CN1303259C - Molybdenum disulfide and nickel phosphorus composite deposition liquid and its electrodeposition method - Google Patents

Abstract

The present invention discloses molybdenum disulfide and nickel phosphorus compounding deposition liquid used for processing micro-mechanical friction surfaces. The deposition liquid comprises soluble molybdate tetrasulfide, soluble nickel salts, phosphoric soluble oxysalts and water, wherein the molar ratio of the soluble molybdate tetrasulfide to the soluble nickel salts is 0.01 to 0.5:1, the molar ratio of the phosphoric soluble oxysalts to the soluble nickel salts is 0.01 to 30:1, and the molar ratio of the soluble nickel salts to the water is 1 to 100:5000. The present invention also discloses an electrodeposition method for treating the surfaces of mechanical members with the compounding deposition liquid. The method comprises: a surface is cleaned and is put in an electrolytic tank filled with the compounding deposition liquid, a mechanical member is connected with a cathode of a power supply, the power supply is switched on for electrodeposition for 1 to 120 minutes with the current density of 0.1 to 100 mA per square centimeter of areas to be treated at room temperature, and finally, the mechanical member is taken out, washed, dried and is in heat preservation in a protective atmosphere.

Description

Molybdenum disulfide and nickel-phosphorus composite deposition solution and electrodeposition method thereof

Technical field

The invention relates to a surface treatment solution for mechanical parts and a treatment method thereof, in particular to a molybdenum disulfide and nickel-phosphorus composite deposition solution and an electrodeposition method for treating micromechanical friction surfaces.

Background technique

Molybdenum disulfide has a layered structure, and the layers are combined by van der Waals force. Molecules can easily slide along these planes, and the shear force is small. Due to the existence of lattice defects in the actual crystal, the shear force is further reduced and has excellent anti-friction performance, so it has been widely used in the field of friction.

The nickel-phosphorus coating can improve the wear resistance of the friction surface due to its high hardness after heat treatment, and can be used to strengthen the friction surface.

In general, molybdenum disulfide and nickel-phosphorus composite films use the method of directly adding original molybdenum disulfide particles into the solution, and its size is limited by the size of the original particles. The molybdenum disulfide particles generated by the method are far smaller than the MoS ₂ particle size in the composite film prepared by other processes, and the distribution is more uniform, thereby improving the anti-friction and wear resistance of the surface of mechanical parts.

In addition, molybdenum disulfide and nickel-phosphorus composite films are generally only suitable for macroscopic friction workpiece surfaces, and this composite film is not only applied to macroscopic friction workpiece surfaces, but also can be applied to the surface of micro-mechanical friction components.

MEMS is a multi-disciplinary emerging discipline developed on the basis of microelectronics technology. It relies on microelectronics and mechanical processing technology, and its scope involves microelectronics, mechanics, mechanics, automatic control, material science, etc. A variety of engineering techniques and disciplines. However, due to the strong adhesive wear caused by the homogeneous friction between the friction pairs of the micromachines, and the stability of the movable micromachines is extremely sensitive to slight wear, the micromachines often fail due to wear in a short period of time. Surface microscopic friction has become a bottleneck in the development of micromachines. The molybdenum disulfide and nickel-phosphorus composite film combines the advantages of the two components to further improve its anti-friction and wear resistance properties.

Using a new electrodeposition method to deposit molybdenum disulfide and nickel-phosphorus composite film, it is closely combined with the micro-mechanical manufacturing process. Making the molybdenum disulfide and nickel-phosphorus composite film easy to deposit on the micro-mechanical friction surface is an effective way to achieve a real breakthrough in the micro-mechanical friction problem. The composite deposition of molybdenum disulfide and nickel-phosphorus composite film technology is applied to micro-mechanical friction surfaces, and there is no public report at home and abroad.

Contents of Invention

The invention provides a molybdenum disulfide and nickel-phosphorus composite deposition solution and an electrodeposition method capable of improving the friction-reducing and wear-resistant properties of the surface of mechanical parts. The invention is especially suitable for use on micro-mechanical friction surfaces.

The present invention adopts following technical scheme:

The molybdenum disulfide and nickel-phosphorus composite deposition solution of the present invention includes soluble tetrathiomolybdate, soluble nickel salt, soluble oxysalt of phosphorus and water, soluble tetrathiomolybdate and soluble nickel salt The molar ratio of the soluble nickel salt to water is 0.01 to 0.5:1, the molar ratio of the soluble oxygen acid salt of phosphorus to the soluble nickel salt is 0.01 to 30:1, and the molar ratio of the soluble nickel salt to water is 1 to 100:5000.

The electro-deposition method for surface treatment of mechanical parts by the composite deposition solution of the present invention is as follows: firstly, the surface to be treated of the mechanical parts is cleaned, and then the surface to be treated of the mechanical parts is placed in an electrolytic cell storing the above-mentioned composite deposition solution , and connect the mechanical parts to be treated with the cathode of the power supply, at room temperature, with a current density of 0.1 milliampere-100 milliamperes per square centimeter to be treated, switch on the power supply for 1-120 minutes, and an electrochemical reaction occurs , so that the molybdenum disulfide and nickel-phosphorus composite film is deposited on the surface of the mechanical parts to be treated. Finally, the mechanical parts to be treated are taken out, cleaned, dried, and kept in a protective atmosphere at 100°C-900°C for 0.5-4 hours. hours, a homogeneous molybdenum disulfide and nickel-phosphorus composite film with a thickness of 10 nanometers to 500 microns can be obtained.

Compared with prior art, the present invention has following advantage:

(1) because nickel ion and hypophosphite are reduced to nickel-phosphorus layer at cathode, and tetrathiomolybdate is reduced to molybdenum disulfide and nickel-phosphorus layer deposition together at cathode, make composite deposition solution of the present invention can be in Molybdenum disulfide and nickel-phosphorus composite films are formed on the surface of the part, and molybdenum disulfide has a layered structure, and the layers are combined by Van der Waals force, and the molecules can easily slide along these planes with small shear force. Due to the presence of lattice defects in the actual crystal, the shear force is further reduced and has excellent anti-friction performance. The nickel-phosphorus coating can improve the wear resistance of the friction surface due to its high hardness after heat treatment. The present invention combines molybdenum disulfide and Nickel-phosphorus is compounded together to form a composite film, thereby improving the anti-friction and wear-resisting properties of the surface of the mechanical part; especially the nano-scale molybdenum disulfide and nickel-phosphorus composite film can be formed on the surface of the part provided by the present invention, so that the present invention can be combined with The combination of MEMS manufacturing process is suitable for micro-mechanical use.

(2) The electrodeposition method of the present invention is not only applied to the micromechanical surface, but also can be applied to the macroscopic mechanical friction surface. The molybdenum disulfide particles generated by the electrochemical method in the present invention are nanoscale, which improves the reduction of the composite film. friction and wear resistance.

(3) The film thickness of the electrodeposited molybdenum disulfide and nickel-phosphorus composite film can vary from nanometer to micron level. The molybdenum disulfide particles are fine and the film surface is smooth. Facilitates the dimensional requirements of the micromechanical surface modification layer.

(4) The molybdenum disulfide and nickel-phosphorus composite deposition method is used to give full play to the advantages of the two materials, which can significantly improve the anti-friction and wear-resisting properties of the workpiece surface.

(5) The presence of additives stabilizes the solution, changes the deposition rate and improves the quality of molybdenum disulfide and nickel-phosphorus composite films.

Detailed ways

Example 1

A molybdenum disulfide and nickel-phosphorus composite deposition solution for surface treatment of mechanical parts, including soluble tetrathiomolybdate, soluble nickel salt, soluble oxysalt of phosphorus and water, soluble oxyacid of phosphorus Salt can be sodium pyrophosphate, and simultaneously, sodium pyrophosphate has also played the effect of complexing agent, and the mol ratio of above-mentioned soluble tetrathiomolybdate and soluble nickel salt is 0.01～0.5: 1, and present embodiment can select: 0.03 : 1, 0.1: 1, 0.21: 1, and 0.3: 1; the molar ratio of sodium pyrophosphate to soluble nickel salt is 0.01 to 10: 1, and this embodiment can be selected: 0.2: 1, 0.5: 1, 4: 1 and 7: 1; present embodiment also can comprise additive, and this additive comprises at least a kind of organic acid or salt, and this additive and soluble nickel salt molar ratio are 1～6: 1, and its effect is to keep the effect of solution stability, improves deposition The effect of speed and deposit performance, present embodiment can be selected: 1.3: 1, 1.9: 1, 2: 1, 3.5: 1, 4.4: 1 and 5.8: 1, and above-mentioned additive can be trisodium citrate, chloride A combination of one or more of ammonium, disodium edetate, lactic acid, etc., and the ratio of its components can be any ratio; the molar ratio of soluble nickel salt to water is 1-100:5000, this Example options: 20:5000, 37:5000, 55:5000, 67:5000, 79:5000 and 90:5000. The above-mentioned soluble oxysalts of phosphorus provide phosphorus elements in the solution for the nickel-phosphorus layer deposition process, and part of the soluble oxysalts of phosphorus prevents the solution from turbid precipitation and maintains the stability of the solution.

Example 2

A molybdenum disulfide and nickel-phosphorus composite deposition solution for surface treatment of mechanical parts, composed of soluble tetrathiomolybdate, soluble nickel salt, sodium pyrophosphate and additives, the molar percentage of its active ingredients (excluding water) It is 1%～20% of soluble tetrathiomolybdate, and 2%, 7%, 11%, 16% and 19% can be selected in this embodiment; 25%～50% of soluble nickel salt, can be selected in this embodiment: 27 %, 29%, 33%, 40% and 47%; sodium hypophosphite 25% ~ 60%, the present embodiment can choose 28%, 31%, 35%, 36% and 55%; sodium pyrophosphate 25% ~ 60% %, optional in this embodiment: 26%, 31%, 34%, 37% and 55%; disodium edetate 1% to 20%, optional in this embodiment: 3%, 9%, 14% , 17% and 19%; trisodium citrate 1～30%, the present embodiment can select: 3%, 7%, 17%, 25%, 28%. The molar percentage of water in the electrodeposition solution is 99% to 30%, which can be selected in this embodiment: 35%, 45%, 52%, 60%, 71% and 80%.

Example 3

A kind of electrodeposition method that utilizes above-mentioned composite deposition liquid to carry out surface treatment to mechanical parts is: firstly carry out cleaning treatment to the surface to be treated of mechanical parts, and this cleaning treatment includes degreasing, degreasing, ash removal and insulating layer removal etc., and then Place the surface of the mechanical parts to be treated in the electrolytic tank storing the above-mentioned composite deposition solution, and connect the mechanical parts to be treated with the cathode of the power supply. The current density is 1-120 minutes when the power is turned on, and the electrochemical reaction occurs. For example, the time of electrodeposition when the power is turned on can be: 1, 120, 111, 74, 32, 56 or 15 minutes to make molybdenum disulfide Electrodeposit the nickel-phosphorus composite film on the surface of the mechanical parts to be treated. Finally, take out the mechanical parts to be processed, clean them, dry them, and keep them warm for 0.5 to 4 hours in a protective atmosphere at 100°C-900°C, for example: At room temperature, with a current density of 50mA per square centimeter to be treated, turn on the power supply for 30 minutes, and an electrochemical reaction occurs. Finally, take out the mechanical parts to be treated, clean them, dry them, and place them in a protective atmosphere for 400 ℃ for 1 hour to obtain a homogeneous molybdenum disulfide and nickel-phosphorus composite film with a thickness of 5 microns.

Example 4

The molybdenum disulfide and nickel-phosphorus composite deposition solution of the present invention is used to process single-sided polished single-crystal silicon wafers for micromachines. The diameter of the wafer is 3 inches, the crystal orientation is <110>, doped with As, and the resistivity is 0.002 ohm cm. The composition of molybdenum disulfide and the low-temperature electrodeposition process are as follows:

The composition of molybdenum disulfide and nickel phosphorus electrodeposition solution is that the molar ratio of soluble tetrathiomolybdate to soluble nickel salt is 0.05, the molar ratio of sodium hypophosphite to soluble nickel salt is 2, sodium pyrophosphate and soluble nickel salt The molar ratio of the soluble nickel salt to water is 1.5:1, and the molar ratio of the soluble nickel salt to water is 1-100:5000.

Composite electrodeposition process

1. Prepare molybdenum disulfide and nickel-phosphorus composite electrodeposition solution in proportion and place it in the electrolytic cell;

2. Degrease, degrease, ash and deoxygenate the surface of the silicon wafer;

3. Place the silicon wafer in the electrodeposition tank, connect it to the cathode of the power supply, connect the platinum electrode to the anode of the power supply and put it into the electrolytic tank; the electrolyte is at room temperature.

4. Set the current area according to the area of the silicon wafer, and turn on the power for electrodeposition for 10 minutes.

5. Take out the substrate, wash it, dry it, and keep it warm for 1 hour under the condition of 100°C-900°C in _N2 atmosphere. That is, a homogeneous molybdenum disulfide and nickel-phosphorus composite lubricating film with a thickness of 300 nanometers was obtained.

Example 5

Cr12 die steel is treated with the formula of molybdenum disulfide and nickel-phosphorus composite deposition solution of the present invention. The composition and low-temperature electrodeposition process of molybdenum disulfide and nickel-phosphorus composite deposition solution are as follows:

The composition of molybdenum disulfide and nickel phosphorus electrodeposition is, the composition of molybdenum disulfide and nickel phosphorus electrodeposition solution is, the molar ratio of soluble tetrathiomolybdate and soluble nickel salt is 0.05:1, sodium pyrophosphate and soluble nickel The molar ratio of salt is 1:1, the molar ratio of trisodium citrate to soluble nickel salt is 1:1, and the molar ratio of soluble nickel salt to water is 1-100:5000.

Electrodeposition process

1. Prepare molybdenum disulfide and nickel-phosphorus composite electrodeposition solution in proportion and place it in the electrolytic cell;

2. Degrease, degrease, and derust the surface of Cr12 mold steel;

3. Place the Cr12 mold steel in the electrodeposition tank, connect it to the cathode of the power supply, connect the platinum electrode to the anode of the power supply and put it into the electrolytic tank; the electrolyte is at normal temperature;

4. Set the current area according to the area of Cr12 mold steel, and turn on the power for electrodeposition for 30 minutes.

5. Take out the substrate, wash it, dry it, and keep it warm for 1 hour under the condition of 100°C-900°C in _N2 atmosphere. That is, a homogeneous molybdenum disulfide and nickel-phosphorus lubricating film with a thickness of 18 microns was obtained.

Claims (3)

1, a kind of molybdenumdisulphide and nickel phosphorus composite deposition liquid that is used for the machinery part surface processing, it is characterized in that comprising the solvable oxysalt and the water of solubility tetrathiomolybdate, soluble nickel salt, phosphorus, the mol ratio of solubility tetrathiomolybdate and soluble nickel salt is 0.01～0.5: 1, the solvable oxysalt of phosphorus and the mol ratio of soluble nickel salt are 0.01～30: 1, and the mol ratio of soluble nickel salt and water is 1～100: 5000.

2, molybdenumdisulphide according to claim 1 and nickel phosphorus composite deposition liquid is characterized in that comprising additive, and this additive comprises a kind of organic acid or salt at least, and the mol ratio of this additive and soluble nickel salt is 1～6.

3; a kind of described composite deposition liquid of claim 1 that utilizes carries out the surface-treated electro-deposition method to mechanical component; it is characterized in that earlier cleaning being carried out on the pending surface of mechanical component handles; pending surface with mechanical component places the electrolyzer that contains above-mentioned composite deposition liquid again; and pending mechanical component are connected with power cathode; at room temperature; current density with 0.1 milliampere-100 milliamperes of every square centimeter of pending areas; connect power supply galvanic deposit 1-120 minute; electrochemical reaction takes place; make molybdenumdisulphide and the galvanic deposit of nickel phosphorus composite membrane in the surface of pending mechanical component; at last; take out pending mechanical component, and to its cleaning, drying; in protective atmosphere, be incubated 0.5～4 hour under 100 degree-900 degree conditions, promptly obtain the homogeneous molybdenumdisulphide and the nickel phosphorus composite membrane of 10 nanometers-500 micron thickness.