the surface of the workpieces, which is not conducive to observation.
[0004] Based on the above technical problems, the present application proposes a method and device for grain corrosion of single crystal superalloy castings. Summary of the Invention
[0005] The purpose of the present invention is to provide a method and device for grain corrosion of single crystal superalloy castings to solve the technical problems mentioned in the background art. The purpose of the present invention is achieved through the following technical solutions: A method for grain corrosion of single crystal superalloy castings includes the following steps: Step S1: Chemically corrode the single crystal superalloy casting after sandblasting treatment; Step S2: Electrochemically corrode the single crystal superalloy casting after chemical corrosion treatment; Step S3: Remove ash from the single crystal superalloy casting after electrochemical corrosion treatment; Step S4: Neutralize the single crystal superalloy casting after ash removal treatment; Step S5: Ultrasonically clean and dry the single crystal superalloy casting after neutralization treatment.
[0006] Further, after chemical corrosion treatment and electrochemical corrosion treatment, the single crystal superalloy casting is rinsed, flushed, and dried in sequence; after ash removal treatment, neutralization treatment, and ultrasonic cleaning, the single crystal superalloy casting is rinsed.
[0007] Further, the chemical corrosion treatment process is as follows: Immerse the single-crystal superalloy casting after sandblasting treatment into the chemical corrosion solution, and treat it at a temperature of 30 - 50°C for 5 - 20 minutes; wherein, the chemical corrosion solution is a mixed solution of ferric chloride and hydrochloric acid, the content of the ferric chloride is 300 g / L - 500 g / L, and the content of the hydrochloric acid is 30 g / L - 150 g / L.
[0008] Further, the electrochemical corrosion treatment process is as follows: Immerse the single-crystal superalloy casting after chemical corrosion treatment into the electrochemical corrosion solution, and treat it at a temperature of 20 - 50°C for 3 - 20 minutes, and the electrochemical corrosion parameters are a voltage of 3 - 5 V or a current density of 0.2 - 1 mA / mm2; Wherein, the electrochemical corrosion solution is a mixed solution of sulfuric acid and phosphoric acid, and the ratio of sulfuric acid to phosphoric acid is 1:3 - 1:5; Or the electrochemical corrosion solution is a mixed solution of glacial acetic acid, ethylene glycol, phosphoric acid and deionized water. By volume, glacial acetic acid is 10% - 20%, ethylene glycol is 10% - 20%, phosphoric acid is 40% - 60%, and the balance is deionized water.
[0009] Further, the ash removal treatment process is as follows: Immerse the single-crystal superalloy casting after electrochemical corrosion treatment into the ash removal solution, wherein, the ash removal solution is a sodium hydroxide solution, the content of sodium hydroxide is 44 - 55 g / L, the ash removal temperature is 60 - 80°C at this time, and the ash removal time is 15 - 25 minutes; Or the ash removal solution is a sodium gluconate solution, the content of sodium gluconate is 44 - 55 g / L, the ash removal temperature is 60 - 80°C at this time, and the ash removal time is 15 - 25 minutes; Or the ash removal solution is a nitric acid solution, the content of the nitric acid is 400 - 600 g / L, the ash removal temperature is at room temperature at this time, and the ash removal time is 25 - 35 s.
[0010] Further, the neutralization treatment process is as follows: Immerse the single-crystal superalloy casting after ash removal treatment into the neutralization solution, and treat it at room temperature for 1 - 2 minutes; wherein, the neutralization solution is a sodium carbonate solution, and the content of sodium carbonate is 30 - 60 g / L.
[0011] Further, the temperature of rinsing is 30 - 50°C, and the time of rinsing is 0.5 - 2 minutes.
[0012] An apparatus for implementing any of the above single-crystal superalloy casting grain corrosion methods, comprising a chemical corrosion tank, an electrochemical corrosion tank, an ash removal tank, a neutralization tank, an ultrasonic cleaning tank, and a drying tank arranged in sequence. A first cleaning tank is respectively arranged between the chemical corrosion tank and the electrochemical corrosion tank, and between the electrochemical corrosion tank and the ash removal tank; a second cleaning tank is respectively arranged between the ash removal tank and the neutralization tank, between the neutralization tank and the ultrasonic cleaning tank, and between the ultrasonic cleaning tank and the drying tank.
[0013] Furthermore, the chemical corrosion tank, the electrochemical corrosion tank, the ash removal tank, and the ultrasonic cleaning tank are all provided with heating mechanisms; an air gun and a water gun are arranged in the first cleaning tank; the second cleaning tank, the ash removal tank, the neutralization tank, and the ultrasonic cleaning tank are all provided with bubbling mechanisms; the chemical corrosion tank, the electrochemical corrosion tank, and the first cleaning tank are all connected to an exhaust mechanism through pipelines; electrodes are arranged in the electrochemical corrosion tank.
[0014] Furthermore, a first chemical corrosion barrel, a second chemical corrosion barrel, and a first rinsing barrel are arranged in the chemical corrosion tank; a first electrochemical corrosion barrel, a second electrochemical corrosion barrel, and a second rinsing barrel are arranged in the electrochemical corrosion tank.
[0015] The technical solutions provided by the embodiments of the present application have at least the following technical effects or advantages: 1. By performing pretreatment on the single-crystal superalloy casting through chemical corrosion, the uniformity of the surface potential distribution of the workpiece can be improved, the surface state of the workpiece can be optimized, the corrosion effect of electrochemical corrosion can be improved, and the recognition rate of grain boundaries can be increased; 2. By performing ash removal treatment, the corrosion products adhering to the surface of the workpiece after electrochemical corrosion can be removed, which is convenient for observing the grain boundaries of the grains and improving the accuracy and efficiency of inspection; 3. By processing the single-crystal superalloy casting with an apparatus having multiple treatment tanks, the compatibility with complex workpieces can be improved, the concentration gradient of the corrosion liquid caused by manual operation can be avoided, and the reproducibility of detection can be increased; 4. By controlling the electrochemical corrosion through the potentiostatic method, the uniformity of electrochemical corrosion can be improved, unnecessary side reactions can be avoided, and the quality of the workpiece can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments recorded in the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.
[0017] Figure 1 It is a schematic structural diagram of the apparatus in the embodiment of the present application.
[0018] Reference numerals: 1, chemical etching tank; 11, first chemical etching barrel; 12, second chemical etching barrel; 13, first rinsing barrel; 2, electrochemical etching tank; 21, first electrochemical etching barrel; 22, second electrochemical etching barrel; 23, second rinsing barrel; 3, ash removal tank; 4, neutralization tank; 5, ultrasonic cleaning tank; 6, drying tank; 7, first cleaning tank; 8, second cleaning tank. Detailed implementation manners
[0019] To further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following combines the drawings and preferred embodiments to detail the specific implementation manners, structures, features and their effects of the present invention as follows.
[0020] Embodiment 1 A method for grain etching of single crystal superalloy castings includes the following steps: Step S1: Perform chemical etching treatment on the single crystal superalloy casting after sandblasting treatment; The chemical etching treatment process is: Immerse the single crystal superalloy casting after sandblasting treatment in the chemical etching solution and treat it at a temperature of 30 - 50 °C for 5 - 20 min. Among them, the chemical etching solution is a mixed solution of ferric chloride and hydrochloric acid, the content of ferric chloride is 300 g / L - 500 g / L, and the content of hydrochloric acid is 30 g / L - 150 g / L.
[0021] Step S11: Rinse the single crystal superalloy casting after chemical etching treatment with tap water, the rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0022] Step S2: Perform electrochemical etching treatment on the single crystal superalloy casting after chemical etching treatment; The electrochemical etching treatment process is: Immerse the single crystal superalloy casting after chemical etching treatment in the electrochemical etching solution and treat it at a temperature of 20 - 50 °C for 3 - 20 min, and the electrochemical etching parameters are a voltage of 3 - 5 V or a current density of 0.2 - 1 mA / mm2; Among them, the electrochemical etching solution is a mixed solution of sulfuric acid and phosphoric acid, and the ratio of sulfuric acid to phosphoric acid is 1:3 - 1:5.
[0023] Step S21: Rinse the single crystal superalloy casting after electrochemical etching treatment with tap water, the rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0024] Step S3: Perform ash removal on the single-crystal superalloy casting after electrochemical corrosion treatment; The ash removal treatment process is as follows: Immerse the single-crystal superalloy casting after electrochemical corrosion treatment in the ash removal solution. Here, the ash removal solution is a sodium hydroxide solution, the content of sodium hydroxide is 44 - 55 g / L, the ash removal temperature is 60 - 80 °C, and the ash removal time is 15 - 25 min.
[0025] Step S31: Rinse the single-crystal superalloy casting after ash removal treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0026] Step S4: Perform neutralization treatment on the single-crystal superalloy casting after ash removal treatment; The neutralization treatment process is as follows: Immerse the single-crystal superalloy casting after ash removal treatment in the neutralization solution and treat it at room temperature for 1 - 2 min. Here, the neutralization solution is a sodium carbonate solution, and the content of sodium carbonate is 30 - 60 g / L.
[0027] Step S41: Rinse the single-crystal superalloy casting after neutralization treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0028] Step S5: Perform ultrasonic cleaning and drying on the single-crystal superalloy casting after neutralization treatment.
[0029] Among them, the frequency of the ultrasonic wave is 40 - 100 kHz, the power density of the ultrasonic wave is 0.3 - 0.5 W / cm², the cleaning temperature is 40 - 80 °C, the cleaning time is 3 - 10 minutes, and the drying temperature is 80 - 100 °C.
[0030] Before drying, step S51 is also performed: Rinse the single-crystal superalloy casting after ultrasonic cleaning with deionized water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0031] Example 2 A method for grain corrosion of single-crystal superalloy castings includes the following steps: Step S1: Perform chemical corrosion treatment on the single-crystal superalloy casting after sandblasting treatment; The chemical corrosion treatment process is as follows: Immerse the single-crystal superalloy casting after sandblasting treatment in the chemical corrosion solution and treat it at a temperature of 30 - 50 °C for 5 - 20 min. Here, the chemical corrosion solution is a mixed solution of ferric chloride and hydrochloric acid, the content of ferric chloride is 300 g / L - 500 g / L, and the content of hydrochloric acid is 30 g / L - 150 g / L.
[0032] Step S11: Rinse the single-crystal superalloy casting after chemical corrosion treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0033] Step S2: Conduct electrochemical corrosion treatment on the single-crystal superalloy casting after chemical corrosion treatment; The electrochemical corrosion treatment process is as follows: Immerse the single-crystal superalloy casting after chemical corrosion treatment in the electrochemical corrosion solution and treat it at a temperature of 20 - 50 °C for 3 - 20 min. The electrochemical corrosion parameters are a voltage of 3 - 5 V or a current density of 0.2 - 1 mA / mm2; Among them, the electrochemical corrosion solution is a mixed solution of glacial acetic acid, ethylene glycol, phosphoric acid, and deionized water. By volume, glacial acetic acid is 10% - 20%, ethylene glycol is 10% - 20%, phosphoric acid is 40% - 60%, and the balance is deionized water.
[0034] Step S21: Rinse the single-crystal superalloy casting after electrochemical corrosion treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0035] Step S3: Conduct ash removal treatment on the single-crystal superalloy casting after electrochemical corrosion treatment; The ash removal treatment process is as follows: Immerse the single-crystal superalloy casting after electrochemical corrosion treatment in the ash removal solution. Among them, the ash removal solution is a sodium hydroxide solution, the content of sodium hydroxide is 44 - 55 g / L, the ash removal temperature is 60 - 80 °C, and the ash removal time is 15 - 25 min.
[0036] Step S31: Rinse the single-crystal superalloy casting after ash removal treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0037] Step S4: Conduct neutralization treatment on the single-crystal superalloy casting after ash removal treatment; The neutralization treatment process is as follows: Immerse the single-crystal superalloy casting after ash removal treatment in the neutralization solution and treat it at room temperature for 1 - 2 min; Among them, the neutralization solution is a sodium carbonate solution, and the content of sodium carbonate is 30 - 60 g / L.
[0038] Step S41: Rinse the single-crystal superalloy casting after neutralization treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0039] Step S5: Conduct ultrasonic cleaning and drying on the single-crystal superalloy casting after neutralization treatment.
[0040] Among them, the frequency of the ultrasonic wave is 40 - 100 kHz, the power density of the ultrasonic wave is 0.3 - 0.5 W / cm², the cleaning temperature is 40 - 80 °C, the cleaning time is 3 - 10 minutes, and the drying temperature is 80 - 100 °C.
[0041] Before drying, step S51 is also performed: rinsing the single-crystal superalloy casting after ultrasonic cleaning with deionized water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0042] Example 3 A method for grain corrosion of single-crystal superalloy castings includes the following steps: Step S1: Chemically corrode the single-crystal superalloy casting after sandblasting treatment; The chemical corrosion treatment process is as follows: Immerse the single-crystal superalloy casting after sandblasting treatment in the chemical corrosion solution and treat it at a temperature of 30 - 50 °C for 5 - 20 min. Among them, the chemical corrosion solution is a mixed solution of ferric chloride and hydrochloric acid. The content of ferric chloride is 300 g / L - 500 g / L, and the content of hydrochloric acid is 30 g / L - 150 g / L.
[0043] Step S11: Rinse the single-crystal superalloy casting after chemical corrosion treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0044] Step S2: Electrochemically corrode the single-crystal superalloy casting after chemical corrosion treatment; The electrochemical corrosion treatment process is as follows: Immerse the single-crystal superalloy casting after chemical corrosion treatment in the electrochemical corrosion solution and treat it at a temperature of 20 - 50 °C for 3 - 20 min. The electrochemical corrosion parameters are a voltage of 3 - 5 V or a current density of 0.2 - 1 mA / mm²; Among them, the electrochemical corrosion solution is a mixed solution of glacial acetic acid, ethylene glycol, phosphoric acid, and deionized water. By volume, glacial acetic acid is 10% - 20%, ethylene glycol is 10% - 20%, phosphoric acid is 40% - 60%, and the balance is deionized water.
[0045] Step S21: Rinse the single-crystal superalloy casting after electrochemical corrosion treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0046] Step S3: Remove ash from the single-crystal superalloy casting after electrochemical corrosion treatment; The ash removal treatment process is as follows: Immerse the single-crystal superalloy casting after electrochemical corrosion treatment in the ash removal solution. Among them, the ash removal solution is a sodium gluconate solution, and the content of sodium gluconate is 44 - 55 g / L. At this time, the ash removal temperature is 60 - 80 °C, and the ash removal time is 15 - 25 min.
[0047] Step S31: Rinse the single-crystal superalloy casting after ash removal treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0048] Step S4: Perform neutralization treatment on the single-crystal superalloy casting after ash removal treatment; The neutralization treatment process is as follows: Immerse the single-crystal superalloy casting after ash removal treatment in the neutralization solution and treat it at room temperature for 1 - 2 min; among them, the neutralization solution is a sodium carbonate solution, and the content of sodium carbonate is 30 - 60 g / L.
[0049] Step S41: Rinse the single-crystal superalloy casting after neutralization treatment with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0050] Step S5: Perform ultrasonic cleaning and drying on the single-crystal superalloy casting after neutralization treatment.
[0051] Among them, the frequency of the ultrasonic wave is 40 - 100 kHz, the power density of the ultrasonic wave is 0.3 - 0.5 W / cm², the cleaning temperature is 40 - 80 °C, the cleaning time is 3 - 10 minutes, and the drying temperature is 80 - 100 °C.
[0052] Before drying, step S51 is also performed: Rinse the single-crystal superalloy casting after ultrasonic cleaning with deionized water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0053] Example 4 A method for grain corrosion of single-crystal superalloy castings includes the following steps: Step S1: Perform chemical corrosion treatment on the single-crystal superalloy casting after sandblasting treatment; The chemical corrosion treatment process is as follows: Immerse the single-crystal superalloy casting after sandblasting treatment in the chemical corrosion solution and treat it at a temperature of 30 - 50 °C for 5 - 20 min. Among them, the chemical corrosion solution is a mixed solution of ferric chloride and hydrochloric acid, the content of ferric chloride is 300 g / L - 500 g / L, and the content of hydrochloric acid is 30 g / L - 150 g / L.
[0054] Step S11: Rinse the single-crystal superalloy casting after chemical etching with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0055] Step S2: Perform electrochemical etching on the single-crystal superalloy casting after chemical etching; The electrochemical etching process is as follows: Immerse the single-crystal superalloy casting after chemical etching in the electrochemical etching solution and process it at a temperature of 20 - 50 °C for 3 - 20 min. The electrochemical etching parameters are a voltage of 3 - 5 V or a current density of 0.2 - 1 mA / mm2; Among them, the electrochemical etching solution is a mixed solution of glacial acetic acid, ethylene glycol, phosphoric acid, and deionized water. By volume, glacial acetic acid is 10% - 20%, ethylene glycol is 10% - 20%, phosphoric acid is 40% - 60%, and the balance is deionized water.
[0056] Step S21: Rinse the single-crystal superalloy casting after electrochemical etching with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min. After rinsing, rinse with high-pressure tap water at 20 bar for 1 min and then dry with a high-pressure air gun.
[0057] Step S3: Perform ash removal on the single-crystal superalloy casting after electrochemical etching; The ash removal process is as follows: Immerse the single-crystal superalloy casting after electrochemical etching in the ash removal solution. Among them, the ash removal solution is a nitric acid solution, and the content of nitric acid is 400 - 600 g / L. At this time, the ash removal temperature is room temperature, and the ash removal time is 25 - 35 s.
[0058] Step S31: Rinse the single-crystal superalloy casting after ash removal with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0059] Step S4: Perform neutralization on the single-crystal superalloy casting after ash removal; The neutralization process is as follows: Immerse the single-crystal superalloy casting after ash removal in the neutralization solution and process it at room temperature for 1 - 2 min; among them, the neutralization solution is a sodium carbonate solution, and the content of sodium carbonate is 30 - 60 g / L.
[0060] Step S41: Rinse the single-crystal superalloy casting after neutralization with tap water. The rinsing temperature is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0061] Step S5: Perform ultrasonic cleaning and drying on the single-crystal superalloy casting after neutralization.
[0062] Among them, the frequency of the ultrasonic wave is 40 - 100 kHz, the power density of the ultrasonic wave is 0.3 - 0.5 W / cm², the cleaning temperature is 40 - 80 °C, the cleaning time is 3 - 10 minutes, and the drying temperature is 80 - 100 °C.
[0063] Before drying, step S51 is also performed: rinsing the single-crystal superalloy casting after ultrasonic cleaning with deionized water. The temperature of the rinsing is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
[0064] Example 5 As Figure 1 shown, a device for grain corrosion of single-crystal superalloy castings includes a chemical corrosion tank 1, an electrochemical corrosion tank 2, an ash removal tank 3, a neutralization tank 4, an ultrasonic cleaning tank 5, and a drying tank 6 arranged in sequence. A first cleaning tank 7 is respectively arranged between the chemical corrosion tank 1 and the electrochemical corrosion tank 2, and between the electrochemical corrosion tank 2 and the ash removal tank 3. Second cleaning tanks 8 are respectively arranged between the ash removal tank 3 and the neutralization tank 4, between the neutralization tank 4 and the ultrasonic cleaning tank 5, and between the ultrasonic cleaning tank 5 and the drying tank 6.
[0065] Among them, a first chemical corrosion barrel 11, a second chemical corrosion barrel 12, and a first rinsing barrel 13 are arranged in the chemical corrosion tank 1. Heating mechanisms are installed on the first chemical corrosion barrel 11, the second chemical corrosion barrel 12, and the first rinsing barrel 13, and the heating mechanisms are used to heat the liquids in the first chemical corrosion barrel 11, the second chemical corrosion barrel 12, and the first rinsing barrel 13. Different chemical corrosion liquids are respectively contained in the first chemical corrosion barrel 11 and the second chemical corrosion barrel 12 to facilitate selecting a suitable formula according to the workpiece and avoid waste of chemicals caused by replacing the chemical corrosion liquid.
[0066] A first electrochemical corrosion barrel 21, a second electrochemical corrosion barrel 22, and a second rinsing barrel 23 are arranged in the electrochemical corrosion tank 2. Heating mechanisms are installed on the first electrochemical corrosion barrel 21, the second electrochemical corrosion barrel 22, and the second rinsing barrel 23, and the heating mechanisms are used to heat the liquids in the first electrochemical corrosion barrel 21, the second electrochemical corrosion barrel 22, and the second rinsing barrel 23. Different electrochemical corrosion liquids are respectively contained in the first electrochemical corrosion barrel 21 and the second electrochemical corrosion barrel 22 to facilitate selecting a suitable formula according to the workpiece and avoid waste of chemicals caused by replacing the chemical corrosion liquid. Positive and negative electrodes are installed in both the first electrochemical corrosion barrel 21 and the second electrochemical corrosion barrel 22, and the positive and negative electrodes are respectively electrically connected to a control power supply through wires.
[0067] An air gun and a water gun are installed in the first cleaning tank 7. The water gun is connected to a tap water storage tank through a high-pressure water pump and is used to provide high-pressure tap water for rinsing; the air gun is connected to an air compressor storage tank through an air pipe and is used to provide high-pressure air for drying.
[0068] The chemical etching tank 1, the electrochemical etching tank 2, and the first cleaning tank 7 are all connected to the air extraction mechanism through pipelines, which are used to timely extract the chemical waste gas therein, avoid affecting the workshop environment, and ensure the safety of operators.
[0069] The ash removal tank 3 and the ultrasonic cleaning tank 5 are both equipped with heating mechanisms, which are used to heat the ash removal solution and the ultrasonic cleaning solution. Bubbling mechanisms are installed at the bottoms of the ash removal tank 3, the neutralization tank 4, the ultrasonic cleaning tank 5, and the second cleaning tank 8. By means of the bubbling mechanisms, the liquid in the tank is in a tumbling state, thereby improving the treatment effect. Among them, the second cleaning tank 8 located downstream of the ultrasonic cleaning tank 5 is connected to the deionized water storage tank.
[0070] The technical solution provided by the embodiment of the present application has at least the following technical effects or advantages: 1. By performing pretreatment on the single-crystal superalloy casting through chemical etching, the uniformity of the surface potential distribution of the workpiece can be improved, the surface state of the workpiece can be optimized, the corrosion effect of electrochemical etching can be improved, and the recognition rate of grain boundaries can be increased; 2. By performing ash removal treatment, the corrosion products adhering to the surface of the workpiece after electrochemical etching can be removed, which is convenient for observing the grain boundaries of the grains and improving the accuracy and efficiency of inspection; 3. By using a device with multiple treatment tanks to process the single-crystal superalloy casting, the compatibility with complex workpieces can be improved, the concentration gradient of the etching solution in manual operation can be avoided, and the reproducibility of detection can be increased; 4. By controlling the electrochemical etching through the potentiostatic method, the uniformity of the electrochemical etching can be improved, unnecessary side reactions can be avoided, and the quality of the workpiece can be ensured.
[0071] The above is only a preferred embodiment of the present invention, and it does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the above-disclosed technical content to be equivalent embodiments within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any brief modification, equivalent change, and modification made to the above embodiment according to the technical essence of the present invention still fall within the scope of the technical solution of the present invention.
Claims
1. A method for grain corrosion of single crystal superalloy castings, characterized in that, It includes the following steps: Step S1: Chemically etch the single-crystal superalloy casting after sandblasting treatment; Step S2: Electrochemically etch the single-crystal superalloy casting after chemical etching treatment; Step S3: Remove ash from the single-crystal superalloy casting after electrochemical etching treatment; Step S4: Neutralize the single-crystal superalloy casting after ash removal treatment; Step S5: Ultrasonically clean and dry the single-crystal superalloy casting after neutralization treatment.
2. A method for grain corrosion of single crystal superalloy castings according to claim 1, characterized in that After chemical etching treatment and electrochemical etching treatment, the single-crystal superalloy casting is rinsed, flushed, and dried in sequence; after ash removal treatment, neutralization treatment, and ultrasonic cleaning, the single-crystal superalloy casting is rinsed.
3. A method for grain corrosion of single crystal superalloy castings according to claim 1, characterized in that, The chemical etching treatment process is as follows: Immerse the single-crystal superalloy casting after sandblasting treatment in the chemical etching solution and treat it at a temperature of 30 - 50 °C for 5 - 20 min; among them, the chemical etching solution is a mixed solution of ferric chloride and hydrochloric acid, the content of ferric chloride is 300 g / L - 500 g / L, and the content of hydrochloric acid is 30 g / L - 150 g / L.
4. A method for grain corrosion of single crystal superalloy castings according to claim 1, characterized in that, The electrochemical corrosion treatment process is as follows: Immerse the single crystal superalloy casting after chemical corrosion treatment into the electrochemical corrosion solution, and treat it at a temperature of 20 - 50 °C for 3 - 20 min. The electrochemical corrosion parameters are a voltage of 3 - 5 V or a current density of 0.2 - 1 mA / mm 2 ; Among them, the electrochemical etching solution is a mixed solution of sulfuric acid and phosphoric acid, and the ratio of sulfuric acid to phosphoric acid is 1:3 - 1:5; Or the electrochemical etching solution is a mixed solution of glacial acetic acid, ethylene glycol, phosphoric acid, and deionized water. By volume, glacial acetic acid is 10% - 20%, ethylene glycol is 10% - 20%, phosphoric acid is 40% - 60%, and the balance is deionized water.
5. A method for grain corrosion of single crystal superalloy castings according to claim 1, characterized in that, The ash removal treatment process is as follows: Immerse the single-crystal superalloy casting after electrochemical etching treatment in the ash removal solution, where the ash removal solution is a sodium hydroxide solution, the content of sodium hydroxide is 44 - 55 g / L, the ash removal temperature is 60 - 80 °C at this time, and the ash removal time is 15 - 25 min; Or the ash removal solution is a sodium gluconate solution, the content of sodium gluconate is 44 - 55 g / L, the ash removal temperature is 60 - 80 °C at this time, and the ash removal time is 15 - 25 min; Or the ash removal solution is a nitric acid solution, the content of nitric acid is 400 - 600 g / L, the ash removal temperature is at room temperature at this time, and the ash removal time is 25 - 35 s.
6. A method for grain corrosion of single crystal superalloy castings according to claim 1, characterized in that, The neutralization treatment process is as follows: Immerse the single-crystal superalloy casting after ash removal treatment in the neutralization solution and treat it at room temperature for 1 - 2 min; among them, the neutralization solution is a sodium carbonate solution, and the content of sodium carbonate is 30 - 60 g / L.
7. A method for grain corrosion of single crystal superalloy castings according to claim 2, characterized in that, The temperature of the rinsing is 30 - 50 °C, and the rinsing time is 0.5 - 2 min.
8. An apparatus for implementing the grain corrosion method of any single crystal superalloy casting of claims 1-7, characterized in that, It includes a chemically etched tank, an electrochemically etched tank, an ash removal tank, a neutralization tank, an ultrasonic cleaning tank, and a drying tank arranged in sequence. A first cleaning tank is respectively arranged between the chemically etched tank and the electrochemically etched tank, and between the electrochemically etched tank and the ash removal tank; a second cleaning tank is respectively arranged between the ash removal tank and the neutralization tank, between the neutralization tank and the ultrasonic cleaning tank, and between the ultrasonic cleaning tank and the drying tank.
9. An apparatus for grain corrosion of single crystal superalloy castings according to claim 8, characterized in that, The chemical etching tank, the electrochemical etching tank, the ash removal tank, and the ultrasonic cleaning tank are all provided with heating mechanisms; an air gun and a water gun are arranged in the first cleaning tank; the second cleaning tank, the ash removal tank, the neutralization tank, and the ultrasonic cleaning tank are all provided with bubbling mechanisms; the chemical etching tank, the electrochemical etching tank, and the first cleaning tank are all connected to an air extraction mechanism through pipelines; electrodes are arranged in the electrochemical etching tank.
10. A device for grain corrosion of single crystal superalloy castings according to claim 8, characterized in that, A first chemical etching barrel, a second chemical etching barrel, and a first rinsing barrel are arranged in the chemical etching tank; a first electrochemical etching barrel, a second electrochemical etching barrel, and a second rinsing barrel are arranged in the electrochemical etching tank.