CN109371392B - Nickel-based wear-resistant corrosion-resistant coating composition for marine hydraulic piston rod, coating and preparation method of coating - Google Patents
Nickel-based wear-resistant corrosion-resistant coating composition for marine hydraulic piston rod, coating and preparation method of coating Download PDFInfo
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- CN109371392B CN109371392B CN201811240165.0A CN201811240165A CN109371392B CN 109371392 B CN109371392 B CN 109371392B CN 201811240165 A CN201811240165 A CN 201811240165A CN 109371392 B CN109371392 B CN 109371392B
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C24/00—Coating starting from inorganic powder
- C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
- C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
- C23C24/103—Coating with metallic material, i.e. metals or metal alloys, optionally comprising hard particles, e.g. oxides, carbides or nitrides
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C19/00—Alloys based on nickel or cobalt
- C22C19/03—Alloys based on nickel or cobalt based on nickel
- C22C19/05—Alloys based on nickel or cobalt based on nickel with chromium
- C22C19/058—Alloys based on nickel or cobalt based on nickel with chromium without Mo and W
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- Mechanical Engineering (AREA)
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- Pistons, Piston Rings, And Cylinders (AREA)
Abstract
The invention discloses a formula of a nickel-based wear-resistant corrosion-resistant coating for a maritime hydraulic piston rod, a coating and a preparation method thereofThe method is carried out. The coating comprises the following components in percentage by mass: 85-95% of metal Ta powder: 1 to 15% of CeO2Rare earth oxide powder: 0.2 to 3 percent. The formula is used as a laser cladding material, the powder is sequentially fed to the surface of a steel base material of the piston rod after pretreatment through an automatic powder feeder, and meanwhile, the powder is cladded on the surface of the piston rod through laser radiation, and finally, a coating with the thickness of 0.5-2.0 mm is formed.
Description
Technical Field
The invention relates to a formula of a nickel-based wear-resistant corrosion-resistant coating for a hydraulic piston rod for maritime work, a coating and a preparation method thereof.
Background
The piston rod is one of key core components of a hydraulic gate hoist for ocean engineering and coastal hydraulic engineering, and the base material of the piston rod is mainly carbon steel, alloy steel or quenched and tempered steel, and a small amount of stainless steel. The piston rod is seriously corroded due to long-term exposure to severe environments such as corrosive seawater, humid atmosphere, sunshine insolation and the like, and in addition, seawater flowing at high speed in a strong tidal zone and gravel carried by the seawater generate strong scouring wear on the surface of the piston rod, so that the surface of the piston rod is easy to generate chemical corrosion and physical wear, the hydraulic system is sealed and invalid, the hydraulic system cannot be used due to oil leakage, and the normal opening and closing of the gate are further influenced. The piston rod therefore usually needs to be surface protected to improve its corrosion and wear resistance.
At present, most of the piston rod surface protection technologies are chrome plating or nickel plating, wherein chrome plating is mainly used. However, hexavalent chromium has serious environmental pollution and health hazard, and the chromium electroplating process is banned and finally eliminated internationally and in China. Therefore, the technology for replacing chromium electroplating becomes a research hotspot in recent years, flame spraying, plasma spraying, argon arc or plasma surfacing and the like are mainly used at present, but the flame spraying and the plasma coating have the defects of high porosity, low bonding strength, coating cracks and the like, and are easy to generate pitting corrosion, bubbling and coating falling; the overlay welding layer has the problems of high dilution rate, serious tissue defects, insufficient fatigue strength and the like. Laser cladding is an advanced and green surface technology and is expected to become one of new technologies for replacing chromium electroplating.
Disclosure of Invention
Aiming at the problems of the existing marine piston rod corrosion and abrasion protection coating technology, the invention provides a nickel-based wear-resistant and corrosion-resistant coating formula for a marine hydraulic piston rod, a coating and a preparation method thereof. The coating obtained by the invention is uniform and compact, is metallurgically bonded with a base material, has low dilution rate, and has excellent corrosion resistance, abrasion resistance and impact toughness.
The technical scheme of the invention is as follows:
a formula of a nickel-based wear-resistant corrosion-resistant coating for a maritime work hydraulic piston rod comprises the following components:
component A: NiCrBSi alloy powder with the particle size of 45-125 mu m; component B: the rare earth modifier nano cerium oxide with the purity not lower than 99 percent has the granularity of 40-90 nm; component C: micro-nano metal tantalum powder with the purity not lower than 99.99% and the granularity of 80-200 nm; and the component A is 85-95 wt%, the component B is 0.2-3 wt%, and the component C is 5-10 wt%.
In the above technical scheme, the NiCrBSi alloy powder is: the chemical components by mass percent are as follows: 0.45% of C, 2.3% of B, 3.9% of Si, 11.0% of Cr, 2.9% of Fe and the balance of Ni.
Further, the mass ratio of the component C to the component B is more than or equal to 5: 1.
The nickel-based wear-resistant and corrosion-resistant coating for the marine hydraulic piston rod is prepared from the raw materials by a laser cladding process on the surface of a piston rod workpiece. The method specifically comprises the following steps:
the method comprises the following steps: mixing the coating formula according to a ratio, and mixing in a ball mill for 20-72 hours to obtain uniform composite powder; placing the mixture in a drying oven, drying the mixture for 1 to 3 hours at the temperature of between 100 and 150 ℃;
step two: piston rod surface pretreatment
Clamping a piston rod on a horizontal rotary table, removing oil, dirt and rust on the surface of the piston rod, and cleaning the piston rod by using alcohol or acetone; heating the piston rod to 100-120 ℃ by using an induction heater;
step three: laser cladding preparation nickel-based wear-resistant corrosion-resistant coating
(1) Setting the linear velocity of the moving transfer to be 10 mm/s;
(2) and (3) filling the composite powder into an automatic powder feeder, feeding the powder to the surface of the piston rod in the step two by using high-purity nitrogen with the purity of not less than 99.99%, simultaneously melting the powder on the surface of the piston rod by adopting coaxial laser equipment to form a molten pool, and cooling and solidifying to obtain the uniform and compact nickel-based wear-resistant corrosion-resistant coating.
The thickness of the nickel-based anti-wear and anti-corrosion coating is 0.5-2.0 mm.
The parameters of the laser cladding process in the third step are as follows: the diameter of a light spot is 5mm, the lap joint rate is 50%, the laser power is 1-4 kw, the scanning speed of a melting head is 20 mm/s, and the powder feeding rate is 20-100 g/min.
The surface coating of the piston rod after laser cladding can be machined conventionally, so that the surface size and roughness of the piston rod can meet specific requirements.
The invention has the following advantages and characteristics:
(1) the alloy powder formula provided by the invention contains nickel-based alloy components with excellent corrosion resistance, hard ceramic components with excellent wear resistance and components for improving the texture structure and toughness of the coating, so that the coating has excellent corrosion resistance, wear resistance and impact toughness, and is suitable for strong corrosion and strong erosive wear environments in marine environments.
(2) The invention adopts the laser cladding process, the cladding layer and the piston rod substrate are completely metallurgically bonded, the coating is compact and uniform, and the defects of more cracks or pores, poor bonding strength with the substrate and the like of an electroplated layer and a thermal spraying coating are overcome.
(3) The laser cladding heating speed is high, the matrix heat affected zone is small, and the cladding layer dilution rate is low (generally less than 5%). Compared with the traditional metallurgical bonding coating such as plasma surfacing, the laser cladding layer has low dilution rate, fine grain size and better corrosion resistance and wear resistance.
Detailed Description
Example 1
(1) Coating formula components and proportion
NiCrBSi alloy powder with the particle size of 45-125 mu m (the chemical components of the NiCrBSi alloy powder are, by mass, 0.45 percent of C, 2.3 percent of B, 3.9 percent of Si, 11.0 percent of Cr11, 2.9 percent of Fe2, and the balance of Ni), and a nano cerium oxide rare earth modifier (CeO)2The purity is more than or equal to 99 percent, and the granularity is 40-90 nm) and micro-nano metal tantalum powder (Ta, the purity is more than or equal to 99.99 percent, and the granularity is 80-200 nm) are mixed. The mass percentage is as follows: NiCrBSi alloy: 88% of micro-nano metal Ta powder: 10% of CeO2Nano rare earth oxide powder: 2 percent. And mixed in a ball mill for 45 hours to obtain uniform composite powder. And (3) placing the composite powder in a drying oven, and drying for 2h at 100 ℃ for later use.
(2) Piston rod surface pretreatment
Clamping a piston rod made of 45 steel on a horizontal rotary table, removing oil, dirt and rust on the surface of the piston rod, and cleaning the piston rod by using alcohol or acetone; the piston rod was heated to 100 ℃ with an induction heater.
(3) Laser cladding preparation nickel-based wear-resistant corrosion-resistant coating
The laser cladding process parameters are as follows: the diameter of a light spot is 5mm, the lapping rate is 50%, the laser power is 3.5 kw, the scanning speed of a melting head is 20 mm/s, and the powder feeding speed is 150 g/min.
The linear speed of the dynamic transfer is set to 10 mm/s. The composite powder was charged into an automatic powder feeder and the powder was fed to the surface of the piston rod with 99.99% high purity nitrogen. Simultaneously, coaxial laser equipment is adopted to melt the powder on the surface of the piston rod to form a molten pool, and the thickness of the molten pool is about the thickness after cooling and solidification1.2mm of a dense cladding alloy layer; the coating is metallurgically bonded, the bonding is good, the corrosion potential is-302 mV, and the coating hardness is 577HV0.2
(4) Machining piston rod size and roughness
And performing conventional machining on the surface coating of the piston rod subjected to laser cladding to enable the roughness to reach Ra0.1 mu m.
Example 2
(1) Coating formula components and proportion
NiCrBSi alloy powder with the particle size of 45-125 mu m (the chemical components of the NiCrBSi alloy powder are, by mass, 0.45 percent of C, 2.3 percent of B, 3.9 percent of Si, 11.0 percent of Cr11, 2.9 percent of Fe2, and the balance of Ni), and a nano cerium oxide rare earth modifier (CeO)2And the purity is more than or equal to 99 percent) and the micro-nano metal tantalum powder (Ta, the purity is more than or equal to 99.99 percent) are mixed. The mass percentage is as follows: NiCrBSi alloy: 94% of micro-nano metal Ta powder: 5% of CeO2Nano rare earth oxide powder: 1 percent. And mixed in a ball mill for 30 hours to obtain uniform composite powder. And (3) placing the composite powder in a drying oven, and drying at 120 ℃ for 1h for later use.
(2) Piston rod surface pretreatment
Clamping a piston rod made of Q345 steel on a horizontal rotary table, removing oil, dirt and rust on the surface of the piston rod, and cleaning the piston rod by using alcohol or acetone; the piston rod was heated to 100 ℃ with an induction heater.
(3) Laser cladding preparation nickel-based wear-resistant corrosion-resistant coating
The laser cladding process parameters are as follows: the diameter of a light spot is 5mm, the lapping rate is 50%, the laser power is 3 kw, the scanning speed of a fusion head is 20 mm/s, and the powder feeding speed is 100 g/min.
The linear speed of the dynamic transfer is set to 10 mm/s. The composite powder was charged into an automatic powder feeder and the powder was fed to the surface of the piston rod with 99.99% high purity nitrogen. Meanwhile, coaxial laser equipment is adopted to melt the powder on the surface of the piston rod to form a molten pool, and a compact cladding alloy layer with the thickness of about 0.8 mm is obtained after cooling and solidification; the coating is metallurgically bonded, the bonding is good, the corrosion potential is-323 mV, and the coating hardness is 611HV0.2
(4) Machining piston rod size and roughness
And performing conventional machining on the surface coating of the piston rod subjected to laser cladding to enable the roughness to reach Ra0.1 mu m.
Example 3
(1) Coating formula components and proportion
NiCrBSi alloy powder with the particle size of 45-125 mu m (the chemical components of the NiCrBSi alloy powder are, by mass, 0.45 percent of C, 2.3 percent of B, 3.9 percent of Si, 11.0 percent of Cr11, 2.9 percent of Fe2, and the balance of Ni), and a nano cerium oxide rare earth modifier (CeO)2And the purity is more than or equal to 99 percent) and the micro-nano metal tantalum powder (Ta, the purity is more than or equal to 99.99 percent) are mixed. The mass percentage is as follows: NiCrBSi alloy: 85.2% of micro-nano metal Ta powder: 6% of CeO2Nano rare earth oxide powder: 0.8 percent. And mixed in a ball mill for 55 hours to obtain uniform composite powder. And (3) placing the composite powder in a drying oven, and drying for 2.5h at 150 ℃ for later use.
(2) Piston rod surface pretreatment
Clamping a piston rod made of 2205 stainless steel on a horizontal rotary table, removing oil, dirt and rust on the surface of the piston rod, and cleaning the piston rod by using alcohol or acetone; the piston rod was heated to 100 ℃ with an induction heater.
(3) Laser cladding preparation nickel-based wear-resistant corrosion-resistant coating
The laser cladding process parameters are as follows: the diameter of a light spot is 5mm, the lapping rate is 50%, the laser power is 2.5 kw, the scanning speed of a melting head is 20 mm/s, and the powder feeding speed is 50 g/min.
The linear speed of the dynamic transfer is set to 10 mm/s. The composite powder was charged into an automatic powder feeder and the powder was fed to the surface of the piston rod with 99.99% high purity nitrogen. Meanwhile, coaxial laser equipment is adopted to melt the powder on the surface of the piston rod to form a molten pool, and a compact cladding alloy layer with the thickness of about 0.5 mm is obtained after cooling and solidification; the coating is metallurgically bonded, the bonding is good, the corrosion potential is-335 mV, and the coating hardness is 662HV0.2
(4) Machining piston rod size and roughness
And performing conventional machining on the surface coating of the piston rod subjected to laser cladding to enable the roughness to reach Ra0.1 mu m.
Claims (6)
1. The nickel-based wear-resistant corrosion-resistant coating composition for the marine hydraulic piston rod is characterized by comprising the following components:
component A: NiCrBSi alloy powder with the particle size of 45-125 mu m; component B: the rare earth modifier nano cerium oxide with the purity not lower than 99 percent has the granularity of 40-90 nm; component C: micro-nano metal tantalum powder with the purity not lower than 99.99% and the granularity of 80-200 nm; and the component A is 85-95 wt%, the component B is 0.2-3 wt%, and the component C is 5-10 wt%; the NiCrBSi alloy powder comprises the following components: the chemical components by mass percent are as follows: 0.45% of C, 2.3% of B, 3.9% of Si, 11.0% of Cr, 2.9% of Fe and the balance of Ni.
2. The composition of the nickel-based anti-wear and anti-corrosion coating for the marine hydraulic piston rod as claimed in claim 1, wherein the mass ratio of the component C to the component B is not less than 5: 1.
3. A nickel-based wear-resistant corrosion-resistant coating for a maritime hydraulic piston rod is characterized by being prepared on the surface of a piston rod workpiece by a laser cladding process by taking the composition as claimed in any one of claims 1-2 as a raw material.
4. The method for preparing the nickel-based anti-wear and anti-corrosion coating for the marine hydraulic piston rod according to claim 3, comprising the steps of:
the method comprises the following steps: mixing the coating composition according to a ratio, and mixing in a ball mill for 20-72 hours to obtain uniform composite powder; placing the mixture in a drying oven, drying the mixture for 1 to 3 hours at the temperature of between 100 and 150 ℃;
step two: piston rod surface pretreatment
Clamping a piston rod on a horizontal rotary table, removing oil, dirt and rust on the surface of the piston rod, and cleaning the piston rod by using alcohol or acetone; heating the piston rod to 100-120 ℃ by using an induction heater;
step three: laser cladding preparation nickel-based wear-resistant corrosion-resistant coating
(1) Setting the linear velocity of the moving transfer to be 10 mm/s;
(2) and (3) filling the composite powder into an automatic powder feeder, feeding the powder to the surface of the piston rod in the step two by using high-purity nitrogen with the purity of not less than 99.99%, simultaneously melting the powder on the surface of the piston rod by adopting coaxial laser equipment to form a molten pool, and cooling and solidifying to obtain the uniform and compact nickel-based wear-resistant corrosion-resistant coating.
5. The preparation method of the nickel-based anti-wear and anti-corrosion coating for the marine hydraulic piston rod as claimed in claim 4, wherein the thickness of the nickel-based anti-wear and anti-corrosion coating is 0.5-2.0 mm.
6. The preparation method of the nickel-based anti-wear and anti-corrosion coating for the marine hydraulic piston rod as claimed in claim 4, wherein the parameters of the laser cladding process in the third step are as follows: the diameter of a light spot is 5mm, the lap joint rate is 50%, the laser power is 1-4 kw, the scanning speed of a melting head is 20 mm/s, and the powder feeding rate is 20-100 g/min.
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| CN110042387A (en) * | 2019-04-01 | 2019-07-23 | 西安理工大学 | A kind of 40Cr steel surface build-up wear-resistant layer and preparation method thereof |
| CN112122607B (en) * | 2020-10-10 | 2023-05-09 | 哈尔滨工程大学 | Material adding and repairing material suitable for ocean oscillation working condition and stability-shape regulation and control method of molten pool |
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| CN1298889C (en) * | 2003-07-30 | 2007-02-07 | 合肥工业大学 | Nickel base self-fusible alloy-rare earth composite coating material and its preparing method |
| CN106521488A (en) * | 2016-11-18 | 2017-03-22 | 无锡明盛纺织机械有限公司 | Laser cladding preparation method of NiCrBSiCe corrosion-resistant sucker rod |
| CN108203824B (en) * | 2017-12-29 | 2019-12-03 | 常州力安液压设备有限公司 | A kind of laser gain material manufacture piston rod wear-and corrosion-resistant surface layer method |
| CN108203825B (en) * | 2018-01-29 | 2020-04-14 | 中国人民解放军陆军装甲兵学院 | Thermal fatigue resistant nickel-based composite coating for monitoring surface damage process of diesel engine cylinder cover and application thereof |
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