JP3650739B2 - SLIDING BODY, MANUFACTURING METHOD THEREOF, AND MECHANICAL SEAL - Google Patents

Description

【０１７２】
【表２】

【０１７３】
【発明の効果】
以上の説明から容易に理解されるように、本発明の摺動体は、耐摩耗性，硬質性等の炭化珪素本来の特性を損なうことなく、潤滑性を大幅に向上させ得るものであり、メカニカルシールの密封環や軸受部材等として好適に使用することができるものである。
【０１７４】
また、本発明の製造方法によれば、かかる摺動体を容易に製造することができる。
【０１７５】
また、本発明のメカニカルシールによれば、シール条件に応じて両密封環又はその一方を上記の摺動体で構成しておくことにより、如何なるシール条件下においても良好なシール機能を発揮させることができる。
【図面の簡単な説明】
【図１】摺動体Ａ１の鏡面を１００倍に拡大して示す顕微鏡写真である。
【図２】摺動体Ａ８の鏡面を１００倍に拡大して示す顕微鏡写真である。
【図３】摺動体Ａ１３の鏡面を１００倍に拡大して示す顕微鏡写真である。
【図４】摺動体Ｂ３の鏡面を１００倍に拡大して示す顕微鏡写真である。
【図５】摺動体Ｂ６の鏡面を１００倍に拡大して示す顕微鏡写真である。
【図６】摺動体Ｂ９の鏡面を１００倍に拡大して示す顕微鏡写真である。
【図７】摺動体Ｂ１０の鏡面を１００倍に拡大して示す顕微鏡写真である。
【図８】端面接触型メカニカルシールの一例を示す縦断側面図である。
【符号の説明】
１…固定環、１ａ…固定環の密封端面、３…回転環（摺動体）、３ａ…回転環の密封端面。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sliding body suitably used for a sealing ring of a mechanical seal, a bearing member, and the like, a manufacturing method thereof, and a mechanical seal using the sliding body as a sealing ring.
[0002]
[Prior art]
For example, as a mechanical seal, as shown in FIG. 8, a seal ring (hereinafter referred to as “fixed ring”) 1 fixed and held in a seal case 2 and a rotary shaft 4 are held so as to be movable in the axial direction and not relatively rotatable. A spring that is interposed between a sealing ring (hereinafter referred to as “rotating ring”) 3, a spring retainer 5 fixed to the rotating shaft 4, and the rotating ring 3, and presses and urges the rotating ring 3 toward the fixed ring 1. 6, by the relative rotational sliding action of the sealing end faces 1 a, 3 a which are the opposed end faces of both sealing rings 1, 3, the machine inner area A which is the outer peripheral area of the relative rotational sliding contact portion and the machine which is the inner peripheral area An end surface contact type configured to seal the outside air region B is well known.
[0003]
By the way, since silicon carbide is hard and excellent in wear resistance and excellent in thermal, chemical and mechanical properties, generally, the above-described sliding rings such as a sealing ring of a mechanical seal and a bearing member are used. Used as a component of moving objects.
[0004]
However, since silicon carbide does not have self-lubricating properties such as carbon, there is a problem that the sliding body made of silicon carbide is liable to be worn or heated due to relative sliding with the counterpart member.
[0005]
Therefore, conventionally, in order to improve the slidability, the sliding body is made of a porous silicon carbide sintered material, and the pores are impregnated with a low friction material such as oil or fluororesin, or silver. Sliding body made of composite silicon carbide sintered material infiltrated with low friction metal materials such as lead, antimony, etc., or fine solid lubricant (carbon, graphite, boron nitride, molybdenum disulfide, etc.) dispersed It has been proposed to construct
[0006]
[Problems to be solved by the invention]
However, in the former case, since the bonding force between silicon carbides in the porous silicon carbide sintered material is weak, the wear resistance is inferior, and the durability as a sliding body is problematic. Moreover, when the sliding surface becomes high temperature due to frictional heat, the impregnating material and the infiltrating material evaporate from the sliding surface or deteriorate due to oxidation, and the friction coefficient increases.
[0007]
In the latter case, since the lubricant that hinders the sintering behavior is dispersed throughout the sintered material, the density and strength (bending strength) are lowered and the wear resistance is poor. Further, although the lubricant particles such as graphite particles are bonded to the silicon carbide particles to some extent, the bonding force (sintering force) is weak. Accordingly, the silicon carbide particles may be separated at the boundary between the two, and this may be interposed between the sliding surfaces, so-called a grindstone action may occur, and the sliding surfaces may be damaged. Moreover, in order to ensure sufficient lubricity, it is necessary to contain a large amount of lubricant, but if this is done, the above-described problems become more prominent.
[0008]
As described above, in any case, by improving the lubricity, the original characteristics (such as wear resistance) of silicon carbide are greatly reduced, and the function as the sliding body cannot be improved.
[0009]
The present invention has been made in view of such points, and provides a sliding body capable of significantly improving lubricity while ensuring the original characteristics of silicon carbide, and suitably manufacturing the same. It is an object of the present invention to provide a mechanical seal capable of exhibiting a good sealing function by using it as a sealing ring.
[0010]
[Means for Solving the Problems]
In the present invention, first, in order to achieve the above-mentioned object, a composite silicon carbide structure bonded to silicon carbide particles in a state where fine solid lubricant particles are densely bonded independently bonds silicon carbide particles to each other. The present invention proposes a sliding body comprising a composite silicon carbide sintered material dispersed in a dense single silicon carbide structure.
[0011]
In such a sliding body, a portion forming a single silicon carbide structure in which a portion forming a composite silicon carbide structure (hereinafter referred to as “composite silicon carbide structure portion”) is a base material portion (hereinafter referred to as “single silicon carbide structure portion”). In each composite silicon carbide structure portion, a large number of fine solid lubricant particles are blended in a dense state. That is, the surface of the sliding body, that is, the sliding surface has a form as if the large-diameter solid lubricant is arranged in the form of dots. Therefore, the sliding surface has a lubricity (self-lubricating) equal to or higher than that in the case where a large number of fine solid lubricant particles are uniformly distributed over the entire sliding surface in a state of being close to each other. Will be secured.
[0012]
On the other hand, in the composite silicon carbide structure portion, as in the case of the composite silicon carbide sintered material described at the beginning, the bonding force (sintering force) between the solid lubricant particles and the silicon carbide particles is very weak. However, the ratio of the composite silicon carbide structure portion in the entire sliding body is extremely small compared to the single silicon carbide structure portion, and the composite silicon carbide structure portion is completely composed of a sufficiently large single silicon carbide structure portion. Therefore, the composite silicon carbide sintered material (and the porous silicon carbide sintered material described in the beginning) have high bonding strength between particles as a whole of the sliding body, and the density (sintering density) and strength (bending strength). This is a significant improvement compared to the binder.
[0013]
That is, the single silicon carbide structure portion contracts greatly during sintering (generally, silicon carbide has a volume reduction of about ½ during sintering), so the composite silicon carbide structure portion surrounds it. It will be strongly compressed by the contraction force of the single silicon carbide structure. As a result, the interparticle bonding force in the composite silicon carbide structure portion is greatly increased by the compression action from the outer peripheral side due to the shrinkage of the single silicon carbide structure portion described above, even though the bonding force itself due to sintering is weak. . Further, at the boundary portion between the composite silicon carbide structure and the single silicon carbide structure, the bonding action by sintering silicon carbide particles and the bonding force increasing action by the compression action are equivalent to those in the single silicon carbide structure. Bonding force between particles is ensured. Accordingly, not only the interparticle bonding force in the single silicon carbide structure part, but also the interparticle bonding force in the composite silicon carbide structure part and the bonding force between both structure parts are increased. As a result, the sintered density and strength are improved. Occurrence of the degranulation phenomenon can be reliably prevented.
[0014]
As described above, the composite silicon carbide material having the above-described structure has improved lubricity in an inclined manner from the single silicon carbide structure portion to the composite silicon carbide structure portion, and the interparticle bonding force is the center of the composite silicon carbide structure portion. From the point that it increases in a gradient from a single carbonized structure portion, it is said that it is a functionally graded material in which a solid lubricant excellent in lubricity is added to silicon carbide excellent in wear resistance and the like. Therefore, the lubricity can be improved without impairing the original characteristics of silicon carbide.
[0015]
Thus, graphite, carbon black, boron nitride or the like having a particle diameter of 1 to 100 μm is generally used as the solid lubricant. In order to improve the lubricity by the composite silicon carbide structure described above, the solid lubricant content in the composite silicon carbide structure (hereinafter referred to as “local lubricant content”) is 10% or more (more preferably 20%). The composite silicon carbide portion has a diameter of 20 μm or more, and the solid lubricant content in the carbide composite silicon carbide sintered material (hereinafter referred to as “total lubricant content”) is 2% or more (more preferably 4%). The above is preferable. Further, in order to sufficiently exhibit the effect of increasing the bonding force between particles due to the contraction of the single silicon carbide structure portion, and to ensure the original characteristics of silicon carbide, the local lubricant content is set to 50% or less, and composite silicon carbide The diameter of the portion is preferably 50 μm or less, and the total lubricant content is preferably 25% or less (more preferably 20% or less, still more preferably 10% or less). That is, in order to improve lubricity without impairing the original characteristics of silicon carbide, the local lubricant content is set to 10 to 50% (more preferably 20 to 50%), and the diameter of the composite silicon carbide portion is set to 20%. It is preferable that the total lubricant content is 2 to 25% (more preferably 4 to 20%, still more preferably 4 to 10%). The local lubricant content or the total lubricant content is the ratio of the solid lubricant content to the total content of silicon carbide and solid lubricant in the composite silicon carbide structure or single silicon carbide structure (= (solid lubrication Material content) × 100 / (content of silicon carbide + content of solid lubricant)).
[0016]
In addition, the present invention secondly, a pre-granulated material obtained by granulating a composite silicon carbide sintered raw material in which fine solid lubricant particles are mixed and dispersed in order to suitably manufacture the above-described sliding body, This granulated material obtained by mixing with a single silicon carbide sintered raw material that does not contain a solid lubricant and granulating the mixed slurry is pressure-formed into a predetermined shape, and the pressure-formed body is fired. Thus, the composite silicon carbide structure in which the solid silicon carbide particles bonded to the silicon carbide particles in a state where the solid lubricant particles are densely dispersed is dispersed independently in the dense single silicon carbide structure in which the silicon carbides are bonded to each other. Provided is a method of manufacturing a sliding body characterized in that a material is obtained.
[0017]
According to this method, a composite silicon carbide structure is formed by the preliminary granulated material contained in a part of the present granulated material. Accordingly, the local lubricant content can be easily controlled by the content of silicon carbide and solid lubricant in the pre-granulated material, that is, the composite silicon carbide sintered raw material, and the silicon carbide content in the single silicon carbide sintered raw material The total lubricant content can be easily controlled by the amount and the added amount of the pre-granulated material. That is, the preferable ranges of the solid lubricant content in the composite silicon carbide sintered raw material and the solid lubricant content in the mixed slurry that is the raw material of the granulated material are the local lubricant content and the overall lubricant, respectively. It corresponds to the above-mentioned preferable range in content. The solid lubricant content is the ratio of the solid lubricant content to the total content of silicon carbide and solid lubricant, as with the local lubricant content and the overall lubricant content. Moreover, although the diameter of the composite silicon carbide structure portion is determined by the diameter of the preliminary granulated material or the present granulated material, these can be arbitrarily controlled.
[0018]
Further, since the pre-granulated material is for forming a composite silicon carbide structure, the granule form (granulated form) of the pre-granulated material is destroyed when mixed with a single silicon carbide sintered raw material. And the composite silicon carbide structure of an independent form cannot be formed appropriately. Therefore, it is necessary to use a polymer auxiliary contained in the composite silicon carbide sintered raw material that does not dissolve in the solvent contained in the single silicon carbide sintered raw material in order to adjust the preliminary granulated material. is there. For example, when methanol is used as the solvent used when adjusting the mixed slurry, polyvinyl alcohol is used as a polymer auxiliary for adjusting the pre-granulated material.
[0019]
Thirdly, the present invention proposes a mechanical seal characterized in that at least one of the sealing rings is constituted by the above-described sliding body in the mechanical seal configured so that the two sealing rings are in relative sliding contact with each other. To do. According to such a mechanical seal, since the sliding body is excellent in lubricity in addition to the inherent characteristics of silicon carbide (such as wear resistance) as described above, the constituent material of the mating seal ring can be selected according to the sealing conditions. By selecting them appropriately, a satisfactory sealing function can be exhibited under any sealing conditions. In particular, when both sealing rings are constituted by the sliding body of the present invention, a good sealing function can be exhibited even under severe conditions such as when handling a slurry.
[0020]
【Example】
As Example 1, the sliding body A1 of the present invention that can be used as the rotating ring 3 of the mechanical seal (hereinafter referred to as “the mechanical seal”) having the configuration shown in FIG. Produced by mixing process, main granulation process, preforming process, firing process and finishing process.
[0021]
Pre-granulation step: 80 g of α-type silicon carbide (α-SiC) powder having an average particle size of 0.7 μm and boron carbide (B _Four C) Particle diameter of solid lubricant in presintered raw material consisting of 0.4 g of powder and 1 g of polyvinyl alcohol (PVA # 1000) having an average molecular weight of 1000 which is a polymer assistant dissolved in 200 g of water 20 g of 1 μm graphite powder was added, and these were mixed for 24 hours by a ball mill, and the composite silicon carbide sintered raw material (solid lubricant content: 20%) as a mixed solution was spray-dried by a spray dryer. Granules (granulated) were obtained to obtain a spherical pre-granulated material (granule) having a diameter of 20 to 80 μm.
[0022]
Sintering raw material mixing step: 90 g of α-SiC powder having an average particle size of 0.7 μm and B as a sintering aid _Four 0.45 g of C powder, 4 g of a phenol resin (residual carbon ratio 50%) as a carbon source, 2 g of polyethylene glycol (PEG # 6000) with an average molecular weight of 6000 as a molding aid and 1 g of stearic acid are added, and these are added with a solvent A single silicon carbide sintered raw material was obtained by mixing with methanol in a ball mill for 24 hours.
[0023]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 10 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture is stirred for a period of time, and the mixed slurry (content ratio of solid lubricant: 2%) is granulated by spray drying with a spray dryer (granulated), and the spherical shaped granulated material having a diameter of 20 to 80 μm ( Granules).
[0024]
Preliminary molding step: The granulated material obtained in the granulating step is filled in a predetermined mold, and then 1500 kg / cm. ² Was subjected to cold press molding to obtain a preform having an annular shape corresponding to the rotating ring 3. The shape of the preform is set in consideration of shrinkage during sintering.
[0025]
Firing step: The pre-formed body obtained in the pre-forming step is fired in an argon atmosphere at 2150 ° C. without applying pressure to obtain a composite silicon carbide sintered material having a sealed ring shape corresponding to the rotating ring 3. It was.
[0026]
Finishing step: A sliding body A1 that can be used as the rotating ring 3 was obtained by polishing (wrapping) the end surface of the composite silicon carbide sintered material obtained in the firing step to a mirror surface of Ra = 0.05. The mirror surface of the sliding body A1 functions as a sliding surface (sealed end surface 3a) when used as the rotating ring 3.
[0027]
In addition, as Example 2, the sliding body A2 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following pre-granulation step, sintering raw material mixing step, main granulation step, pre-forming step, Manufactured by firing process and finishing process. The preliminary granulation step, firing step and finishing step are the same as in Example 1. The sintering raw material mixing step and the main granulation step are α-SiC, B _Four Example 1 is the same as Example 1 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0028]
Pre-granulation step: By the same pre-granulation step as in Example 1, the same pre-granulation material as in Example 1 was obtained.
[0029]
Sintering raw material mixing step: 80 g of α-SiC powder and B _Four 0.4 g of C powder, 3.5 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol for 24 hours by a ball mill to obtain a single silicon carbide sintered raw material.
[0030]
Main granulation step: The single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 20 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was agitated and mixed for a period of time, and the mixed slurry (solid lubricant content: 2%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0031]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 1.
[0032]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 1 to obtain a composite silicon carbide sintered material having the same shape as in Example 1.
[0033]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 1 to obtain a sliding body A2 that could be used as the rotating ring 3.
[0034]
In addition, as Example 3, the sliding body A3 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following pre-granulation step, sintering raw material mixing step, main granulation step, pre-forming step, Manufactured by firing process and finishing process. The preliminary granulation step, firing step and finishing step are the same as in Example 1. The sintering raw material mixing step and the main granulation step are α-SiC, B _Four Example 1 is the same as Example 1 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0035]
Pre-granulation step: By the same pre-granulation step as in Example 1, the same pre-granulation material as in Example 1 was obtained.
[0036]
Sintering raw material mixing process: α-SiC powder 70g, B _Four 0.35 g of C powder, 3 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol in a ball mill for 24 hours to obtain a single silicon carbide sintered raw material.
[0037]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 30 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred for a period of time, and the mixed slurry (solid lubricant content: 6%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0038]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 1.
[0039]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Example 1 to obtain a composite silicon carbide sintered material having the same shape as in Example 1.
[0040]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 1 to obtain a sliding body A3 that could be used as the rotating ring 3.
[0041]
In addition, as Example 4, the sliding body A4 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following pre-granulation step, sintering raw material mixing step, main granulation step, pre-forming step, Manufactured by firing process and finishing process. The preliminary granulation step, firing step and finishing step are the same as in Example 1. The sintering raw material mixing step and the main granulation step are α-SiC, B _Four The same as Example 1 except that the addition amount of C, phenol resin and pre-granulated material is different.
[0042]
Pre-granulation process: By the same pre-granulation process as Example 1, the same pre-granulation material as Example 1 was obtained.
[0043]
Sintering raw material mixing process: α-SiC powder 50g, B _Four 0.25 g of C powder, 2 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol in a ball mill for 24 hours to obtain a single silicon carbide sintered raw material.
[0044]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 50 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a time, and the mixed slurry (solid lubricant content: 10%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0045]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 1.
[0046]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Example 1 to obtain a composite silicon carbide sintered material having the same shape as in Example 1.
[0047]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 1 to obtain a sliding body A4 that could be used as the rotating ring 3.
[0048]
Further, as Example 5, the sliding body A5 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following pre-granulation step, sintering raw material mixing step, main granulation step, pre-forming step, Manufactured by firing process and finishing process. The firing process and the finishing process are the same as in Example 1. The preliminary granulation process, the sintering raw material mixing process, and the main granulation process are solid lubricant, α-SiC, B _Four The same as Example 1 except that the addition amount of C, phenol resin and pre-granulated material is different.
[0049]
Pre-granulation step: α-SiC powder 60g, B _Four 40 g of graphite powder is added to a pre-sintered raw material composed of 0.3 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these are mixed by a ball mill for 24 hours, and composite silicon carbide as the mixed liquid The sintered raw material (solid lubricant content: 40%) was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0050]
Sintering raw material mixing process: α-SiC powder 70g, B _Four 0.35 g of C powder, 3 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol in a ball mill for 24 hours to obtain a single silicon carbide sintered raw material.
[0051]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is put in a stirring vessel, and 50 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (solid lubricant content: 20%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0052]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 1.
[0053]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 1 to obtain a composite silicon carbide sintered material having the same shape as in Example 1.
[0054]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 1 to obtain a sliding body A5 that could be used as the rotating ring 3.
[0055]
In addition, as Example 6, the sliding body A6 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following preliminary granulation step, sintering raw material mixing step, main granulation step, preliminary molding step, Manufactured by firing process and finishing process. The firing process and the finishing process are the same as those in Example 1. The preliminary granulation process, the sintering raw material mixing process, and the main granulation process were performed using carbon black as the solid lubricant and the solid lubricant, α- SiC, B _Four Example 1 is the same as Example 1 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0056]
Pre-granulation step: α-SiC powder 80g, B _Four 20 g of carbon black powder having a particle size of 0.02 μm was added to a pre-sintered raw material consisting of 0.4 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these were mixed by a ball mill for 24 hours. The composite silicon carbide sintered raw material (solid lubricant content: 20%) as the mixed liquid was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0057]
Sintering raw material mixing step: 80 g of α-SiC powder and B _Four 0.4 g of C powder, 3.5 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol for 24 hours by a ball mill to obtain a single silicon carbide sintered raw material.
[0058]
Main granulation step: The single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 20 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (solid lubricant content: 4%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0059]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 1.
[0060]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 1 to obtain a composite silicon carbide sintered material having the same shape as in Example 1.
[0061]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 1 to obtain a sliding body A6 that could be used as the rotating ring 3.
[0062]
In addition, as Example 7, the sliding body A7 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following pre-granulation step, sintering raw material mixing step, main granulation step, pre-forming step, Manufactured by firing process and finishing process. The preliminary granulation step, the sintering raw material mixing step, the firing step, and the finishing step are the same as in Example 6. The sintering raw material mixing step and the main granulation step are different in the amount of addition of the preliminary granulated material. Except for, the same as Example 6.
[0063]
Pre-granulation step: By the same pre-granulation step as in Example 6, the same pre-granulation material as in Example 6 was obtained.
[0064]
Sintering raw material mixing step: By the same sintering raw material mixing step as in Example 6, the same single silicon carbide sintering raw material as in Example 6 was obtained.
[0065]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is put in a stirring vessel, and 50 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (solid lubricant content: 10%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0066]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 6.
[0067]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 6 to obtain a composite silicon carbide sintered material having the same shape as in Example 6.
[0068]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 6 to obtain a sliding body A7 that could be used as the rotating ring 3.
[0069]
In addition, as Example 8, the sliding body A8 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following preliminary granulation step, sintering raw material mixing step, main granulation step, preliminary molding step, Manufactured by firing process and finishing process. The sintering raw material mixing step, the firing step and the finishing step are the same as in Example 6. The preliminary granulation step and the main granulation step are solid lubricant, α-SiC, B _Four Example 6 is the same as Example 6 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0070]
Pre-granulation step: α-SiC powder 50g, B _Four 50 g of carbon black powder is added to a pre-sintered raw material consisting of 0.25 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these are mixed by a ball mill for 24 hours. A silicon granulated raw material (solid lubricant content: 50%) was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0071]
Sintering raw material mixing step: By the same sintering raw material mixing step as in Example 6, the same single silicon carbide sintering raw material as in Example 6 was obtained.
[0072]
Main granulation step: The single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 20 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a time, and the mixed slurry (solid lubricant content: 10%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0073]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 6.
[0074]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 6 to obtain a composite silicon carbide sintered material having the same shape as in Example 6.
[0075]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 6 to obtain a sliding body A8 that could be used as the rotating ring 3.
[0076]
In addition, as Example 9, the sliding body A9 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following pre-granulation step, sintering raw material mixing step, main granulation step, pre-forming step, Manufactured by firing process and finishing process. The firing process and the finishing process are the same as in Example 6. The preliminary granulation process, the sintering raw material mixing process, and the main granulation process are solid lubricant, α-SiC, B _Four Example 6 is the same as Example 6 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0077]
Pre-granulation step: α-SiC powder 50g, B _Four 50 g of carbon black powder is added to a pre-sintered raw material consisting of 0.25 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these are mixed by a ball mill for 24 hours. A silicon granulated raw material (solid lubricant content: 50%) was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0078]
Sintering raw material mixing process: α-SiC powder 70g, B _Four 0.35 g of C powder, 3 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol in a ball mill for 24 hours to obtain a single silicon carbide sintered raw material.
[0079]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 30 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (the solid lubricant content: 15%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0080]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 6.
[0081]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 6 to obtain a composite silicon carbide sintered material having the same shape as in Example 6.
[0082]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 6 to obtain a sliding body A9 that could be used as the rotating ring 3.
[0083]
In addition, as Example 10, the sliding body A10 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following preliminary granulation step, sintering raw material mixing step, main granulation step, preliminary molding step, Manufactured by firing process and finishing process. The firing process and the finishing process are the same as in Example 6. The preliminary granulation process, the sintering raw material mixing process, and the main granulation process are solid lubricant, α-SiC, B _Four Example 6 is the same as Example 6 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0084]
Pre-granulation step: α-SiC powder 60g, B _Four 40 g of carbon black powder is added to a pre-sintered raw material composed of 0.3 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these are mixed by a ball mill for 24 hours, and the composite carbonization as the mixed liquid A silicon granulated raw material (solid lubricant content: 40%) was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0085]
Sintering raw material mixing process: α-SiC powder 70g, B _Four 0.35 g of C powder, 3 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol in a ball mill for 24 hours to obtain a single silicon carbide sintered raw material.
[0086]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 50 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (solid lubricant content: 20%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0087]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 6.
[0088]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 6 to obtain a composite silicon carbide sintered material having the same shape as in Example 6.
[0089]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 6 to obtain a sliding body A10 that could be used as the rotating ring 3.
[0090]
In addition, as Example 11, the sliding body A11 of the present invention that can be used as the rotating ring 3 of the mechanical seal includes the following preliminary granulation step, sintering raw material mixing step, main granulation step, preliminary molding step, Manufactured by firing process and finishing process. The firing process and the finishing process are the same as in Example 6. The preliminary granulation process, the sintering raw material mixing process, and the main granulation process are solid lubricant, α-SiC, B _Four Example 6 is the same as Example 6 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0091]
Pre-granulation step: α-SiC powder 50g, B _Four 40 g of carbon black powder is added to a pre-sintered raw material consisting of 0.25 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these are mixed by a ball mill for 24 hours. A silicon sintered raw material (solid lubricant content: 40%) was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0092]
Sintering raw material mixing process: α-SiC powder 70g, B _Four 0.35 g of C powder, 3 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol in a ball mill for 24 hours to obtain a single silicon carbide sintered raw material.
[0093]
Main granulation step: A single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 50 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (solid lubricant content: 20%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0094]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 6.
[0095]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 6 to obtain a composite silicon carbide sintered material having the same shape as in Example 6.
[0096]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 6 to obtain a sliding body A11 that could be used as the rotating ring 3.
[0097]
In addition, as Example 12, the sliding body A12 of the present invention that can be used as the rotating ring 3 of the mechanical seal includes the following pre-granulation step, sintering raw material mixing step, main granulation step, pre-forming step, Manufactured by firing process and finishing process. The firing process and the finishing process are the same as those in Example 6. The preliminary granulation process, the sintering raw material mixing process, and the main granulation process were performed using a β-type silicon carbide, the amount of addition, and the solid content. Lubricant, B _Four Example 6 is the same as Example 6 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0098]
Pre-granulation step: 80 g of β-type silicon carbide (β-SiC) powder having an average particle size of 0.6 μm, B _Four 20 g of carbon black powder is added to a pre-sintered raw material composed of 0.4 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these are mixed by a ball mill for 24 hours, and the composite carbonization as the mixed liquid A silicon granulated raw material (solid lubricant content: 20%) was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0099]
Sintering raw material mixing step: To 80 g of β-SiC powder having an average particle size of 0.6 μm, _Four 0.4 g of C powder, 3.5 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol for 24 hours by a ball mill to obtain a single silicon carbide sintered raw material.
[0100]
Main granulation step: The single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 20 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (solid lubricant content: 4%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0101]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 6.
[0102]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 6 to obtain a composite silicon carbide sintered material having the same shape as in Example 6.
[0103]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 6 to obtain a sliding body A12 that could be used as the rotating ring 3.
[0104]
In addition, as Example 13, the sliding body A13 of the present invention that can be used as the rotating ring 3 of the mechanical seal has the following preliminary granulation step, sintering raw material mixing step, main granulation step, preliminary molding step, Manufactured by firing process and finishing process. The preliminary granulation step, the firing step and the finishing step are the same as those in Example 1. The sintering raw material mixing step and the main granulation step were performed using boron nitride as the solid lubricant and the solid lubricant, α- SiC, B _Four Example 1 is the same as Example 1 except that the addition amounts of C, phenol resin, and pre-granulated material are different.
[0105]
Pre-granulation step: α-SiC powder 80g, B _Four 20 g of boron nitride (BN) powder having a particle diameter of 10 μm is added to a pre-sintered raw material consisting of 0.4 g of C powder and a solution obtained by dissolving 1 g of PVA in 200 g of water, and these are mixed by a ball mill for 24 hours. The composite silicon carbide sintered raw material (solid lubricant content: 20%), which is the mixed liquid, was granulated by spray drying with a spray dryer to obtain a pre-granulated material.
[0106]
Sintering raw material mixing step: 80 g of α-SiC powder and B _Four 0.4 g of C powder, 3.5 g of phenol resin, 2 g of PEG and 1 g of stearic acid were added, and these were mixed with methanol for 24 hours by a ball mill to obtain a single silicon carbide sintered raw material.
[0107]
Main granulation step: The single silicon carbide sintered raw material obtained in the sintering raw material mixing step is placed in a stirring vessel, and 20 g of the pre-granulated material obtained in the pre-granulation step is added thereto, The mixture was stirred and mixed for a period of time, and the mixed slurry (solid lubricant content: 4%) was granulated by spray drying with a spray dryer to obtain the granulated material.
[0108]
Preliminary molding step: Using the granulated material obtained in the granulating step, a preformed body was obtained by the same preforming step as in Example 1.
[0109]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 1 to obtain a composite silicon carbide sintered material having the same shape as in Example 1.
[0110]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 1 to obtain a sliding body A13 that could be used as the rotating ring 3.
[0111]
Further, as Comparative Example 1, a sliding body B1 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. Note that the preforming step, firing step, and finishing step are the same as in Example 1.
[0112]
Granulation step: 98 g of α-SiC powder having an average particle size of 0.7 μm and B as a sintering aid _Four 0.45 g of C powder, 2 g of carbon black as a carbon source, 2 g of PEG (# 6000) as a molding aid and 1 g of stearic acid, and 1 g of PVA (# 1000) as a polymer assistant are dissolved in 200 g of water. 2 g of graphite powder having a particle diameter of 1 μm is added as a solid lubricant to a silicon carbide sintered raw material made of the dissolved solution, and these are mixed with a ball mill for 24 hours. The mixed slurry (content ratio of solid lubricant: 2 %) Was granulated by spray drying with a spray dryer to obtain a spherical granulated material having a diameter of 20 to 80 μm.
[0113]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Example 1.
[0114]
Firing step: The preform obtained in the preforming step was fired in the same firing step as in Example 1 to obtain a composite silicon carbide sintered material having the same shape as in Example 1.
[0115]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Example 1 to obtain a sliding body B1 that could be used as the rotating ring 3.
[0116]
Further, as Comparative Example 2, a sliding body B2 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step, and the finishing step are the same as in Comparative Example 1, and the granulation step is the same as in Comparative Example 1 except that the addition amount of α-SiC and solid lubricant is different.
[0117]
Granulation step: 10 g of graphite powder as a solid lubricant was added to the same silicon carbide sintered raw material as in Comparative Example 1 except that the amount of α-SiC powder added was 90 g, and these were added by a ball mill for 24 hours. After mixing, the mixed slurry (solid lubricant content: 10%) was granulated by spray drying with a spray dryer to obtain a granulated material.
[0118]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0119]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0120]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B2 that could be used as the rotating ring 3.
[0121]
Further, as Comparative Example 3, a sliding body B3 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step, and the finishing step are the same as in Comparative Example 1, and the granulation step is the same as in Comparative Example 1 except that the addition amount of α-SiC and solid lubricant is different.
[0122]
Granulation step: 20 g of graphite powder as a solid lubricant was added to the same silicon carbide sintered raw material as in Comparative Example 1 except that the amount of α-SiC powder added was 80 g, and these were added by a ball mill for 24 hours. The mixed slurry (solid lubricant content: 20%) was granulated by spray drying with a spray dryer to obtain a granulated material.
[0123]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0124]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0125]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B3 that could be used as the rotating ring 3.
[0126]
Further, as Comparative Example 4, a sliding body B4 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step and the finishing step are the same as in Comparative Example 1, and the granulation step is different in that carbon black is used as the solid lubricant and the amount of α-SiC and solid lubricant added is different. Except for this, it is the same as Comparative Example 1.
[0127]
Granulation step: 10 g of carbon black powder having a particle diameter of 0.02 μm was added as a solid lubricant to the same silicon carbide sintered raw material as in Comparative Example 1 except that the amount of α-SiC powder added was 90 g. These were mixed in a ball mill for 24 hours, and the mixed slurry (solid lubricant content: 10%) was granulated by spray drying with a spray dryer to obtain a granulated material.
[0128]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0129]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0130]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B4 that could be used as the rotating ring 3.
[0131]
Further, as Comparative Example 5, a sliding body B5 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step, and the finishing step are the same as those in Comparative Example 1, and the granulating step is the same as that in Comparative Example 4 except that the addition amounts of α-SiC and solid lubricant are different.
[0132]
Granulation step: 15 g of carbon black powder is added to the same silicon carbide sintered raw material as in Comparative Example 4 except that the amount of α-SiC powder added is 85 g, and these are mixed by a ball mill for 24 hours. The mixed slurry (solid lubricant content: 15%) was granulated by spray drying with a spray dryer to obtain a granulated material.
[0133]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0134]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0135]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B5 that could be used as the rotating ring 3.
[0136]
Further, as Comparative Example 6, a sliding body B6 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step, and the finishing step are the same as those in Comparative Example 1, and the granulating step is the same as that in Comparative Example 4 except that the addition amounts of α-SiC and solid lubricant are different.
[0137]
Granulation step: 25 g of carbon black powder was added to the same silicon carbide sintered raw material as in Comparative Example 4 except that the amount of α-SiC powder added was 75 g, and these were mixed in a ball mill for 24 hours. The mixed slurry (solid lubricant content: 25%) was granulated by spray drying with a spray dryer to obtain a granulated material.
[0138]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0139]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0140]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B6 that could be used as the rotating ring 3.
[0141]
Further, as Comparative Example 7, a sliding body B7 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step, and the finishing step are the same as in Comparative Example 1, and the granulation step is the same as in Comparative Example 4 except that β-SiC is used.
[0142]
Granulation step: 10 g of carbon black powder was added to the same silicon carbide sintered raw material as in Comparative Example 4 except that 90 g of β-SiC powder having an average particle diameter of 0.6 μm was used instead of α-SiC powder. These were mixed for 24 hours by a ball mill, and the mixed slurry (solid lubricant content: 10%) was granulated by spray drying with a spray dryer to obtain a granulated material.
[0143]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0144]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0145]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B7 that could be used as the rotating ring 3.
[0146]
Moreover, as Comparative Example 8, a sliding body B8 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step, and the finishing step are the same as in Comparative Example 1, and the granulation step is the same as in Comparative Example 2 except that BN is used as the solid lubricant.
[0147]
Granulation step: To the same silicon carbide sintered raw material as in Comparative Example 2, 10 g of BN powder having a particle diameter of 10 μm was added as a solid lubricant, and these were mixed by a ball mill for 24 hours. The granulated material was obtained by granulation by spray drying with a spray dryer.
[0148]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0149]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0150]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B8 that could be used as the rotating ring 3.
[0151]
Further, as Comparative Example 9, a sliding body B9 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, the firing step, and the finishing step are the same as those in Comparative Example 1, and the granulation step is the same as that in Comparative Example 8 except that the addition amount of α-SiC and solid lubricant is different.
[0152]
Granulation step: 20 g of BN powder as a solid lubricant is added to the same silicon carbide sintered raw material as in Comparative Example 8 except that the amount of α-SiC added is 80 g, and these are mixed in a ball mill for 24 hours. Then, the mixed slurry (solid lubricant content: 20%) was granulated by spray drying with a spray dryer to obtain a granulated material.
[0153]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0154]
Firing step: The preformed body obtained in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a composite silicon carbide sintered material having the same shape as Comparative Example 1.
[0155]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B9 that could be used as the rotating ring 3.
[0156]
Further, as Comparative Example 10, a sliding body B10 that can be used as the rotating ring 3 of the mechanical seal was manufactured by the following granulation process, pre-forming process, firing process, and finishing process. The preforming step, firing step, and finishing step are the same as those in Comparative Example 1.
[0157]
Granulation step: 100 g of β-SiC powder having an average particle size of 0.6 μm was added to B as a sintering aid. _Four Add 0.5 g of C powder and 4 g of phenol resin (resol type) as a carbon source, add 2 g of PEG (# 6000) and 1 g of stearic acid as molding aids, and mix them with methanol in a ball mill for 24 hours. Then, the mixed slurry was granulated by spray drying with a spray dryer to obtain a spherical granulated material having a diameter of 20 to 80 μm.
[0158]
Preliminary molding step: Using the granulated material obtained in the granulation step, a preform was obtained by the same preliminary molding step as in Comparative Example 1.
[0159]
Firing step: The preform formed in the preforming step was fired in the same firing step as in Comparative Example 1 to obtain a silicon carbide sintered material having the same shape as Comparative Example 1. This silicon carbide sintered material is the same quality as a general dense silicon carbide sintered material.
[0160]
Finishing step: The composite silicon carbide sintered material obtained in the firing step was subjected to the same finishing step as in Comparative Example 1 to obtain a sliding body B10 that could be used as the rotating ring 3.
[0161]
As shown in FIG. 1, the sliding bodies A1 to A5 of the present invention obtained as described above are composite silicon carbide structures (parts forming black in the figure) bonded to silicon carbide particles in a state where graphite particles are aggregated. ) Are independently dispersed in a dense single silicon carbide structure in which silicon carbide particles are bonded to each other, and the sliding bodies A6 to A12 are carbonized in a state where carbon black particles are aggregated as illustrated in FIG. The composite silicon carbide structure bonded to the silicon particles (the black portion in the figure) is dispersed independently in a dense single silicon carbide structure in which the silicon carbide particles are bonded to each other. As shown in FIG. 3, in a dense single silicon carbide structure in which silicon carbide particles are bonded to each other in a complex silicon carbide structure (the black portion in the figure) bonded to silicon carbide particles in a state where BN particles are aggregated. Disperse It is intended. FIG. 1 is a photomicrograph showing the mirror surface of the sliding body A1, FIG. 2 is a microscopic view showing the mirror surface of the sliding body A8, and FIG.
[0162]
On the other hand, the sliding bodies B1 to B9 contain a solid lubricant like the sliding bodies A1 to A13, but as exemplified in FIGS. 4 to 6, the graphite particles and carbon that are solid lubricants. Black particles and BN particles are not partially aggregated and are dispersed throughout the silicon carbide structure. That is, the whole sliding body B1-B9 has comprised the structure | tissue similar to said composite silicon carbide structure | tissue. In addition, as shown in FIG. 7, the sliding body 10 does not contain a solid lubricant and has a dense silicon carbide structure. 4 shows the mirror surface of the sliding body B3, FIG. 5 shows the mirror surface of the sliding body B6, FIG. 6 shows the mirror surface of the sliding body B9, and FIG. 7 enlarges the mirror surface of the sliding body B10 by 100 times. It is a microscope picture shown.
[0163]
Thus, the total lubricant content of the sliding bodies A1 to A13 (the solid lubricant content in the entire sliding body) and the local lubricant content (the solid lubricant content in each composite silicon carbide structure) are shown in Table 1. The diameter of each composite silicon carbide structure portion in the sliding bodies A1 to A13 was 20 to 50 μm. The solid lubricant content (corresponding to the overall lubricant content) in the sliding bodies B1 to B10 is as shown in Table 1. Moreover, when the density (by water displacement method) and bending strength were determined for the sliding bodies A1 to A13 and B1 to B10, they were as shown in Table 1.
[0164]
As is clear from Table 1, the density and bending strength of the sliding bodies A1 to A13 and B1 to B9 containing the solid lubricant become smaller as the solid lubricant content (total lubricant content) becomes higher. ing. However, the density and bending strength in the sliding bodies A1 to A13 are the same as that of the solid lubricant except for the sliding body B10 that does not contain the solid lubricant and the sliding body B1 in which the solid lubricant content is minimum (2%). Regardless of the rate, it is higher than the sliding bodies B2 to B9. In particular, when the solid lubricant content is the same, the density and bending strength of the sliding bodies A1 to A13, including the sliding body B1, are significantly higher than the sliding bodies B1 to B9. These things are mentioned at the beginning, but are considered to be due to the following reasons.
[0165]
That is, in the sliding bodies B1 to B9 in which the solid lubricant particles are dispersed throughout the sliding body, the bonding force between the solid lubricant particles and the silicon carbide particles is smaller than the bonding force between the silicon carbide particles, and the solid lubricant Since the presence hinders the sintering action of silicon carbide, the sintering force of the entire sliding body is reduced, and the degree of reduction becomes more prominent as the solid lubricant content increases. On the other hand, in the sliding bodies A1 to A13, since the solid lubricant particles are not dispersed throughout the sliding body, the ratio occupied by the portion where the silicon carbide particles are directly bonded (single silicon carbide structure portion) is occupied. There are many. And although the part (composite silicon carbide structure | tissue part) containing a solid lubricant has the low bond strength of silicon carbide and a solid lubricant like sliding bodies B1-B9, at the time of baking of a single silicon carbide structure | tissue part Due to the contraction action, it is strongly tightened from the outer peripheral side to the center side, and the bonding force in the composite silicon carbide structure is increased. Further, at the boundary portion between the composite silicon carbide structure and the single silicon carbide structure, the bonding action by sintering of silicon carbide particles and the bonding force increasing action by the contraction action are equivalent to those in the single silicon carbide structure. Bonding force between particles is ensured. That is, not only the interparticle bonding force in the single silicon carbide structure part, but also the interparticle bonding force in the composite silicon carbide structure part and the bonding force between both structure parts are increased. Therefore, in the sliding bodies A1 to A13, the binding force as the whole sliding body is increased, the density is improved, and the bending strength is also improved.
[0166]
In addition, the sliding bodies A1 to A13 and B1 to B10 were incorporated in the mechanical seal as the rotating ring 3, and a seal test was performed. In addition, as the fixed ring 1, the dense silicon carbide sintered material (density: 3.130 g / cm) obtained by the process similar to the case where the sliding body 10 was obtained in the comparative example 10. ^Three ) Was used.
[0167]
Thus, in this seal test, the mechanical seal was operated continuously for 2 hours under dry conditions of load pressure: 0.1 MPa and peripheral speed: 2 m / s, and the sliding surfaces (seal The wear rate (μm / Hr), the friction coefficient, and the temperature (° C.) of the end faces 1a and 3a) were determined, and the sliding surface state of the fixed seal ring 3 was determined. The determination of the sliding surface state was performed by visually observing the degree of generation of ring marks and wear powder caused by relative rotational sliding contact with the mating sealing end surface (sealing end surface 1a of the stationary ring 1). As for the annular marks, in Table 2, “X” is given to those in which an annular groove that can be clearly seen is formed, and “△” to those that are not clearly seen but are slightly scratched. The mark is marked with “○” if no ring mark is observed. As for wear powder, in Table 2, “X” is given to those with significant wear powder, and “△” is given to those with slight wear powder, and no wear powder is generated. Those that have not been marked with a “○”.
[0168]
As can be seen from Table 2, when the sliding bodies A1 to A13 are used, in any case, compared with the case where the sliding bodies B1 to B10 are used, the wear rate, the friction coefficient, and the sliding surface. The temperature value is significantly lower. Also, with respect to the sliding surface state, all of the sliding bodies B1 to B10 have noticeable ring marks or wear powder, whereas the slide bodies A2 to A10 have no ring marks or wear powder at all. In the sliding bodies A1, A11 to A13, either the ring mark or the abrasion powder is only slightly generated.
[0169]
Therefore, the sliding bodies A1 to A13 are clearly superior in sliding characteristics as compared with the sliding bodies B1 to B9 in which the solid lubricant is dispersed and the sliding body B10 that does not contain the solid lubricant. It can be said that it is suitable as a sealing ring. Moreover, when judged from the seal test results shown in Table 2, it can be said that the total lubricant content is more preferably 4 to 20%. Furthermore, when comprehensively considering the density and bending strength shown in Table 1, it can be said that it is optimal to set the total lubricant content to 4 to 10%.
[0170]
In addition, since the result of the above-mentioned seal test is about the case where the thing made from silicon carbide which does not have self-lubricating property is used as the other party sealing ring (fixed sealing ring 1), it is excellent in self-lubricating property as the other party sealing ring. It is easily assumed that a seal test result superior to the values shown in Table 2 will be obtained when a carbon product or a sliding body of the present invention is used. Therefore, in general, the constituent material of the mating seal ring is selected according to the sealing conditions (for example, the mating seal ring is a dense silicon carbide sintered material under severe sealing conditions such as dry conditions and handling slurry fluids. A seal ring made of a hard material such as a sliding member of the present invention or a sliding body of the present invention is selected, and a seal ring made of a soft material such as carbon is selected under general sealing conditions). According to the mechanical seal using this sliding body, a good sealing function can be exhibited.
[0171]
[Table 1]

[0172]
[Table 2]

[0173]
【The invention's effect】
As can be easily understood from the above description, the sliding body of the present invention can greatly improve the lubricity without impairing the inherent characteristics of silicon carbide such as wear resistance and hardness. It can be suitably used as a seal ring for a seal, a bearing member, or the like.
[0174]
Moreover, according to the manufacturing method of this invention, this sliding body can be manufactured easily.
[0175]
In addition, according to the mechanical seal of the present invention, it is possible to exert a good sealing function under any sealing condition by configuring both sealing rings or one of them with the above sliding body according to the sealing conditions. it can.
[Brief description of the drawings]
FIG. 1 is a photomicrograph showing a mirror surface of a sliding body A1 magnified 100 times.
FIG. 2 is a photomicrograph showing the mirror surface of the sliding body A8 magnified 100 times.
FIG. 3 is a photomicrograph showing the mirror surface of the sliding body A13 magnified 100 times.
FIG. 4 is a photomicrograph showing the mirror surface of the sliding body B3 magnified 100 times.
FIG. 5 is a photomicrograph showing the mirror surface of the sliding body B6 magnified 100 times.
FIG. 6 is a photomicrograph showing the mirror surface of the sliding body B9 magnified 100 times.
FIG. 7 is a photomicrograph showing the mirror surface of the sliding body B10 magnified 100 times.
FIG. 8 is a longitudinal sectional side view showing an example of an end face contact type mechanical seal.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Fixed ring, 1a ... Sealing end surface of fixed ring, 3 ... Rotary ring (sliding body), 3a ... Sealing end surface of rotary ring.

Claims (7)

A composite silicon carbide sintered material in which a composite silicon carbide structure mixed with silicon carbide particles in a state where fine solid lubricants are densely dispersed is dispersed independently in a dense single silicon carbide structure in which silicon carbide particles are bonded to each other. A sliding body characterized by comprising: The sliding body according to claim 1, wherein the content of the solid lubricant in the composite silicon carbide structure is 10 to 50%. The sliding body according to claim 1 or 2, wherein a diameter of a portion forming the composite silicon carbide structure is 20 to 50 µm. 4. The sliding body according to claim 1, wherein the content of the solid lubricant in the composite silicon carbide sintered material is 2 to 25%. A pre-granulated material obtained by granulating a composite silicon carbide sintered raw material in which fine solid lubricant is mixed and dispersed is mixed with a single silicon carbide sintered raw material not containing a solid lubricant to produce a mixed slurry. The present granulated material obtained by granulation is pressure-molded into a predetermined shape, and the pressure-molded body is fired to form a composite silicon carbide structure that is bonded to silicon carbide particles in a state where solid lubricant particles are densely packed. A method for producing a sliding body, characterized in that, independently, a composite silicon carbide sintered material dispersed in a dense single silicon carbide structure in which silicon carbide bonds to each other is obtained. The polymer auxiliary contained in the composite silicon carbide sintered raw material for adjusting the pre-granulated material is not dissolved in the solvent contained in the single silicon carbide sintered raw material. 5. A method for producing a sliding body according to 5. In the mechanical seal configured such that the two sealing rings are in sliding contact with each other, at least one of the sealing rings is configured by the sliding body according to claim 1, claim 2, claim 3 or claim 4. And mechanical seal.

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