Ion implantation method for alloy steel oil separation cover of aviation hydraulic pump

Abstract

The invention discloses an ion implantation method for an alloy steel oil separation cover of an aviation hydraulic pump. The ion implantation method is characterized by comprising the steps of blank cleaning, blow-drying, charging, vacuumizing, cleaning parameter setting, injection parameter setting, a cleaning stage, an injection stage, program operation ending, discharging and the like. The modified layer is obtained through the ion implantation process on the friction surface of the aviation hydraulic pump oil separation cover, the hardness of the oil separation cover is greatly improved, the wear resistance of the product is relatively improved, and the service life is prolonged; the technological process is stable and reliable, and it is guaranteed that the product flatness and other precision are not affected; the macroscopic morphology of the injection layer is golden yellow, the color is uniform, no piebald exists, the hardness improvement proportion is higher than 10%, and the coating thickness is excellent.

Description

Technical Field

[0001] The invention relates to a material surface treatment technology, in particular to an ion implantation method for an alloy steel oil separator cover of an aviation hydraulic pump. Background Art

[0002] Ion implantation is a new type of surface treatment technology. It uses the ions (gas and metal) generated in the ion source to enter the surface of the workpiece material to be treated at a very high speed under the action of a high voltage electric field. In this process, the lattice atoms on the metal surface will cause cascade collisions, resulting in a high degree of lattice distortion or an amorphous structure, and a reduction in the surface friction coefficient. At the same time, it can be mixed with basic atoms to form a hardened phase, thereby effectively improving the hardness, wear resistance, corrosion resistance and fatigue resistance of the workpiece surface, and ultimately improving the service life of the workpiece. This technology is a high-energy input kinetic process, so the surface layer tissue phase obtained is not restricted by physical metallurgical factors such as traditional alloying rules, and new alloy phases that cannot be obtained by other methods can be obtained. Atomic-level mixing in the matrix can form solid solutions, compounds and new alloys. The ion implantation layer will not crack, peel or fall off like plating and coatings, and no reprocessing and heat treatment are required after implantation. Therefore, it is very suitable for the final surface treatment of precision workpieces and forming tools. It is a clean, pollution-free, non-toxic and environmentally friendly process.

[0003] The oil separator cap is one of the components of the aviation hydraulic pump. It is the key friction pair of the aviation plunger hydraulic pump - the flow distribution pair. The material is 25Cr3MoA and 38CrMoAlA. When the hydraulic pump is braked, the oil separator cap and the rotor rub against each other during high-speed operation. The oil separator cap is a high-pressure force-bearing part in the hydraulic pump. The hardness and wear resistance of the oil separator cap are required to be high. Therefore, it is of great significance to obtain a high-hardness and high-wear-resistant modified layer on the friction surface of the oil separator cap. However, there is no reference to the existing technology or public technology regarding the ion implantation process of 25Cr3MoA, 38CrMoAlA materials and the aviation plunger hydraulic pump oil separator cap. Summary of the invention

[0004] The purpose of the present invention is to provide an ion implantation method for an alloy steel oil separator cover of an aviation hydraulic pump in order to solve the problems of low hardness and poor wear resistance of the oil separator cover of an aviation hydraulic pump. The surface modified layer obtained by the invention has the characteristics of high hardness, strong wear resistance, corrosion resistance and excellent fatigue resistance, thereby extending the service life and repair life of the oil separator cover.

[0005] The above technical problem of the present invention is mainly solved by the following technical solution: a method for ion implantation of alloy steel oil separator cover of aviation hydraulic pump, characterized by comprising the following steps:

[0006] A. Cleaning the blank: Soak the oil separator cap in No. 180 gasoline for 30 minutes and then scrub it. Let it dry in the air. Wipe the injection surface of the oil separator cap with anhydrous ethanol. After drying, clean the injection surface with acetone.

[0007] B. Blow dry.

[0008] C. Furnace loading: Install the water-cooling fixture in the vacuum chamber of the ion implanter, and install the oil separator to be injected into the water-cooling fixture.

[0009] D. Vacuuming: Vacuum to (1.0~1.2)×10 -3 After Pa, supply air.

[0010] E. Parameter setting: including cleaning parameter setting and injection parameter setting.

[0011] a. Cleaning parameters include suppression voltage / current, extraction voltage / current, arc voltage / arc current, filament current and cleaning time.

[0012] b. Injection parameters include suppression voltage / current, extraction voltage / current, arc voltage / arc current, filament current and actual injection time.

[0013] F. Cleaning stage: Turn on the power, set the flow rate, filament current, and adjust the arc voltage, extraction voltage, suppression voltage, and acceleration voltage.

[0014] G. Injection stage: control the filament current, adjust the arc voltage, extraction voltage, suppression voltage and acceleration voltage, and perform intermittent injection.

[0015] H. Program operation ends: turn off the head power, suppression power and acceleration power switches.

[0016] I. Take out of the oven. When the molecular pump control window displays "Standby", turn off the molecular pump and mechanical pump to obtain qualified products.

[0017] In the aforementioned aviation hydraulic pump alloy steel oil separator ion implantation method, preferably, in step F, in the cleaning stage: turn on the head power supply, suppression power supply and acceleration power supply switches, set the flow rate to 7sccm, the filament current to between 8 and 15A, adjust the arc voltage to between (69.5 and 70.5)V, the extraction voltage to between (0.30 and 0.36)KV, the suppression voltage to between (1.0 and 1.2)kV, the acceleration voltage to between (19.5 and 20.5)kV, and the cleaning time to 5min.

[0018] In the aforementioned aviation hydraulic pump alloy steel oil separator ion implantation method, preferably, in step G, in the injection stage: the filament current is between 8 and 15A, the arc voltage is adjusted to between (69.5 and 70.5)V, the extraction voltage is adjusted to between (0.30 and 0.36)KV, the suppression voltage is adjusted to between (1.0 and 1.2)kV, the acceleration voltage is between (69.5 and 70.5)kV, and the injection is intermittent, the injection time is 5min, the interval is 20min, and the total injection time is 75min.

[0019] In the aforementioned ion implantation method for the alloy steel oil separator cover of an aviation hydraulic pump, preferably, the blank is inspected after cleaning, and the presence of any spots on the implanted surface is taken as the criterion.

[0020] In the aforementioned aviation hydraulic pump alloy steel oil separator cap ion implantation method, preferably, the water-cooling fixture is customized in size and shape of the clamping portion according to the model and specification parameters of the processed blank, and a circulating water cooling channel is provided in the water-cooling fixture.

[0021] In the aforementioned ion implantation method for the alloy steel oil separator cover of an aviation hydraulic pump, preferably, in the step D, nitrogen is poured into the furnace after vacuuming, and nitrogen ions are implanted into the surface of the blank under high voltage shock.

[0022] This technical solution designs an ion implantation process to address the current situation of low surface hardness and poor wear resistance of the oil distributor cover of aviation hydraulic pumps made of 25Cr3MoA and 38CrMoAlA materials. Cleaning and implantation parameters are formulated according to the surface characteristics of the material. Through reasonable processes and optimal solvent configuration, efficient, fast and low-cost pre-treatment of the blank is carried out; the treated parts are cooled during the process through the design of a water-cooling fixture; nitrogen ions are evenly and omnidirectionally injected into the surface of the blank under a vacuum state; due to the large amount of energy that will cause the blank to heat up during continuous injection, although the water-cooling fixture is continuously cooling the blank, the cooling effect of the water-cooling fixture during the continuous injection process cannot meet the process requirements. If the temperature of the blank is too high at this time, the nitride layer on the injection surface will be destroyed (that is, a nitride layer existing before the injection of this product). The intermittent injection process step design of this method avoids deformation of the injection surface of the blank due to excessive temperature, prevents changes in flatness, and meets the process requirements.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: a modified layer is obtained through an ion implantation process on the friction surface of the oil separator cover of an aviation hydraulic pump, which greatly improves the hardness of the oil separator cover, relatively improves the wear resistance of the product, and extends the service life; the process is stable and reliable, ensuring that the precision of the product such as flatness is not affected; the macroscopic morphology of the implanted layer is golden yellow and uniform in color, without spots, the hardness increase ratio is higher than 10%, and the coating thickness is excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1It is a process flow chart of the present invention.

[0025] Figure 2 The present invention is a schematic diagram of the structure of an oil distributor cover part (ion implantation site) of a certain aviation hydraulic pump.

[0026] Figure 3 This is a color comparison diagram of an oil separator cap injection surface before and after the process is performed. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further specifically described below through embodiments and in conjunction with the accompanying drawings.

[0028] This embodiment provides an ion implantation method for an alloy steel oil separator cover of an aviation hydraulic pump, the main process of which is as follows: Figure 1 As shown, the oil distributor cap parts of a certain aircraft hydraulic pump are as follows Figure 2 As shown, it includes the following steps and contents:

[0029] A. Cleaning the blank: Soak the oil separator cap in No. 180 gasoline for 30 minutes and then scrub it. Let it dry naturally in the air. Wipe the surface of the oil separator cap to be injected with anhydrous ethanol. After drying, clean the surface to be injected with acetone to thoroughly and quickly remove the oil stains and residues on the surface of the oil separator cap blank.

[0030] After cleaning the blank, check it to make sure there are no spots on the injection surface.

[0031] B. Blow dry with clean air. Blow the cleaned oil separator cover for 3 minutes to 5 minutes.

[0032] C. Furnace loading: Install the water-cooling fixture in the vacuum chamber of the ion implanter, and install the oil-distributing cover to be injected into the water-cooling fixture. The size and shape of the clamping part of the water-cooling fixture are customized according to the model and specification parameters of the processed blank. The water-cooling fixture is equipped with a circulating water cooling channel. During operation, flowing water passes through the middle of the fixture, and the water flow circulates continuously to achieve the effect of cooling the parts.

[0033] D. Vacuuming: First vacuum to (1.0~1.2)×10 -3 After Pa, open the gas supply bottle switch to supply nitrogen, fill the nitrogen into the furnace, and inject nitrogen ions into the surface of the blank under high voltage shock.

[0034] E. Parameter setting: including cleaning parameter setting and injection parameter setting;

[0035] a. Cleaning parameters include suppression voltage / current, extraction voltage / current, arc voltage / arc current, filament current and cleaning time.

[0036] b. Injection parameters include suppression voltage / current, extraction voltage / current, arc voltage / arc current, filament current and actual injection time.

[0037] The process parameters of the running program are shown in Table 1

[0038] Table 1 Ion implantation process parameters

[0039]

[0040] F. Cleaning stage: Turn on the head power, suppression power and acceleration power switches, set the flow rate, filament current, and adjust the arc voltage, extraction voltage, suppression voltage and acceleration voltage. Specifically, set the flow rate to 7sccm, the filament current to between 8 and 15A, adjust the arc voltage to between (69.5 and 70.5)V, the extraction voltage to between (0.30 and 0.36)KV, the suppression voltage to between (1.0 and 1.2)kV, the acceleration voltage to between (19.5 and 20.5)kV, and the cleaning time to 5min.

[0041] G. Injection stage: control the filament current, adjust the arc voltage, extraction voltage, suppression voltage and acceleration voltage, and inject intermittently. The specific parameters are: the filament current is between 8 and 15A, the arc voltage is adjusted to between (69.5 and 70.5)V, the extraction voltage is adjusted to between (0.30 and 0.36)KV, the suppression voltage is adjusted to between (1.0 and 1.2)kV, and the acceleration voltage is between (69.5 and 70.5)kV.

[0042] Intermittent injection, injection time is 5 minutes, interval is 20 minutes, total injection time is 75 minutes.

[0043] H. Program operation ends: turn off the head power, suppression power and acceleration power switches.

[0044] I. Take out of the oven. When the molecular pump control window displays "Standby", turn off the molecular pump and mechanical pump to obtain qualified products.

[0045] After inspection:

[0046] The macroscopic appearance of the injection layer on the oil separation cap is golden yellow and uniform in color, without spots. Figure 3 shown.

[0047] The hardness requirement is that the Vickers microhardness after injection is HV0.025, and the increase ratio is not less than 10%. The hardness value on the injection layer of the oil separator cap is shown in Table 2, and the coating thickness is about 1μm.

[0048] Table 2 Hardness value table of ion implantation layer of oil separation cover

[0049]

[0050] The above embodiments are for explanation of the present invention, not for limitation of the present invention, and the described embodiments are only a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Claims

1. A method for ion implantation of alloy steel oil separator cap of aviation hydraulic pump, characterized in that The following steps are involved: A. Cleaning the blank: Soak the oil separator cap in No. 180 gasoline for 30 minutes and then scrub it. Dry it in the air, wipe the surface of the oil separator cap to be injected with anhydrous ethanol, and then clean it with acetone after drying. B. Blow dry; C. Furnace loading: Install the water-cooling fixture in the vacuum chamber of the ion implanter, and install the oil separator to be injected into the water-cooling fixture; D. Vacuuming: Vacuum to (1.0~1.2)×10 -3 After Pa, gas supply; E. Parameter setting: including cleaning parameter setting and injection parameter setting; a. Cleaning parameters include suppression voltage / current, extraction voltage / current, arc voltage / arc current, filament current and cleaning time; b. Injection parameters include suppression voltage / current, extraction voltage / current, arc voltage / arc current, filament current and actual injection time; F. Cleaning stage: Turn on the power, set the flow rate, filament current, and adjust the arc voltage, extraction voltage, suppression voltage, and acceleration voltage; G. Injection stage: control the filament current, adjust the arc voltage, extraction voltage, suppression voltage and acceleration voltage, and perform intermittent injection; H. Program operation ends: turn off the head power, inhibit power and accelerate power switches; I. Take out of the oven. When the molecular pump control window displays "Standby", turn off the molecular pump and mechanical pump to obtain qualified products.

2. The ion implantation method for the alloy steel oil separator cover of an aviation hydraulic pump according to claim 1 is characterized in that: In step F, cleaning stage: turn on the head power, suppression power and acceleration power switches, set the flow rate to 7sccm, the filament current to between 8 and 15A, adjust the arc voltage to between (69.5 and 70.5)V, the extraction voltage to between (0.30 and 0.36)KV, the suppression voltage to between (1.0 and 1.2)kV, the acceleration voltage to between (19.5 and 20.5)kV, and the cleaning time to 5min.

3. The ion implantation method for the alloy steel oil separator cover of an aviation hydraulic pump according to claim 1 is characterized in that: In step G, during the injection phase: the filament current is between 8 and 15 A, the arc voltage is adjusted to between (69.5 and 70.5) V, the extraction voltage is adjusted to between (0.30 and 0.36) KV, the suppression voltage is adjusted to between (1.0 and 1.2) kV, the acceleration voltage is between (69.5 and 70.5) kV, and the injection is intermittent. The injection time is 5 minutes, the interval is 20 minutes, and the total injection time is 75 minutes.

4. The ion implantation method for an alloy steel oil separator cover of an aviation hydraulic pump according to claim 1, characterized in that: After the cleaning of the blank, an inspection is performed to determine whether there are any spots on the injection surface.

5. The ion implantation method for the alloy steel oil separator cover of an aviation hydraulic pump according to claim 1, characterized in that: The water-cooling fixture is customized in size and shape of the clamping part according to the model and specification parameters of the processed blank, and a circulating water cooling channel is provided in the water-cooling fixture.

6. The method for ion implantation of alloy steel oil separator cap of aviation hydraulic pump according to claim 1, characterized in that: In the step D, nitrogen is poured into the furnace after vacuuming, and nitrogen ions are injected into the surface of the blank under high voltage shock.

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