KR20160054906A - Hybrid type low friction materials mixed plating layer and dimple and automotive engine with the same - Google Patents

Abstract

The present invention relates to a plating and dimple mixed hybrid type low friction material, and a vehicle engine comprising the same. A plating layer having an excellent low-friction characteristic is formed by an electroplating method, and a low-friction dimple pattern is complexly formed in an area where the plating layer is formed in order to maximize a low-friction effect. Therefore, the present invention comprises: a base material; the plating layer formed by the electroplating method on a surface of the base material to reduce friction generated by surface contact; and a plurality of dimples formed on the plating layer to significantly reduce the friction generated by the surface contact.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a hybrid type low friction member having a combination of a plating and a dimple, and an automobile engine having the hybrid type low friction member,

The present invention relates to a low-friction member for an automobile engine. More particularly, the present invention relates to a low-friction member for an automobile engine, in which a plating layer having excellent low friction characteristics is first formed by electroplating and then a low friction dimple pattern is formed in a multi- The present invention relates to a hybrid type low friction member having a combination of a plating and a dimple.

In the automobile industry, the friction characteristics of many engine parts are very important for energy saving, maintenance cost, cost reduction due to parts exchange and breakage, reduction of investment cost by extending life, and energy saving by reducing friction. In particular, wear and friction behavior in the frictional properties have a considerable influence on the surface morphology in contact with each other. In the case of sliding contact in the lubricated state, the frictional characteristic can be improved by the formation of surface irregularities such as a dimple shape. These irregularities serve to prevent the lubricant reservoir and lubricant from leaking out. In addition, the abrasive particles can be removed from the contact surface and can be collected inside the structure, thereby preventing further wear from being caused by abrasive particles.

Therefore, in recent years, various studies have been conducted to reduce fuel consumption and energy loss due to friction in power machine parts by reducing energy loss due to frictional resistance of engine parts. Among these methods, Research is actively underway.

Surface texturing technology refers to machining multiple dimples or grooves on at least one surface of two surfaces in order to improve the lubrication characteristics between two surfaces that perform relative motion through a lubricant. Surface irregularities promote wear particle trapping, lubricant storage, and hydrodynamic pressure generation.

In particular, laser surface texturing is mainly used to make patterns in the form of dimples. When compared with other texturing methods, the processing time is extremely fast and the shape and size of the dimples can be controlled by using laser parameters (pulse energy, pulse number) Looking at the research trends in surface texturing, Germany S. Schreck et Nd: texturing of the channel and form dimples for 100Cr ₆ steel and Al ₂ O ₃ by using a YAG laser, and that the friction reduction in accordance with the density under lubrication And Izhak Etsion of Israel experimentally confirmed that the partial pattern was improved over the entire patterning by using laser surface texturing in the cylinder ring which is the direct contact with the cylinder of the internal combustion engine. In addition, Kovalchenko of the Argonne Institute in the USA found that the wear rate of the balls was high when the dimples were based on the dimple density using Laser Surface Texturing (LST), the friction coefficient according to the viscosity of the lubricant and the wear scar of the ball, The contact area increased and the transition from boundary lubrication to the mixed lubrication region occurs rapidly in the lubricated state, suggesting that the friction coefficient decreases.

However, even in the above-mentioned study, it is urgent to develop a new type of low friction member which improves the low friction effect due to insufficient low friction effect through the laser surface texturing technique.

Korean Published Patent Application No. 2014-0088299 (Apr.

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems of the prior art as described above, and it is an object of the present invention to provide a method of manufacturing an electro- The present invention also provides a hybrid type low friction member in which a dimple pattern is combined with a plating and a dimple to maximize a low friction effect, and an automobile engine having the hybrid type low friction member.

To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a hybrid type low friction member comprising: a base material; A plating layer formed on the surface of the base material by electroplating to reduce friction caused by surface contact; And a plurality of dimples formed on the plating layer so as to further reduce friction caused by surface contact.

Here, the dimples may be formed in a region where the plating layer is formed after the plating layer is formed.

The dimples may be formed to a depth not exceeding the thickness of the plating layer.

The thickness of the plating layer may be 1.0 mm or less.

The plating layer may be Ni-SiC.

In addition, ultrasonic waves may be applied to the electrolyte solution during electroplating for forming the plating layer.

Also, the ultrasonic wave may be applied in a frequency range of 30 to 58 kHz within a power range of 150 to 250 W.

The electroplating may be pulse electroplating to apply a pulse current.

Further, the plating layer may be made of Ni material.

The diameter of the dimples may be in the range of 10 to 400 mu m.

Also, the interval between adjacent dimples may be in the range of 120 to 180 mu m.

The depth of the dimple may be in the range of 0.5 to 1.5 times the diameter of the dimple.

The dimples may be formed by laser irradiation.

Further, the dimples may be characterized in that spherical solid lubricant particles are accommodated to have bearing characteristics.

Further, the surface of the solid lubricant particles may be provided with a plurality of fine oil pockets for receiving a liquid lubricant.

Further, the surface of the solid lubricant particle may be characterized by being coated with a liquid lubricant.

The inlet width of the dimples is formed to be narrower than the maximum diameter of the solid lubricant particles to prevent the solid lubricant particles from escaping.

The hybrid type low friction member and the automobile engine having the composite of the plating and the dimple according to the present invention have a new type of low friction in which the low friction characteristics of the plating layer and the dimple formed by the electroplating act together, Member can be realized.

Further, the present invention achieves more excellent low friction characteristics by applying Ni-SiC as a material of the plating layer by electroplating.

Further, the present invention achieves better low friction characteristics by applying ultrasonic waves in electroplating.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view for explaining an inspired technical concept of a hybrid type low friction member according to an embodiment of the present invention; FIG.
2 is a longitudinal sectional view for explaining a configuration of a hybrid type low friction member in which a plating and a dimple are combined according to an embodiment of the present invention
FIGS. 3A to 3D are a series of ref- erence drawings for explaining a method of manufacturing a hybrid type low-friction member in which plating and dimples are combined according to an embodiment of the present invention
Fig. 4 is a photograph showing the surface morphology of the Ni-SiC plated layer depending on the current type used in electroplating and whether or not the ultrasonic wave is applied.
Fig. 5 is a graph comparing the Vickers microhardness of each ultrasonic wave by frequency in electroplating
6 is a graph comparing the Vickers microhardness of each ultrasonic wave by electric power applied during electroplating
FIG. 7 is a graph comparing the Vickers microhardness according to the current type and the presence or absence of ultrasonic waves during electroplating
8 is an X-ray diffraction analysis graph for examining the peak intensity according to the material used in electroplating and the application of ultrasonic waves
FIG. 9 is a graph showing the cross-sectional shape of the plating layer according to the current type and the application of ultrasonic waves during electroplating
10 is a graph showing a comparative analysis of the Vickers microhardness and the crystal grain size of Ni according to the current type and the application of ultrasonic waves during electroplating
Fig. 11 is a photograph and graph showing comparative analysis of wear and friction coefficient according to current type and ultrasonic wave application in electroplating
FIG. 12 is a graph showing the electrochemical corrosion degree measured by the current type and the presence or absence of ultrasonic waves during electroplating
13 is a photograph of the surface of the comparative objects having different intervals of dimples adjacent to the Ni-SiC plating layer formed by electroplating
14 is a graph showing the friction coefficient of comparative objects having different dimples of the neighboring Ni-SiC plated layer formed by electroplating
Fig. 15 is a photograph of a wear track of a comparative object in which the interval of dimples adjacent to the Ni-SiC plated layer formed by electroplating is different
16 is an optical microscope 3D photograph of the abrasion track of the comparative objects with different intervals of the dimples adjacent to the Ni-SiC plated layer formed by the electroplating
FIG. 17 is a photograph showing a wear area of a counter ball frictionally contacted with a comparative object having dimples of a neighboring Ni-SiC plating layer formed by electroplating
18 is an optical microscope 3D photograph showing a wear region of a counter ball frictionally contacted with a comparative object having a dimple interval adjacent to a Ni-SiC plating layer formed by electroplating
FIG. 19 is a graph showing a comparison between the abrasion degree of the comparative objects having different intervals of the dimples adjacent to the Ni-SiC plating layer formed by electroplating
Fig. 20 is a photograph showing the wear of the surface of Ni-SiC plated layer electroplated on the surface of the base material and the Ni plated layer electroplated on the surface of the base material, when the base material itself is made of Ni material
21 is a graph comparing the surface friction coefficients of Ni-SiC plated layers electroplated on the surface of the base material with the Ni-plated layers electroplated on the surface of the base material,
22 is a sectional view for explaining a configuration of a hybrid type low friction member according to a modified embodiment of the present invention
23 is a cross-sectional view for explaining the operation and operation of the hybrid type low friction member according to the modified embodiment of the present invention
24 is a photograph for explaining the spray drying method among various methods for forming solid lubricant particles

A hybrid type low friction member and an automobile engine having the hybrid type low friction member combined with the plating and the dimple according to the embodiment of the present invention will be described in detail with reference to the accompanying drawings. The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing. In the accompanying drawings, the dimensions of the structures are enlarged to illustrate the present invention, and are actually shown in a smaller scale than the actual dimensions in order to understand the schematic structure.

Also, the terms first and second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. On the other hand, unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a reference diagram for explaining an inspired technical concept of a hybrid type low friction member according to an embodiment of the present invention; FIG.

The hybrid type low friction member according to the embodiment of the present invention is inspired by the fact that the shark fin shown in nature as shown in Fig. 1 obtains a remarkable friction reduction effect by the patterned pattern formed on the surface thereof It is a unique result obtained as a result of devoting to the development of members for reducing surface friction and abrasion.

The hybrid type low friction member according to the embodiment of the present invention maximizes the low friction effect by first forming a low friction layer on the surface of the base material by electroplating and then forming a dimple pattern in a region where the plating layer is formed. This combination of plating and dimple is expected to be applicable to a variety of products including the cylinder surface of an automobile engine since the friction and wear of the low friction member formed in the hybrid type can be drastically reduced.

Hereinafter, the hybrid type low friction member according to the embodiment of the present invention will be described in more detail.

FIG. 2 is a vertical cross-sectional view for explaining a configuration of a hybrid type low friction member in which plating and dimples are combined according to an embodiment of the present invention. FIGS. 3A to 3 D are cross- Fig. 2 is a series of reference drawings for explaining a manufacturing method of the hybrid type low friction member. Fig.

As shown in the drawing, the low friction member having the plating and the dimples 130 according to the embodiment of the present invention includes a base material 110, a plating layer 120 formed by electroplating on the surface of the base material 110, And a plurality of dimples 130 that form a pattern on the substrate 120 and further enhance the low friction characteristics.

3B and 3C, the plating layer 120 and the dimples 130 are sequentially formed on the surface of the base material 110 shown in FIG. 3A by electroplating, The dimples 130 are formed by laser irradiation as shown in FIG. 2D. This is because a low friction effect of the plating layer 120 and a low friction effect due to a plurality of patterned dimples 130 can be obtained in combination.

If the dimples 130 are temporarily formed on the surface of the base material 110 and then the plating layer 120 is formed by electroplating, the electrolyte solution is uniformly penetrated into the dimples 130 having a small size, It is difficult to uniformly coat the entire surface of the base material 110. In addition, when the dimples 130 are observed in a state where plating is completed, it can be said that it is almost impossible that the dimples 130 remain in a uniform shape with respect to each other while having the original intended diameter and depth. Therefore, a low friction effect of the plating layer 120 by the electroplating and a low friction effect by the dimple 130 pattern can not be obtained in combination. This fact is an important reason why the same technique as the hybrid type low friction member according to the embodiment of the present invention can not be seen because the dimple-like groove is formed on the surface of the electroplated specific member.

In addition, the plating layer 120 is formed to have a thickness of 1.0 mm or less, and it can be said that the application of a composite material of Ni-SiC is the most preferable in terms of low friction effect. As will be described in detail later, the plating layer 120 made of Ni is formed on the surface of the base material 110 by electroplating, compared with a member made of Ni from the beginning, And exhibited the most excellent low friction characteristics when the plating layer 120 was formed of a composite material of Ni-SiC.

The depth of the dimple 130 may be in the range of 0.5 to 1.5 times the diameter of the dimple 130. The dimple 130 may be formed by laser irradiation, However, it is important that the thickness of the plating layer 120 is not limited to the region where the plating layer 120 is formed. Here, the diameter of the dimples 130 may be in the range of 10 to 400 mu m, and the spacing of the adjacent dimples 130 may be in the range of 120 to 180 mu m for improving the low friction characteristics.

Hereinafter, experimental examples of various aspects for confirming the manufacturing and friction reduction effects of the hybrid type low friction member according to the embodiment of the present invention will be described.

- Low friction effect of plating layer formed by electroplating

The composition of the electrolytic bath for forming the plating layer by electroplating on the surface of the base material is as shown in the following table and the base material (iron plate, copper plate) having the size of 1.5 x 1.5 cm is placed on the cathode, (Anode) were placed in a Ti basket (Ti-basket) with Ni balls placed at a distance of about 3 cm from each other, and they were immersed in an electrolyte solution made of Ni-Sulfamate having a purity of 90% or more Electroplating. Cetyltrimethyl ammonium bromide (CTAB) and sodium dodecyl sulphate (SDS) were used as surfactants and corrosion inhibitors, respectively.

Compositions Parameters _{Ni (NH 2 SO 3) 2} (gl -1) 300 NiCl ₂ (gl- ¹ ) 10 H ₃ BO ₃ (gl ^-1 ) 40 β-SiC (gl- ¹ ) 20 SiC size (nm) 270 CTAB (gl- ¹ ) 0.1 Sod. dodecyl sulfate (gl- ¹ ) 0.2

The operation parameters at this time are temperature (° C) of 50, pH of 4, pulse type of current applied, stirring rotation speed (rpm) of 250, ultrasonic frequency (kHz) of 23 to 78, ultrasonic power (W) of 100 ≪ / RTI > However, in case of applied current type and ultrasonic wave, the results are compared with each other. The experimental results can be summarized as follows, with reference to the attached drawings.

Referring to FIG. 4, the shape of the surface of the Ni-SiC plating layer is shown according to the current type used in electroplating and whether ultrasonic waves are applied. In the case where the ultrasonic wave is not applied while performing the electroplating using the direct current, when the ultrasonic wave is not applied while performing the electroplating using the pulse current, As shown in FIG. 4, when the ultrasonic wave is applied while the ultrasonic wave is applied, the electroplating is performed using the pulse current, It can be confirmed that the surface of the plating layer is almost homogenized so that the surface roughness Ra reaches 0.61 mu m when ultrasonic waves are applied. This result is due to the fact that the growth of crystal grains causing the roughness by the synergy effect between the pulse current and the ultrasonic wave and the formation of new nucleation sites are effectively suppressed in addition to the ultrasonic cavitation effect Seems to be.

5 and 6, when the frequency of the applied ultrasonic wave is 38 kHz and the power is 200 W, the Vickers microhardness of the Ni-SiC plating layer is the highest appear. As shown in FIG. 7, Vickers microhardness was highest when ultrasonic waves were applied while electroplating using a pulse current rather than a DC current.

Fig. 8 is a graph showing the relationship between a Ni-SiC plated layer electroplated using only a pulse current (100 Hz, 50% duty cycle) and a Ni-SiC plated layer electro- FIG. 6 is a graph showing the results of an X-ray diffraction analysis to compare internal microstructures of a plated layer. As a result, the intensity of the 200 peak was further reduced due to the reinforcement of 220 and 311 peaks when the ultrasonic waves were applied together with the pulsed current. These results show that the formation of the Ni-SiC plated layer by electroplating while applying ultrasonic waves is more structurally improved than when the ultrasound is not applied.

9 is a graph showing a cross-sectional shape (a) of a Ni-SiC plated layer electroplated using only a pulse current without applying ultrasonic waves and a cross-sectional shape (b) of an electroplated Ni-SiC plated layer using ultrasonic waves Respectively. As a result, it can be seen that the Ni-SiC plated layer electroplated using a pulse current while applying ultrasonic waves has more uniformly dispersed SiC nanoparticles in the Ni matrix. This result implies that the ultrasonic wave inducing high pressure wave and intense vibration acted effectively on penetration of SiC nanoparticles into Ni matrix.

Fig. 10 is a graph showing the relationship between a Ni-SiC plating layer electroplated using a pulsed current and a Ni-SiC plated layer electroplated using a pulse current while applying ultrasonic waves together, Hardness and crystal grain size of Ni. The Vickers microhardness of the electroplated Ni-SiC plated layer using the pulsed current is higher than that of the pure Ni member, and the Vickers microhardness of the electroplated Ni-SiC plated layer is higher than that of the ultrasound plated layer See the left graph). As a result, the Vickers microhardness of each comparative sample seems to be related to the dispersion strengthening and atomization effect. Furthermore, as the number of nucleation sites increases due to the ultrasonic effect and the fusion of nanoparticles, the growth of the crystal grains is disturbed and the crystal grain size becomes smaller and the hardness of the plating layer is increased (see the right graph) .

Fig. 11 is a graph showing the relationship between the Ni-SiC plated layer and the Ni-SiC plated layer electroplated using a pulse current while applying ultrasonic waves together with a pure Ni member, a Ni-SiC plated layer electroplated using only a pulse current without applying ultrasonic waves, And the friction coefficient at this time is compared and analyzed. Here, when comparing the Ni-SiC coating layers, it is confirmed that the effect produced by applying ultrasonic waves during electroplating has a low coefficient of friction and suppression of coarse crystal grains due to uniform dispersion of SiC nanoparticles on the Ni matrix .

Fig. 12 is a graph showing the results of comparison between a pure Ni member, a Ni-SiC plated layer electroplated using only a pulse current without applying ultrasonic waves, and a Ni-SiC plated layer electroplated using a pulse current while applying ultrasonic waves And the degree of corrosion is measured and analyzed. However, this experiment was performed in a 3.5 wt% NaCl solution. This analysis also shows that the electroplated Ni-SiC plated layer with ultrasonic waves together with pulse current exhibited relatively low corrosion current density. Also, in relation to the capacitance loop, the values of the Ni-SiC plated layer added with ultrasonic waves were larger, which means that the resistance to corrosion is higher than that of the other comparators such as resistance to corrosion.

Therefore, it is possible to confirm the excellent low friction characteristics of the electroplated Ni-SiC plated layer by applying the pulse current while applying ultrasonic waves through the comparative analysis of the above-described various aspects.

- Low-friction effect of hybrid structure combining plated layer and dimple

In the following, the results of comparison of the low friction characteristics by forming dimples in various forms on the Ni-SiC plating layer confirmed to have excellent low friction characteristics will be described with reference to the attached drawings.

However, INYA20 and SL-1064-175-254 were used as laser devices for patterning a dimple using a laser, and the parameters used are shown in Table 2 below.

Power Pulse width Marking speed Frequency Wavelength 10 watts 200 ns 300 mm / s 20 kHz 1064 nm

As shown in Table 2, the wavelength of the laser was set to 1064 nm, the output was set to 10 W, the pulse width was set to 200 ns, and the frequency was set to 20 kHz.

FIG. 13 is a photograph of the surface when a plurality of dimples are formed in the Ni-SiC plating layer formed by electroplating, and intervals of neighboring dimples are changed to 80, 100, 150, and 200 μm. The friction materials were compared with each other by a counter ball provided with a steel ball to compare low friction characteristics from various points of view. only. The sliding speed of the counterball was 5 cm / s, the diameter of the counter ball was 12.7 mm, the total sliding distance was 180 m, the lubricant used was low viscosity oil of 5W30, and the applied force was 10N.

As a result of measuring the coefficient of friction while sliding the counter balls against each comparative object, the coefficient of friction was the lowest when the interval between adjacent dimples was 150 μm as shown in FIG. 14, and the friction coefficient was the lowest even when the dimple interval was 100 μm. Respectively. On the other hand, when the dimples were not formed, it was confirmed that the relative friction coefficient was extremely high.

Fig. 15 is a view for comparing the low friction characteristics through the shape of the wear track formed in each comparison object. When the width of the wear track is measured as shown by the red arrow, the width of the neighboring dimples is the narrowest at 150 μm, and the width of the wear track is narrower in the order of the dimple intervals of 200 μm and 300 μm . Such a difference can be more clearly compared with a 3D image through an optical microscope in FIG. On the other hand, in FIG. 17, it can be seen that the abrasion degree of the counterball surface slidingly contacted with the comparative object can be confirmed, and it is confirmed that the abrasion region of the counterball contacted with the comparative object having the adjacent dimple interval of 150 .mu.m is the smallest. Such a difference can be visually understood more clearly when viewed with a 3D image through the optical microscope of FIG. 18, and this result can also be confirmed from FIG. 19 in which the wear area of the counter ball is compared with the numerical value of mm ³ per N mm .

Fig. 20 shows the surface wear of Ni-SiC plated layer electroplated on the surface of the base material and the Ni plated layer electroplated on the surface of the base material in comparison with the case where the base metal itself is made of Ni material. However, in this experiment, dimples were formed for all comparison objects, and adjacent dimple intervals were formed at 150 μm. As a result of comparison, it was confirmed that the width and the wear of the wear track were small when the plating layer was formed by electroplating, compared with the case where the dimples were simply formed on the base material made of Ni material. Especially, It was confirmed that when SiC is used as the material, the width and wear of the wear track are more formed and the low friction property is excellent.

21 is a comparative measurement of the surface friction coefficient of a case where the base material itself is made of a Ni material, a Ni-plated layer electroplated on the surface of the base material, and a Ni-SiC plated layer electroplated on the surface of the base material. However, in this comparison experiment, the adjacent dimple interval was the same as 150 mm, the sliding velocity of the counter ball was 5 cm / s, the sliding total distance was 180 m, the lubricant was low viscosity oil of 5 W30, Respectively.

As a result of the comparative test, as shown in FIG. 21, the Ni-SiC plated layer electroplated with the base material had the lowest friction coefficient. This is attributed to the high hardness and dispersion of SiC nanoparticles when applied to Ni-SiC materials.

As a result of the above-mentioned comparative test results, it was possible to successfully form a Ni-SiC plating layer having excellent low friction characteristics by pulsed electroplating, and when an appropriate level of frequency and power ultrasound is applied in the electroplating process, It can be confirmed that the improvement is significant. Furthermore, it was confirmed that even when the dimple interval adjacent to the plating layer of the Ni material or the plating layer of the Ni-SiC material having a low friction characteristic is patterned to about 150 mu m, the low friction property is further improved.

Next, a hybrid type low friction member according to a modified embodiment of the present invention will be described.

FIG. 22 is a sectional view for explaining a configuration of a hybrid type low friction member according to a modified embodiment of the present invention, and FIG. 23 is a sectional view for explaining the operation and operation of the hybrid type low friction member according to a modified embodiment of the present invention Sectional view.

The hybrid type low friction member according to the modified embodiment of the present invention has a structure in which the plating layer 120 is formed on the surface of the base material 110 by electroplating and the dimple 130 is formed on the plating layer 120 Is characterized in that a spherical solid lubricant particle 140 capable of rolling friction is accommodated in the dimple 130 so as to have a bearing characteristic.

According to the configuration in which the spherical solid lubricant particles 140 are accommodated in the dimple 130, the rolling motion of the solid lubricant particles 140 in the environment in which the contact member M is strongly slidingly contacted with friction, And minimizing the contact area, it is possible to minimize wear and friction of the plating layer 120. Further, depending on the material constituting the solid lubricant particles 140, the debris particles generated as the solid lubricant particles 140 are gradually worn out in the sliding friction contact environment may be mixed with the liquid lubricant to perform additional lubrication .

Here, the solid lubricant particles 140 may be manufactured from a necessary material according to the environment to which the low friction member is applied, or may be prepared by purchasing what is sold. For example, the IF-WS ₂ synthesized by the Weisman Institute in the early 1990s began commercial production in 2002, unlike the platelet-shaped MOS ₂ , which has a spherical shape with a diameter of about 3 to 350 nm. In the case of IF-WS ₂ , it is considered that the IF-WS ₂ can be provided in a micrometer unit suitable to be accommodated in the dimple 130, and is generally known to perform rolling friction between rough surfaces of metal, It is expected that rolling friction can be performed even in the state of being accommodated in the dimple 130.

For reference, the spherical solid lubricant particles 140 can be prepared in various manners only by the present technology. In order to prepare spherical particles, a spray drying method is used. Mold molding method, method of forming sphere by using surface tension while flowing melt or slurry on surface having nano protrusion, method using surface tension provided through cooling process and subsequent process of drying process, method using Lotus effect, 3D And a molding method using a printer.

In addition, on the surface of the solid lubricant particles 140, a plurality of fine oil pockets 141 for receiving a liquid lubricant, such as a surface of a golf ball, are formed. It is possible to form the fine oil pockets 141 on the surface of the solid lubricant particles 140 in various ways. Among them, in the case of the spray drying method and the powder molding method, fine powder particles smaller than the replacement lubricant particles 140 The fine particles are agglomerated on the surface of the previously formed spherical particles and heat-treated in the order as described above. As a result, fine oil pockets 141 are naturally formed between the agglomerated fine powder particles as shown in FIG. In addition, laser processing for forming fine oil pockets 141 by irradiating a laser while rotating spherical particles, micro-discharge machining for pressing fine spherical particle surfaces by using a dimple-shaped tool to form fine oil pockets 141, And a 3D printing method in which particles and fine oil pockets 141 can be simultaneously formed.

The inlet width of the dimples 130 is narrower than the maximum diameter of the solid lubricant particles 140 to prevent the solid lubricant particles 140 from being separated. In order to narrow the inlet of the dimple 130, it is possible to press the low friction member with a press or a device corresponding thereto in a state in which the dimple 130 is formed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is clear that the present invention can be suitably modified and applied in the same manner. Therefore, the above description does not limit the scope of the present invention, which is defined by the limitations of the following claims.

110: base material 120: plated layer
130: Dimple 140: Solid lubricated particle
141: Oil pocket

Claims (18)

A base material;
A plating layer formed on the surface of the base material by electroplating to reduce friction caused by surface contact;
And a plurality of dimples formed on the plating layer so as to further reduce friction caused by surface contact. The method according to claim 1,
Wherein the dimples are formed in a region where the plating layer is formed after the plating layer is formed. 3. The method of claim 2,
Wherein the dimples are formed to a depth not exceeding the thickness of the plating layer. The method of claim 3,
Wherein the thickness of the plating layer is 1.0 mm or less. The method of claim 3,
Wherein the plating layer is made of Ni-SiC. 6. The method of claim 5,
Wherein the ultrasonic wave is applied to the electrolyte solution during the electroplating for forming the plating layer. The method according to claim 6,
Wherein the ultrasonic waves are applied in a frequency range of 30 to 58 kHz within a power range of 150 to 250W. The method according to claim 6,
Wherein the electroplating is pulse electroplating to apply a pulse current. The method of claim 3,
Wherein the plating layer is made of a Ni material. The method of claim 3,
Wherein the diameter of the dimples is in the range of 10 to 400 mu m. 11. The method of claim 10,
Wherein a distance between neighboring dimples is in the range of 120 to 180 mu m. 11. The method of claim 10,
Wherein a depth of the dimple is within a range of 0.5 to 1.5 times the diameter of the dimple. 11. The method of claim 10,
Wherein the dimples are formed by laser irradiation. The method according to claim 1,
Wherein the dimples receive spherical solid lubricant particles having bearing characteristics. ≪ RTI ID = 0.0 > 11. < / RTI > 15. The method of claim 14,
Wherein a plurality of fine oil pockets for receiving a liquid lubricant are formed on a surface of the solid lubricant particle. 15. The method of claim 14,
Wherein the surface of the solid lubricant particle is coated with a liquid lubricant. 16. The method of claim 15,
Wherein an inlet width of the dimples is formed to be narrower than a maximum diameter of the solid lubricant particles to prevent the solid lubricant particles from being separated. An automobile engine using the low friction member according to any one of claims 1 to 17.

Images