CN111548700A - Novel chromium-free self-lubricating coloring aluminum coating for aviation and preparation method and application thereof - Google Patents
Novel chromium-free self-lubricating coloring aluminum coating for aviation and preparation method and application thereof Download PDFInfo
- Publication number
- CN111548700A CN111548700A CN202010340981.XA CN202010340981A CN111548700A CN 111548700 A CN111548700 A CN 111548700A CN 202010340981 A CN202010340981 A CN 202010340981A CN 111548700 A CN111548700 A CN 111548700A
- Authority
- CN
- China
- Prior art keywords
- coating
- lubricating
- aluminum
- fastener
- free self
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D161/00—Coating compositions based on condensation polymers of aldehydes or ketones; Coating compositions based on derivatives of such polymers
- C09D161/04—Condensation polymers of aldehydes or ketones with phenols only
- C09D161/06—Condensation polymers of aldehydes or ketones with phenols only of aldehydes with phenols
- C09D161/14—Modified phenol-aldehyde condensates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D5/00—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D5/00—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
- B05D5/12—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures to obtain a coating with specific electrical properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/24—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
- C09D5/08—Anti-corrosive paints
- C09D5/10—Anti-corrosive paints containing metal dust
- C09D5/103—Anti-corrosive paints containing metal dust containing Al
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
- C09D7/40—Additives
- C09D7/60—Additives non-macromolecular
- C09D7/61—Additives non-macromolecular inorganic
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
- C09D7/40—Additives
- C09D7/60—Additives non-macromolecular
- C09D7/63—Additives non-macromolecular organic
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D7/00—Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
- C09D7/40—Additives
- C09D7/65—Additives macromolecular
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/02—Elements
- C08K3/08—Metals
- C08K2003/0812—Aluminium
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/30—Sulfur-, selenium- or tellurium-containing compounds
- C08K2003/3009—Sulfides
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Paints Or Removers (AREA)
Abstract
The invention provides a novel chromium-free self-lubricating colored aluminum coating for aviation, and a preparation method and application thereof, wherein the self-lubricating aluminum coating comprises the following components: the modified phenolic resin, the lubricant, the moisture absorbent, the stabilizer, the aluminum powder, the organic solvent and the bonding agent are applied, when in use, an air spray gun (HVLP) or an electrostatic spray gun is used for spraying the aluminum coating on the surface of the pretreated part, and after the surface of the coating is dried, the coating is cured for 60min at the temperature of 190 +/-10 ℃ to form the coating. The coating thickness formed by the coating method can control the coating thickness of all the working surfaces of the external thread fastener to be between 5 and 12.7 microns, and the coating thickness of all the working surfaces of the internal thread fastener to be between 5 and 20 microns. The aluminum coating disclosed by the invention does not contain heavy metal chromium, and meets the environmental protection requirement; the coating has good binding force, can resist various hydraulic oil, paint remover and cleaning agent without deterioration, can provide good anticorrosion effect for parts such as titanium alloy fasteners and the like, and improves the reliability of products; the coating has a self-lubricating function, and can greatly reduce the mounting torque and the dismounting torque.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to the field of coatings, in particular to a novel chromium-free self-lubricating colored aluminum coating for aviation and a preparation method and application thereof.
[ background of the invention ]
With the continuous development of military and civil aerospace aircrafts, the aviation manufacturing industry puts higher requirements on the load carrying capacity and the service life of the aircrafts, and the titanium alloy high-strength fastening piece continuously replaces the traditional aerospace fastening piece. However, when the titanium alloy is in contact with the aluminum alloy with negative potential, the titanium alloy is easy to undergo potential corrosion, so that failures such as 'seizure' and the like occur, and therefore effective protective measures must be taken to ensure the reliability of structural connection. Meanwhile, since the titanium alloy fastener is mostly used for interference fit, the surface protective layer is required to have good bonding force, toughness and lubricity.
The surface protection of the aerospace titanium alloy fastener generally adopts the modes of ion aluminizing, anodizing, chrome plating and the like. However, the chrome plating process tends to cause hydrogen embrittlement of the titanium alloy, resulting in stress embrittlement of the titanium alloy fastener during use. The modes of ion plating aluminum, anodizing and the like have the problems of complex process or unstable process and the like, and are not favorable for the batch engineering application of the titanium alloy fasteners on the airplane structure. In addition, the three surface treatment processes have the defects of high energy consumption, serious pollution and the like, particularly, heavy metal pollution can be caused by chromium plating, and the surface treatment processes are forbidden in a plurality of developed countries. The best protection technology for titanium alloy fasteners is currently to form a dense aluminum coating on the surface, as represented by the Hi-Kote4NC aluminum coating developed by Hi-Shear. The Hi-Kote4NC aluminum coating has good bonding force with a substrate, can resist various environmental media without deterioration, and is widely used for protecting aviation titanium alloy fasteners.
With the development of aviation industry, higher requirements are put forward on the thickness uniformity, the bonding force and the lubricating property of the aluminum coating, and various failures can occur to the aluminum coating under the condition of overhigh assembly torque. Therefore, new aluminum coatings need to be developed, and new coating methods need to be developed to meet the use requirements and environmental protection requirements of products.
[ summary of the invention ]
The invention aims to solve the problems and provides a novel chromium-free self-lubricating colored aluminum coating for aviation, and a preparation method and application thereof.
In order to solve the problems, the invention provides a novel chromium-free self-lubricating coloring aluminum paint for aviation, which is characterized in that the formula composition and the mass fraction of the aluminum paint are as follows, calculated by taking the total mass of the self-lubricating aluminum paint as 100 percent:
modified phenolic resin: 20 to 40 percent of
A first lubricant: 2 to 5 percent
A second lubricant: 5-10 percent
Moisture absorbent: 10 to 20 percent
Aluminum powder: 5-10 percent
A stabilizer: 2 to 5 percent
Binding agent: 1 to 1.5 percent
Organic solvent: and (4) the balance.
Further, the first lubricant is molybdenum disulfide.
Further, the second lubricant is polytetrafluoroethylene.
Further, the moisture absorbent is acetic acid.
Further, the aluminum powder is aluminum powder with fineness of less than 4 μm.
Further, the stabilizer is dibasic lead phosphite.
Further, the binding agent is butyraldehyde.
Further, the organic solvent is butanone.
In addition, the invention also provides a preparation method of the novel chromium-free self-lubricating colored aluminum paint for aviation, which is characterized by comprising the following steps:
A. mixing the aluminum powder, the modified phenolic resin, the organic solvent and the bonding agent in parts, and stirring for 20-30min at the rotating speed of 1000-1500r/min by using a pneumatic stirring gun;
B. adding the first lubricant, the second lubricant, the moisture absorbent and the stabilizer into the A, and stirring for 8-12min at the rotating speed of 1000-2000r/min by using a pneumatic stirring gun;
C. adding B into a grinder, grinding for 50-58min at the rotating speed of 4500-.
In addition, the invention also provides application of the novel chromium-free self-lubricating colored aluminum paint for aviation, which is characterized by comprising the following steps:
a. after the parts are deoiled, blasting sand by using 120-mesh and 220-mesh corundum sand, cleaning by using deionized water, drying and preheating, wherein the preheating temperature is 95 +/-5 ℃;
b. spraying the finished aluminum paint on the pretreated part, drying the surface of the coating, and curing at 190 +/-10 ℃ for 55-65min to form the coating.
The coating of the invention has uniform thickness and can be controlled between 5 and 12.7 mu m; the binding force with the matrix is good, and the performances such as lubricity, corrosion resistance and the like are good; the technical index meets the following standard specification requirements:
NAS4006 aluminum coating issued by the American space standards Committee
EN4473 European Standard "aerospace series-fastener colored aluminum coating-technical Specification
EN4474 European Standard "aerospace series-pigmented aluminum coating-coating Process
BMS10-85 Boeing company "Specification for painted aluminum coating for fasteners-Boeing Material
Hi-Shear294 colored aluminum coating for fastener System
Hi-Shear397 self-lubricating aluminum coating for titanium alloy fastener system
FED-STD-595 Federal color card of America
The aluminum coating disclosed by the invention does not contain heavy metal chromium, and meets the environmental protection requirement; the coating has good binding force, can resist various hydraulic oil, paint remover and cleaning agent without deterioration, can provide good anticorrosion effect for parts such as titanium alloy fasteners and the like, improves the reliability of products, can play a role in potential isolation in connection of different metal material structures, composite material structures and metal and composite material structures of aircrafts, has extremely strong anticorrosion performance, and can improve the connection strength, reliability and service life of the aircrafts; the coating has a self-lubricating function, can reduce the friction coefficient of the connecting pair, can greatly reduce the mounting torque and the dismounting torque, avoids the friction occlusion caused between the thread pairs, ensures that the machine body structure of different materials is more reliably connected, is more convenient to assemble, and improves the maintainability.
[ detailed description ] embodiments
The following examples are further illustrative and supplementary to the present invention and do not limit the present invention in any way.
Specific examples are provided below, where not noted, specific weight averages by weight:
example 1
The preparation method of this example is as follows:
A. mixing 10% of aluminum powder, 20% of modified phenolic resin, 33.5% of butanone serving as an organic solvent and 1.5% of butyraldehyde serving as a binding agent, and stirring for 20-30min at the rotating speed of 1000-1500r/min by using a pneumatic stirring gun;
B. adding 5% of first lubricant molybdenum disulfide, 10% of second lubricant polytetrafluoroethylene, 15% of hygroscopic agent acetic acid and 5% of stabilizer dibasic lead phosphite into the A, and stirring for 10min at the rotating speed of 1000-2000r/min by using a pneumatic stirring gun;
C. and adding the B into a grinding machine, grinding for 55min at the rotating speed of 4500-. The paint color appearance was silvery, similar to the color of code 26380 in FED-STD-595, Federal color card, USA.
The aluminum paint prepared in the embodiment is applied by referring to the following steps:
a. after the parts are deoiled, sand blasting is carried out by using 120-mesh and 220-mesh corundum sand, and the parts are cleaned by using deionized water, dried and preheated, wherein the preheating temperature is 95 ℃.
b. Spraying the finished coating on the pretreated part, drying the surface of the coating, and curing at 190 ℃ for 60min to form the coating. The coating appeared golden yellow, approaching the color of code 33440 in FED-STD-595 Federal color chip.
The obtained self-lubricating aluminum coating is subjected to detection on appearance, thickness, adhesive force, fluid resistance, paint stripping resistance, brittleness, heat resistance, corrosion resistance and self-lubricating performance of the self-lubricating aluminum coating according to the specifications of EN4473 European standard (aerospace series-fastener colored aluminum coating-technical specification), NAS4006 American space navigation standard (aluminum coating) and Hi-Shear397 (self-lubricating aluminum coating of titanium alloy fastener system).
Appearance, visual inspection: visual inspection was conducted under natural scattered light or white transmitted light with no reflected light, the light illumination should be no less than 300Lx (i.e., the illumination of the equivalent part at a distance of 500mm under a 40W fluorescent lamp), and the coating should be smooth, flat, and uniform, with a yellow color approaching that of 33440 in FED-STD-595, Federal color card, USA, and without voids, holes, bubbles, nodules, pits, or other irregularities.
The thickness was measured by microscopy according to GJB 715.6 "thickness of Metal covering layer for fastener test method", and a measurement point was selected at a predetermined measurement site. The method comprises the following steps of randomly selecting 3 measuring points at the thread part of an internal thread fastener, selecting 3 points at the supporting surface part, selecting 2 points at the polished rod part of an external thread fastener, selecting 2 points at the thread part, selecting 2 points at the supporting surface, and enabling the coating thickness of all working surfaces of the external thread fastener to be 5-12.7 microns. The coating thickness of all working surfaces of the internal thread fastener is between 5 and 20 mu m. The remaining surface coating of the fastener is completely covered. Bolt, screw working face: a head support surface, a stem, a thread; the working surface of the nut is as follows: bearing surfaces, threads.
And (4) adopting a drop hammer method (only suitable for the countersunk head bolt) to place the fastener on a static load pressure plate of a drop hammer testing machine to carry out a weight upsetting test. Flattening the head of the fastener or crushing the head of the fastener to the rod diameter, and inspecting the coating condition of the end face of the head under a magnifying lens of 4-6 times without separating the coating from the base metal. A tape method (only suitable for raised head bolts) is adopted, 3M 250 or the same type of tape is pasted on the rod part of the bolt (if the rod part of the bolt is too short, the tape can be pasted on the head part of the bolt), the tape is ensured to be in surface contact with the bolt, a roller with the weight of 1kg is used for rolling repeatedly once during pasting, the tape is pasted evenly and naturally, then the tape is violently torn off perpendicular to the pasting surface of the bolt, the condition of the coating is checked under a magnifying lens of 4-6 times, and the phenomenon that the coating is separated from the base metal does not occur.
And (3) fluid resistance, namely respectively putting RP-3 type aviation fuel oil meeting GB 6537 and YH-15 aviation hydraulic oil meeting GJB1177A into two test tubes, putting a fastener into each test tube, sealing, and storing for 30 days at the temperature of 65 +/-3 ℃. After the fastener is dried, an adhesion test is carried out by adopting a drop hammer method and an adhesive tape method, and the change condition of the hardness of the coating before and after the fastener is soaked is measured by a pencil method according to GB/T6739, so that the coating has no bubbles, and the phenomenon that the coating is separated from the base metal does not occur. The hardness of the coating was determined using the pencil method and the hardness of the coating was reduced by no more than 2 pencil hardness units for the soaked fastener compared to the un-soaked fastener.
And (3) paint stripping resistance, namely soaking the fastening piece in the MIL-R-81294 paint stripping agent, and keeping the fastening piece at the temperature of 25 +/-3 ℃ for 24 hours. The paint remover on the surface of the fastener was cleaned and dried with tap water, the fastener was visually inspected, and the adhesion test was performed by a drop hammer method or a tape method. And the change condition of the hardness of the coating before and after the fastener is soaked is measured by a pencil method according to GB/T6739, the coating has no bubbles, and the phenomenon that the coating is separated from the base metal does not occur. The hardness of the coating was determined using the pencil method and the hardness of the coating was reduced by no more than 2 pencil hardness units for the soaked fastener compared to the un-soaked fastener.
And (3) brittleness, installing 4 fasteners in a 7075-T6 aluminum alloy cushion block, wherein two fasteners are coated with aluminum, two fasteners are not coated with aluminum, the interference amount of the installation aperture is 0.05 mm-0.1 mm, the installation pretightening force is 80% of the rated load, and the fasteners are exposed for 72 hours at the temperature of 150 +/-5 ℃. And after cooling, taking down the fastener, respectively observing the aluminum-coated fastener under 200 times, and comparing the metallographic structure of the aluminum-coated fastener with that of the fastener which is not coated with aluminum, wherein no crack exists in the head fillet and the thread area. There was no significant difference in metallographic structure between the aluminium coated and non-aluminium coated fasteners.
And (3) heat resistance, placing 4 fasteners in an environment with the temperature of 235 +/-5 ℃ and preserving the heat for 4 hours. And then cooling to room temperature in the air, and performing an adhesion test by adopting a drop hammer method and an adhesive tape method, wherein the coating does not have bubbles or cracks and does not have the phenomenon of separation of the coating and the matrix metal.
The corrosion resistance is realized by adopting a method of an acetate spray test and an alternate immersion test, after the test, no obvious corrosion trace exists, and the corrosion degree of a test piece dimple part provided with the aluminum-coated fastener and the lower supporting surface of the fastener head does not exceed the corrosion degree of a corresponding area provided with the cadmium-plated fastener.
And (3) performing a press-in test (self-lubricating property), selecting 5 fasteners with the diameter of 6.35mm, and mounting the fasteners on a 2024-T4 board with the thickness of 12.7mm to ensure the interference between the bolt and the hole to be 0.08-0.12 mm. The mounting hole should be chamfered, the diameter after chamfering is 1.4mm larger than the hole diameter, and the chamfer edge can be rounded with 0.8 mm. And then slowly pressing the test piece into the mounting hole at the speed of 50 +/-6 mm/min until the under-head bearing surface of the bolt is contacted with the mounting plate, and recording the pressing force in the process, wherein the mounting hole and the bolt polished rod are not allowed to be obviously damaged, and the polished rod cannot expose out of the metal matrix.
Example 2
The preparation method of this example is as follows:
A. mixing 8% of aluminum powder, 30% of modified phenolic resin, 30.7% of organic solvent butanone and 1.3% of bonding agent butyraldehyde, and stirring for 20min at the rotating speed of 1000-;
B. adding 3.5% of first lubricant molybdenum disulfide, 8% of second lubricant polytetrafluoroethylene, 15% of hygroscopic agent acetic acid and 3.5% of stabilizer dibasic lead phosphite into the A, and stirring for 8min at the rotating speed of 1000-2000r/min by using a pneumatic stirring gun;
C. and adding the B into a grinding machine, grinding for 50min at the rotating speed of 4500-. The paint color appearance was silvery, similar to the color of code 26380 in FED-STD-595, Federal color card, USA.
When the aluminum coating of the embodiment is applied, the steps are as follows:
a. after the parts are deoiled, sand blasting is carried out by using 120-mesh and 220-mesh corundum sand, and the parts are cleaned by using deionized water, dried and preheated, wherein the preheating temperature is 90 ℃.
b. Spraying the finished paint on the pretreated part, drying the surface of the coating, and curing at 180 ℃ for 65min to form the coating. The coating appeared golden yellow, approaching the color of code 33440 in FED-STD-595 Federal color chip.
The obtained self-lubricating aluminum coating is subjected to detection on appearance, thickness, adhesive force, fluid resistance, paint stripping resistance, brittleness, heat resistance, corrosion resistance and self-lubricating performance of the self-lubricating aluminum coating according to the specifications of EN4473 European standard (aerospace series-fastener colored aluminum coating-technical specification), NAS4006 American space navigation standard (aluminum coating) and Hi-Shear397 (self-lubricating aluminum coating of titanium alloy fastener system).
The appearance is visually inspected under natural scattered light or white transmitted light without reflected light, the illumination of the light is not lower than 300Lx (namely the illumination of equivalent parts under a 40W fluorescent lamp at a distance of 500 mm), and the coating is smooth, flat and uniform, is yellow and is close to the color of 33440 in FED-STD-595 Federal color card, and has no air holes, dark holes, air bubbles, nodules, pits or other uneven defects.
The thickness was measured by microscopy according to GJB 715.6 "thickness of Metal covering layer for fastener test method", and a measurement point was selected at a predetermined measurement site. The method comprises the following steps of randomly selecting 3 measuring points at the thread part of an internal thread fastener, selecting 3 points at the supporting surface part, selecting 2 points at the polished rod part of an external thread fastener, selecting 2 points at the thread part, selecting 2 points at the supporting surface, and enabling the coating thickness of all working surfaces of the external thread fastener to be 5-12.7 microns. The coating thickness of all working surfaces of the internal thread fastener is between 5 and 20 mu m. The remaining surface coating of the fastener should be completely covered. Bolt, screw working face: a head support surface, a stem, a thread; the working surface of the nut is as follows: bearing surfaces, threads.
And (4) adopting a drop hammer method (only suitable for the countersunk head bolt) to place the fastener on a static load pressure plate of a drop hammer testing machine to carry out a weight upsetting test. Flattening the head of the fastener or crushing the head of the fastener to the rod diameter, and inspecting the coating condition of the end face of the head under a magnifying lens of 4-6 times without separating the coating from the base metal. A tape method (only suitable for raised head bolts) is adopted, 3M 250 or the same type of tape is pasted on the rod part of the bolt (if the rod part of the bolt is too short, the tape can be pasted on the head part of the bolt), the tape is ensured to be in surface contact with the bolt, a roller with the weight of 1kg is used for rolling repeatedly once during pasting, the tape is pasted evenly and naturally, then the tape is violently torn off perpendicular to the pasting surface of the bolt, the condition of the coating is checked under a magnifying lens of 4-6 times, and the phenomenon that the coating is separated from the base metal does not occur.
And (3) fluid resistance, namely respectively putting RP-3 type aviation fuel oil meeting GB 6537 and YH-15 aviation hydraulic oil meeting GJB1177A into two test tubes, putting a fastener into each test tube, sealing, and storing for 30 days at the temperature of 65 +/-3 ℃. After the fastener is dried, an adhesion test is carried out by adopting a drop hammer method and an adhesive tape method, and the change condition of the hardness of the coating before and after the fastener is soaked is measured by a pencil method according to GB/T6739, so that the coating has no bubbles, and the phenomenon that the coating is separated from the base metal does not occur. The hardness of the coating was determined using the pencil method and the hardness of the coating was reduced by no more than 2 pencil hardness units for the soaked fastener compared to the un-soaked fastener.
And (3) paint stripping resistance, namely soaking the fastening piece in the MIL-R-81294 paint stripping agent, and keeping the fastening piece at the temperature of 25 +/-3 ℃ for 24 hours. The paint remover on the surface of the fastener was cleaned and dried with tap water, the fastener was visually inspected, and the adhesion test was performed by a drop hammer method or a tape method. And the change condition of the hardness of the coating before and after the fastener is soaked is measured by a pencil method according to GB/T6739, the coating has no bubbles, and the phenomenon that the coating is separated from the base metal does not occur. The hardness of the coating was determined using the pencil method and the hardness of the coating was not reduced by more than 2 pencil hardness units for the soaked fastener compared to the un-soaked fastener.
And (3) brittleness, installing 4 fasteners in a 7075-T6 aluminum alloy cushion block, wherein two fasteners are coated with aluminum, two fasteners are not coated with aluminum, the interference amount of the installation aperture is 0.05 mm-0.1 mm, the installation pretightening force is 80% of the rated load, and the fasteners are exposed for 72 hours at the temperature of 150 +/-5 ℃. And after cooling, taking down the fastener, respectively observing the aluminum-coated fastener under 200 times, and comparing the metallographic structure of the aluminum-coated fastener with that of the fastener which is not coated with aluminum, wherein no crack exists in the head fillet and the thread area. There was no significant difference in metallographic structure between the aluminium coated and non-aluminium coated fasteners.
And (3) heat resistance, placing 4 fasteners in an environment with the temperature of 235 +/-5 ℃ and preserving the heat for 4 hours. And then cooling to room temperature in the air, and performing an adhesion test by adopting a drop hammer method and an adhesive tape method, wherein the coating does not have bubbles or cracks and does not have the phenomenon of separation of the coating and the matrix metal.
The corrosion resistance is realized by adopting a method of an acetate spray test and an alternate immersion test, after the test, no obvious corrosion trace exists, and the corrosion degree of a test piece dimple part provided with the aluminum-coated fastener and the lower supporting surface of the fastener head does not exceed the corrosion degree of a corresponding area provided with the cadmium-plated fastener.
And (3) performing a press-in test (self-lubricating property), selecting 5 fasteners with the diameter of 6.35mm, and mounting the fasteners on a 2024-T4 board with the thickness of 12.7mm to ensure the interference between the bolt and the hole to be 0.08-0.12 mm. The mounting hole should be chamfered, the diameter after chamfering is 1.4mm larger than the hole diameter, and the chamfer edge can be rounded with 0.8 mm. And then slowly pressing the test piece into the mounting hole at the speed of 50 +/-6 mm/min until the under-head bearing surface of the bolt is contacted with the mounting plate, and recording the pressing force in the process, wherein the mounting hole and the bolt polished rod are not allowed to be obviously damaged, and the polished rod cannot expose out of the metal matrix.
Example 3
The preparation method of this example is as follows:
A. mixing 5% of aluminum powder, 40% of modified phenolic resin, 35% of butanone serving as an organic solvent and 1% of butyraldehyde serving as a binding agent, and stirring for 20-30min at the rotating speed of 1000-1500r/min by using a pneumatic stirring gun;
B. adding 2% of first lubricant molybdenum disulfide, 5% of second lubricant polytetrafluoroethylene, 10% of hygroscopic agent acetic acid and 2% of stabilizer dibasic lead phosphite into A, and stirring for 12min at the rotating speed of 1000-2000r/min by using a pneumatic stirring gun;
C. and adding the B into a grinding machine, grinding for 58min at the rotating speed of 4500-. The paint color appearance was silvery, similar to the color of code 26380 in FED-STD-595, Federal color card, USA.
When the novel chromium-free self-lubricating colored aluminum coating is applied, the method comprises the following steps:
a. after the parts are deoiled, sand blasting is carried out by using 120-mesh and 220-mesh corundum sand, and the parts are cleaned by using deionized water, dried and preheated, wherein the preheating temperature is 100 ℃.
b. Spraying the finished paint on the pretreated part, drying the surface of the coating, and curing at 200 ℃ for 55min to form the coating. The coating appeared golden yellow, approaching the color of code 33440 in FED-STD-595 Federal color chip.
The obtained self-lubricating aluminum coating is subjected to detection on appearance, thickness, adhesive force, fluid resistance, paint stripping resistance, brittleness, heat resistance, corrosion resistance and self-lubricating performance of the self-lubricating aluminum coating according to the specifications of EN4473 European standard (aerospace series-fastener colored aluminum coating-technical specification), NAS4006 American space navigation standard (aluminum coating) and Hi-Shear397 (self-lubricating aluminum coating of titanium alloy fastener system).
The appearance is visually inspected under natural scattered light or white transmitted light without reflected light, the illumination of the light is not lower than 300Lx (namely the illumination of equivalent parts under a 40W fluorescent lamp at a distance of 500 mm), and the coating is smooth, flat and uniform, is yellow and is close to the color of 33440 in FED-STD-595 Federal color card, and has no air holes, dark holes, air bubbles, nodules, pits or other uneven defects.
The thickness was measured by microscopy according to GJB 715.6 "thickness of Metal covering layer for fastener test method", and a measurement point was selected at a predetermined measurement site. The method comprises the following steps of randomly selecting 3 measuring points at the thread part of an internal thread fastener, selecting 3 points at the supporting surface part, selecting 2 points at the polished rod part of an external thread fastener, selecting 2 points at the thread part, selecting 2 points at the supporting surface, and enabling the coating thickness of all working surfaces of the external thread fastener to be 5-12.7 microns. The coating thickness of all working surfaces of the internal thread fastener is between 5 and 20 mu m. The remaining surface coating of the fastener is completely covered. Bolt, screw working face: a head support surface, a stem, a thread; the working surface of the nut is as follows: bearing surfaces, threads.
And (4) adopting a drop hammer method (only suitable for the countersunk head bolt) to place the fastener on a static load pressure plate of a drop hammer testing machine to carry out a weight upsetting test. Flattening the head of the fastener or crushing the head of the fastener to the rod diameter, and inspecting the coating condition of the end face of the head under a magnifying lens of 4-6 times without separating the coating from the base metal. A tape method (only suitable for raised head bolts) is adopted, 3M 250 or the same type of tape is pasted on the rod part of the bolt (if the rod part of the bolt is too short, the tape can be pasted on the head part of the bolt), the tape is ensured to be in surface contact with the bolt, a roller with the weight of 1kg is used for rolling repeatedly once during pasting, the tape is pasted evenly and naturally, then the tape is violently torn off perpendicular to the pasting surface of the bolt, the condition of the coating is checked under a magnifying lens of 4-6 times, and the phenomenon that the coating is separated from the base metal does not occur.
And (3) fluid resistance, namely respectively putting RP-3 type aviation fuel oil meeting GB 6537 and YH-15 aviation hydraulic oil meeting GJB1177A into two test tubes, putting a fastener into each test tube, sealing, and storing for 30 days at the temperature of 65 +/-3 ℃. After the fastener is dried, an adhesion test is carried out by adopting a drop hammer method and an adhesive tape method, and the change condition of the hardness of the coating before and after the fastener is soaked is measured by a pencil method according to GB/T6739, so that the coating has no bubbles, and the phenomenon that the coating is separated from the base metal does not occur. The hardness of the coating was determined using the pencil method and the hardness of the coating was not reduced by more than 2 pencil hardness units for the soaked fastener compared to the un-soaked fastener.
And (3) paint stripping resistance, namely soaking the fastening piece in the MIL-R-81294 paint stripping agent, and keeping the fastening piece at the temperature of 25 +/-3 ℃ for 24 hours. The paint remover on the surface of the fastener was cleaned and dried with tap water, the fastener was visually inspected, and the adhesion test was performed by a drop hammer method or a tape method. And the change condition of the hardness of the coating before and after the fastener is soaked is measured by a pencil method according to GB/T6739, the coating has no bubbles, and the phenomenon that the coating is separated from the base metal does not occur. The hardness of the coating was determined using the pencil method and the hardness of the coating was reduced by no more than 2 pencil hardness units for the soaked fastener compared to the un-soaked fastener.
And (3) brittleness, installing 4 fasteners in a 7075-T6 aluminum alloy cushion block, wherein two fasteners are coated with aluminum, two fasteners are not coated with aluminum, the interference amount of the installation aperture is 0.05 mm-0.1 mm, the installation pretightening force is 80% of the rated load, and the fasteners are exposed for 72 hours at the temperature of 150 +/-5 ℃. And after cooling, taking down the fastener, respectively observing the aluminum-coated fastener under 200 times, and comparing the metallographic structure of the aluminum-coated fastener with that of the fastener which is not coated with aluminum, wherein no crack exists in the head fillet and the thread area. There was no significant difference in metallographic structure between the aluminium coated and non-aluminium coated fasteners.
And (3) heat resistance, placing 4 fasteners in an environment with the temperature of 235 +/-5 ℃ and preserving the heat for 4 hours. And then cooling to room temperature in the air, and performing an adhesion test by adopting a drop hammer method and an adhesive tape method, wherein the coating does not have bubbles or cracks and does not have the phenomenon of separation of the coating and the matrix metal.
The corrosion resistance is realized by adopting a method of an acetate spray test and an alternate immersion test, no obvious corrosion mark is generated after the test, and the corrosion degree of a test piece dimple part provided with the aluminum-coated fastener and the corrosion degree of a lower supporting surface of a fastener head do not exceed the corresponding area provided with the cadmium-coated fastener.
And (3) performing a press-in test (self-lubricating property), selecting 5 fasteners with the diameter of 6.35mm, and mounting the fasteners on a 2024-T4 board with the thickness of 12.7mm to ensure the interference between the bolt and the hole to be 0.08-0.12 mm. The mounting hole should be chamfered, the diameter after chamfering is 1.4mm larger than the hole diameter, and the chamfer edge can be rounded with 0.8 mm. And then slowly pressing the test piece into the mounting hole at the speed of 50 +/-6 mm/min until the under-head bearing surface of the bolt is contacted with the mounting plate, and recording the pressing force in the process, wherein the mounting hole and the bolt polished rod are not allowed to be obviously damaged, and the polished rod cannot expose out of the metal matrix.
The self-lubricating colored aluminum coating is not only suitable for coating titanium alloy fasteners, but also suitable for coating other materials such as stainless steel, nickel-based alloy and the like which need to be connected with different metal material structures, composite material structures and metal and composite material structures.
While the invention has been described with reference to the above embodiments, the scope of the invention is not limited thereto, and the above components may be replaced with similar or equivalent elements known to those skilled in the art without departing from the spirit of the invention.
Claims (10)
1. The novel chromium-free self-lubricating coloring aluminum coating for aviation is characterized in that: calculated by taking the total mass of the self-lubricating aluminum coating as 100 percent, the formula of the aluminum coating comprises the following components in percentage by mass:
modified phenolic resin: 20 to 40 percent of
A first lubricant: 2 to 5 percent
A second lubricant: 5-10 percent
Moisture absorbent: 10 to 20 percent
Aluminum powder: 5-10 percent
A stabilizer: 2 to 5 percent
Binding agent: 1 to 1.5 percent
Organic solvent: and (4) the balance.
2. The novel chromium-free self-lubricating colored aluminum paint for aviation according to claim 1, wherein: the first lubricant is molybdenum disulfide.
3. The novel chromium-free self-lubricating colored aluminum paint for aviation according to claim 1, wherein: the second lubricant is polytetrafluoroethylene.
4. The novel chromium-free self-lubricating colored aluminum paint for aviation according to claim 1, wherein: the hygroscopic agent is acetic acid.
5. The novel chromium-free self-lubricating colored aluminum paint for aviation according to claim 1, wherein: the aluminum powder is aluminum powder with fineness of less than 4 mu m.
6. The novel chromium-free self-lubricating colored aluminum paint for aviation according to claim 1, wherein: the stabilizer is dibasic lead phosphite.
7. The novel chromium-free self-lubricating colored aluminum paint for aviation according to claim 1, wherein: the binding agent is butyraldehyde.
8. The novel chromium-free self-lubricating colored aluminum paint for aviation according to claim 1, wherein: the organic solvent is butanone.
9. A method for preparing a novel chromium-free self-lubricating colored aluminum paint for aviation according to any one of claims 1 to 8, which is characterized by comprising the following steps:
A. mixing the aluminum powder, the modified phenolic resin, the organic solvent and the bonding agent in parts, and stirring for 20-30min at the rotating speed of 1000-1500r/min by using a pneumatic stirring gun;
B. adding the first lubricant, the second lubricant, the moisture absorbent and the stabilizer into the A, and stirring for 8-12min at the rotating speed of 1000-2000r/min by using a pneumatic stirring gun;
C. adding B into a grinder, grinding for 50-58min at the rotating speed of 4500-.
10. Use of a novel chromium-free self-lubricating colored aluminum paint for aviation according to any one of claims 1 to 8, characterized by the steps of:
a. after the parts are deoiled, blasting sand by using 120-mesh and 220-mesh corundum sand, cleaning by using deionized water, drying and preheating, wherein the preheating temperature is 95 +/-5 ℃;
b. spraying the finished aluminum paint on the pretreated part, drying the surface of the coating, and curing at 190 +/-10 ℃ for 55-65min to form the coating.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010340981.XA CN111548700A (en) | 2020-04-26 | 2020-04-26 | Novel chromium-free self-lubricating coloring aluminum coating for aviation and preparation method and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010340981.XA CN111548700A (en) | 2020-04-26 | 2020-04-26 | Novel chromium-free self-lubricating coloring aluminum coating for aviation and preparation method and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111548700A true CN111548700A (en) | 2020-08-18 |
Family
ID=72005923
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010340981.XA Pending CN111548700A (en) | 2020-04-26 | 2020-04-26 | Novel chromium-free self-lubricating coloring aluminum coating for aviation and preparation method and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111548700A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117384518A (en) * | 2023-12-11 | 2024-01-12 | 东方蓝天钛金科技有限公司 | Coating for stabilizing pretightening force of self-locking nut and coating process thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101760091A (en) * | 2009-12-14 | 2010-06-30 | 上海维凯化学品有限公司 | Single-coating type matt transferring aluminum-plating paint and preparation method thereof |
| CN102766382A (en) * | 2012-08-09 | 2012-11-07 | 广州慧谷化学有限公司 | Hollow alkali washing aluminum aqueous protective paint and preparation method and application thereof |
| CN103952056A (en) * | 2014-05-21 | 2014-07-30 | 航天材料及工艺研究所 | High-temperature-resistant lubricating anticorrosive aluminum paint and preparation method thereof |
| CN106147564A (en) * | 2015-04-05 | 2016-11-23 | 泉州市合创涂料科技有限公司 | A kind of preparation method of Chrome-free anticorrosive paint |
| CN106995891A (en) * | 2017-05-18 | 2017-08-01 | 含山瑞可金属有限公司 | A kind of anti-corrosion and high strength titanium alloy fastener |
-
2020
- 2020-04-26 CN CN202010340981.XA patent/CN111548700A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101760091A (en) * | 2009-12-14 | 2010-06-30 | 上海维凯化学品有限公司 | Single-coating type matt transferring aluminum-plating paint and preparation method thereof |
| CN102766382A (en) * | 2012-08-09 | 2012-11-07 | 广州慧谷化学有限公司 | Hollow alkali washing aluminum aqueous protective paint and preparation method and application thereof |
| CN103952056A (en) * | 2014-05-21 | 2014-07-30 | 航天材料及工艺研究所 | High-temperature-resistant lubricating anticorrosive aluminum paint and preparation method thereof |
| CN106147564A (en) * | 2015-04-05 | 2016-11-23 | 泉州市合创涂料科技有限公司 | A kind of preparation method of Chrome-free anticorrosive paint |
| CN106995891A (en) * | 2017-05-18 | 2017-08-01 | 含山瑞可金属有限公司 | A kind of anti-corrosion and high strength titanium alloy fastener |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117384518A (en) * | 2023-12-11 | 2024-01-12 | 东方蓝天钛金科技有限公司 | Coating for stabilizing pretightening force of self-locking nut and coating process thereof |
| CN117384518B (en) * | 2023-12-11 | 2024-02-06 | 东方蓝天钛金科技有限公司 | Coating for stabilizing pretightening force of self-locking nut and coating process thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH101787A (en) | Coating mixture and coating | |
| US11261135B2 (en) | Chromate-free ceramic compositions with reduced curing temperature | |
| CN114318323A (en) | Method for repairing local damage of aircraft skin surface in situ through cold spraying | |
| EA034055B1 (en) | Threaded connection for pipe or tube and method for producing the threaded connection for pipe or tube | |
| US20200148894A1 (en) | Graphene based corrosion-resistant coating | |
| CN103952056A (en) | High-temperature-resistant lubricating anticorrosive aluminum paint and preparation method thereof | |
| CN111548700A (en) | Novel chromium-free self-lubricating coloring aluminum coating for aviation and preparation method and application thereof | |
| EP2354470B1 (en) | Methods for inhibiting corrosion of high strength steel turbine components | |
| JP2014518331A (en) | Multi-layer coating system for protecting superalloy substrates from heat and corrosion | |
| CN112718423A (en) | Anticorrosive coating method for wind generating set | |
| CN1059224C (en) | Corrosionproof lubricant coating based on molybdenum disulfide | |
| CN103527807B (en) | Ceramic composite coating type anticorrosion valve and ceramic composite coating thereof the coating processes in anticorrosion valve | |
| CN102965707B (en) | A kind of method of solid lubricant film with molybdenum bisuphide fluid lubricant electricity | |
| CN113522695A (en) | Corrosion-resistant lubricating composite coating for fastener and preparation method thereof | |
| CN102965179B (en) | Molybdenum disulfide liquid lubricant and preparation method thereof | |
| Holubka et al. | Durability of adhesive bonds to zinc-coated steels: effects of corrosive environments on lap shear strength | |
| CN1218099A (en) | High temperature anti-sticky Lubricant coating material | |
| CN111979535A (en) | Cold spraying remanufacturing process for outer cylinder surface of undercarriage | |
| Holmes et al. | The substitution of IVD aluminum for cadmium | |
| CN113969099A (en) | Water-based zinc-aluminum coating and production process thereof | |
| CN113953165A (en) | Spraying process of inorganic aluminum anticorrosive coating of compressor blade disc repair part and compressor blade disc | |
| CN117920555A (en) | Comprehensive anti-corrosion treatment method for fastener in marine atmospheric environment | |
| Butler et al. | Aero engine‐finishes | |
| CN114602779A (en) | Anticorrosive spraying process for threaded fastener | |
| CN102133571B (en) | Method for preparing chloride ion corrosion resistant bar material with nano composite coating |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information |
Address after: No.68, Jiahu Road, fuchengao community, Pinghu street, Longgang District, Shenzhen City, Guangdong Province Applicant after: Shenzhen Asia Pacific Aviation Technology Co.,Ltd. Address before: No.68, Jiahu Road, fuchengao community, Pinghu street, Longgang District, Shenzhen City, Guangdong Province Applicant before: SHENZHEN ASIA-PACIFIC AVIATION TECHNOLOGY Co.,Ltd. |
|
| CB02 | Change of applicant information |