JP2019108590A - Slide member and method for producing slide member - Google Patents

Abstract

To provide a technique that can supply a slide face with a lubricant uniformly.SOLUTION: A slide member has a base material, and a porous plating part that is formed on the base material and is a porous plating film of a metal. The surface of the porous plating part constitutes a slide face. In holes of the porous plating part, a lubricant can be held. Since the holes of the porous plating part are uniformly formed in a plating step of the porous plating part, the slide face can be supplied with a lubricant uniformly. Even in the thickness direction of the porous plating part, the holes are uniformly formed, so that an amount of the held lubricant can be increased.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a sliding member and a method of manufacturing the sliding member.

  There is known a bearing having a recess for holding lubricating oil by pressing a large number of molding pins into a sliding surface (see Patent Document 1). In Patent Document 1, the frictional resistance can be reduced by supplying the lubricating oil held in the groove to the sliding surface.

JP, 2011-122710, A

However, in the molding pin of Patent Document 1, since it is not possible to form a minute recess, there is a problem that the supply of lubricating oil is insufficient at a portion far from the recess. Further, since the concave portion can be formed only on the surface of the sliding surface, it is difficult to increase the holding amount of the lubricating oil, and there is a problem that the concave portion disappears due to the progress of wear.
The present invention has been made in view of the above problems, and an object of the present invention is to provide a technology capable of uniformly supplying lubricating oil to a sliding surface.

  In order to achieve the above-mentioned object, the sliding member of the present invention is provided with a substrate and a porous plating part which is a porous plating film of metal formed on the substrate. And the surface of a porous plating part constitutes a sliding face.

  In the present invention configured as described above, since the porous plating portion is a porous plating film, lubricating oil can be held in the pores of the porous plating portion. The pores of the porous plating portion are uniformly formed in the plating step of the porous plating portion, so that the lubricating oil can be uniformly supplied to the sliding surface. In addition, since the holes are formed uniformly in the thickness direction of the porous plating portion, the amount of holding of the lubricating oil can be increased, and the holes for holding the lubricating oil do not disappear even if the wear progresses. can do.

  Moreover, the metal which comprises a porous plating part may be Cu. By forming the porous plated portion with Cu, the strength and the wear resistance can be improved. On the other hand, since there are a large number of holes in the porous plating part, they are easily deformed and compatibility can be achieved at the same time.

  Further, the present invention provides a method of manufacturing a sliding member including a base forming step of forming a base, and a plating step of forming a porous plating portion which is a porous plating film of metal on the base. Is also true.

It is a perspective view of a sliding member concerning an embodiment of the present invention. It is a cross-sectional schematic diagram of a sliding member.

Here, embodiments of the present invention will be described in the following order.
(1) First Embodiment:
(1-1) Configuration of sliding member:
(1-2) Manufacturing Method of Sliding Member:
(2) Other embodiments:

(1) First Embodiment:
(1-1) Configuration of sliding member:
FIG. 1 is a perspective view of a sliding member 1 according to an embodiment of the present invention. The sliding member 1 includes a back metal 10 and a lining 11. The sliding member 1 is a metal member in the shape of a half in which a hollow cylinder is divided into two in the diameter direction, and the cross section thereof has a semicircular arc shape. The sliding bearing A is formed by combining the two sliding members 1 in a cylindrical shape. The slide bearing A bears a cylindrical counterpart shaft 2 (engine crankshaft) at a hollow portion formed inside. The outer diameter of the mating shaft 2 is formed slightly smaller than the inner diameter of the slide bearing A. Lubricating oil (engine oil) is supplied to the gap formed between the outer peripheral surface of the countershaft 2 and the inner peripheral surface of the slide bearing A. At this time, the outer peripheral surface of the mating shaft 2 slides on the inner peripheral surface of the slide bearing A.

  The sliding member 1 has a structure in which the back metal 10 and the lining 11 are sequentially stacked in order of distance from the center of curvature. Therefore, the back metal 10 constitutes the outermost layer of the sliding member 1, and the lining 11 constitutes the innermost layer of the sliding member 1. The back metal 10 and the lining 11 each have a constant thickness in the circumferential direction. The thickness of the back metal 10 is 1.8 mm, and the thickness of the lining 11 is 50 μm. Hereinafter, the inner side means the center of curvature of the sliding member 1, and the outer side means the side opposite to the center of curvature of the sliding member 1. The inner surface of the lining 11 constitutes a sliding surface of the countershaft 2.

  The back metal 10 constitutes the base material of the present invention. The back metal 10 is formed of steel containing 0.15 mass% of C, 0.06 mass% of Mn, and the balance of Fe. In addition, the back metal 10 should just be formed with the material which can support the load from the other axis | shaft 2 through the lining 11, and does not necessarily need to be formed with steel.

  The lining 11 is a layer laminated on the inner side of the back metal 10, and constitutes the porous plating portion of the present invention. The lining 11 consists of Cu and an unavoidable impurity, and content of an unavoidable impurity is 1.0 mass% or less.

  FIG. 2 is a schematic cross-sectional view of the sliding member 1. The lining 11 is porous, and a large number of holes communicate with each other in the lining 11. Further, the holes of the lining 11 are formed uniformly in both the direction of the sliding surface of the lining 11 and the thickness direction. The diameters of the holes in the lining 11 were distributed approximately in the range of 0.1 μm to 3.0 μm, and the average diameter was about 1 μm. The volume ratio of the holes in the lining 11 can be selected from 20 to 70% by volume.

  In the embodiment described above, since the lining 11 is a porous plating film, the lubricating oil can be held in the hole of the lining 11. The holes in the lining 11 are uniformly formed in the plating process of the lining 11, so that the lubricating oil can be uniformly supplied to the sliding surface. In addition, since the holes are formed uniformly in the thickness direction of the lining 11, the holding amount of the lubricating oil can be increased, and the holes for holding the lubricating oil do not disappear even if the wear progresses. Can. Further, by forming the lining 11 of Cu, strength and wear resistance can be improved. On the other hand, since the lining 11 has a large number of holes, it is easily deformed and the compatibility can be compatible.

  Each numerical value shown in the embodiment described above was measured by the following method. The mass of the element constituting each layer of the sliding member 1 was measured by an ICP emission spectrometer (ICPS-8100 manufactured by Shimadzu Corporation). The thickness of each layer was measured by the following procedure. First, the vertical cross section of the sliding member 1 in the axial direction was polished with a cross section polisher (IB-09010 CP, manufactured by Nippon Denshi K.K.). And the image data of the observation image (reflection electron image) was obtained by image | photographing the cross section of the sliding member 1 by the magnification of 7000 times with the electron microscope (JSM-6610A made from JEOL). Then, the film thickness was measured by analyzing the observation image with an image analyzer (Lusex AP manufactured by Nireco).

(1-2) Manufacturing Method of Sliding Member:
First, a flat plate of low carbon steel having the same thickness as the backing metal 10 was prepared (base material forming step).
Next, a lining 11 was formed by laminating Cu to a thickness of 50 μm on the surface of the back metal 10 by electroplating. The procedure of electroplating was as follows. First, the surface of the back metal 10 was washed with water. Furthermore, the unnecessary oxide was removed from the surface of the back metal 10 by pickling the surface of the back metal 10. Thereafter, the surface of the back metal 10 was washed again with water.

  When the above pretreatment was completed, electroplating was performed by supplying a current to the back metal 10 immersed in the plating bath (plating step). A plating bath is prepared by mixing copper pyrophosphate: 94 g / l, potassium pyrophosphate: 340 g / l, aqueous ammonia: 3 ml / l, polyphosphoric acid neutralized benzyltrimethylammonium hydroxide: 0.05 mol / l. did. Benzyltrimethylammonium hydroxide is a water soluble quaternary ammonium compound.

  As an ammonium compound, in place of benzyltrimethylammonium hydroxide, dodecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, phenyltrimethylammonium chloride described in JP-A-2010-121194 Benzyltrimethyl ammonium chloride, benzyl triethyl ammonium chloride, benzyl tributyl ammonium chloride, didecyl dimethyl ammonium chloride, dodecyl dimethyl benzyl ammonium chloride, tetradecyl dimethyl benzyl ammonium chloride, octadecyl dimethyl benzyl ammonium chloride, Octyl methyl ammonium chloride, dodecyl pyridinium chloride, benzyl pyridinium chloride, these bromides, may be mixed into the plating bath, such as sulfate alone or in combination.

The bath temperature of the plating bath adjusted as described above was 55.degree. Further, the current supplied to the back metal 10 is a direct current, and the current density is 3 A / dm ² . In electroplating, the plating bath (liquid) was kept stationary without liquid flow. The plating bath can be adjusted in the range of copper pyrophosphate: 70 to 110 g / l, potassium pyrophosphate: 260 to 400 g / l, and aqueous ammonia: 2 to 4 ml / l. The bath temperature can be adjusted in the range of 50 to 60 ° C., and the current density can be adjusted in the range of 0.5 to 5 A / dm ² . The addition amount of the ammonium compound can be adjusted in the range of 0.001 to 0.1 mol / l.

  The ammonium compound is reductively decomposed at the cathode interface during electroplating, and the non-water-soluble free substance generated by the decomposition is scattered on the plating surface. It is considered that a porous plating film having a large number of fine pores is formed by the liberated substance inhibiting the growth of the plating film of Cu. Since this phenomenon occurs from the early stage of electroplating, a porous plating film can be formed in the entire thickness direction of the lining 11.

  The volume ratio of the holes in the lining 11 can be increased by increasing the current density in electroplating. By increasing the volume ratio of the holes, it is possible to form the sliding member 1 in which importance is attached to low friction resistance and conformability, and by reducing the volume ratio of the holes, it is possible to form the sliding member 1 in which importance is attached to wear resistance. By increasing the volume ratio of the holes in the lining 11, the ratio of holes communicating with each other can be increased. The holes may be formed uniformly, and may or may not communicate.

  After completion of the above electroplating, water washing and drying were performed. As described above, when the sliding member 1 is completed, the sliding bearing A is formed by combining the two sliding members 1 in a cylindrical shape.

(2) Other embodiments:
In the said embodiment, although the sliding member 1 which comprises the sliding bearing A which bears the crankshaft of an engine was illustrated, you may form the sliding bearing A of another use by the sliding member 1 of this invention. For example, the sliding member 1 of the present invention may form a radial bearing such as a gear bushing for a transmission or a piston pin bushing or boss bushing. Furthermore, the sliding member of the present invention may be a thrust bearing, may be various washers, or may be a swash plate for a car air conditioner compressor. Further, the lining 11 is not limited to the porous plating film of Cu, and may be a porous plating film of Ni.

DESCRIPTION OF SYMBOLS 1 ... Sliding member, 2 ... Countering axis, 10 ... Back metal, 11 ... Lining, A ... Bearing

Claims (3)

A substrate,
A porous plating portion which is a porous plating film of metal formed on the substrate;
Equipped with
The surface of the porous plating section constitutes a sliding surface,
Sliding member. The metal is Cu,
The sliding member according to claim 1. A substrate forming step of forming a substrate;
A plating step of forming a porous plating portion which is a porous plating film of metal on the substrate;
A method of manufacturing a sliding member including:

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