Two-stage sliding vane and compressor

Abstract

The application provides a two-stage sliding vane and a compressor. The two-stage sliding vane comprises a first sliding vane part and a second sliding vane part; the material of the first sliding vane part is an iron-copper-based composite powder metallurgy material, raw materials of which include iron powder, copper powder, solid lubricant, tungsten carbide powder and chromium powder; the material of the second sliding vane part is a SiC-aluminum impregnated graphite composite material, which comprises aluminum-containing metal, graphite and silicon carbide, and the weight percentage of the aluminum-containing metal in the SiC-aluminum impregnated graphite composite material is less than or equal to 50%. The two-stage sliding vane has the characteristics of light weight and high strength, good wear resistance and friction reduction, and the expansion coefficient is suitable for existing compressor components, so that the friction performance requirement of the sliding vane under super-high rotating speed can be met, and the reliability and service life of the sliding vane are improved.

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and more specifically, to a two-stage vane compressor. Background Technology

[0002] As a crucial component of rotary compressors, the vane exhibits a complex friction pattern. The two large end faces at the tail of the vane reciprocate with the cylinder via inertial motion, forming a surface contact friction pair. The vane head, however, maintains close contact with the compressor's eccentric rollers, forming a line contact friction pair. Existing technologies commonly use one-piece vanes made of stainless steel or high-speed steel. During compressor operation, the vane operates under prolonged conditions of high temperature, high pressure, and high-speed impact loads. The line contact area at the vane head is often in a critical lubrication state with insufficient or no oil, experiencing the most severe load and thus being the most prone to wear.

[0003] With the continuous development of miniaturized and high-speed compressors, newer, higher-speed variable frequency drives (VFDs) require lightweight yet more wear-resistant sliding vanes to ensure the vane's "following" of the piston and its "reliability." Traditional sliding vane materials are mainly high-strength cast iron or steel, with a density of approximately 7.2 g / cm³. 3 Due to their large mass, and with increasing frequency and ultra-high speed, traditional sliding vane materials cannot keep up with the movement of the rollers, resulting in separation and producing sliding vane noise. In summary, with the continuous development of variable frequency compressors, the limitations of traditional materials have begun to emerge; they are no longer sufficient to meet the requirements of rotary compressors moving towards higher frequencies and energy efficiency.

[0004] Currently, the main solutions to the wear problem of the vane head and roller surface are to apply coatings to the vane using physical vapor deposition (PVD), atomic deposition (CVD), or plasma chemical vapor deposition (PCVD) to improve the surface hardness of the vane and thus reduce wear. However, these methods are costly, and the adhesion between the vane coating and the metal substrate is weak. Under prolonged boundary lubrication, the coating may peel off or wear away, failing to guarantee the long-term reliability of the vane. Furthermore, increased friction causes changes in vane dimensions, leading to increased leakage and reduced compressor efficiency.

[0005] To address these issues, patent CN110848138A discloses a slide with micro-dimpled structures and a friction-reducing coating on both sides. The friction-reducing coating covers the friction sides and the inner wall of the micro-dimpled structures that store lubricant. During friction, the lubricant in the micro-dimpled structures can act as a secondary replenishment source to reduce friction. However, the micro-dimpled structure requires lubricating oil to be present at the slide position within the compressor for storage. Therefore, in this invention, the micro-dimpled structure can only be designed on both sides. However, for the slide head, since this position is in contact with the roller line, it is in a critical lubrication state of insufficient or no oil for a long time. Therefore, the micro-dimples cannot store oil on the friction surface of the head, making its effect on solving the wear problem between the slide head and the rollers not significant. Patent CN109280818A discloses a wear-resistant and friction-reducing aluminum alloy material, consisting of 60% aluminum or aluminum alloy matrix, 10-30% silicon carbide particles, and 10-30% hexagonal boron nitride particles. However, due to the high linear expansion coefficient of the large proportion of aluminum alloy (23.2 × 10⁻⁶), the micro-dimpled structure is not suitable for this purpose. -6 ℃ -1 In rotary compressors, the clearance between the pump body and the sliding vanes is typically in the micrometer range, while other pump body materials are generally cast iron with an expansion coefficient of 10–12 × 10⁻⁶. -6 ℃ -1 Therefore, the linear expansion coefficient of the material in this invention cannot meet the requirements of the linear expansion coefficient of the rotary compressor vane material. Summary of the Invention

[0006] The main objective of this invention is to provide a two-stage vane and compressor to solve the problem of poor friction performance of compressor vanes in the prior art.

[0007] To achieve the above objectives, according to one aspect of the present invention, a two-section sliding plate is provided, comprising a first sliding plate portion located at the head and a second sliding plate portion located at the tail; the first sliding plate portion and the second sliding plate portion are fixedly connected; wherein, the material of the first sliding plate portion is an iron-copper based composite powder metallurgy material, the raw materials of which include iron powder, copper powder, solid lubricant, tungsten carbide powder and chromium powder; the material of the second sliding plate portion is a SiC-aluminum impregnated graphite composite material, which includes aluminum-containing metal, graphite and silicon carbide, wherein the aluminum-containing metal is aluminum and / or aluminum alloy, and the weight percentage of the aluminum-containing metal in the SiC-aluminum impregnated graphite composite material is ≤50%.

[0008] Furthermore, by weight, the raw materials for the iron-copper based composite powder metallurgy material include: 45-50 parts of iron powder, 10-15 parts of copper powder, 15-33 parts of solid lubricant, 7-10 parts of tungsten carbide powder, and 1-3 parts of chromium powder.

[0009] Further, the solid lubricant includes molybdenum disulfide powder and / or graphite powder; preferably, the solid lubricant includes 5 to 15 parts of molybdenum disulfide powder and 10 to 18 parts of graphite powder.

[0010] Furthermore, the particle size of the iron powder is 5–10 μm; and / or the particle size of the copper powder is 3–8 μm; and / or the particle size of the molybdenum disulfide powder is 80–100 nm; and / or the particle size of the graphite powder is 5–10 μm; and / or the particle size of the tungsten carbide powder is 1–5 μm; and / or the particle size of the chromium powder is 1–5 μm.

[0011] Furthermore, the iron-copper based composite powder metallurgy material has a strength ≥800MPa and a hardness of 50~55HRC after heat treatment; and / or the porosity of the iron-copper based composite powder metallurgy material is 4~8%, and the pore diameter is ≤1μm.

[0012] Further, by weight, the SiC-aluminum impregnated graphite composite material comprises: 45-50 parts aluminum metal, 18-22 parts graphite, and 33-42 parts silicon carbide; preferably, the ratio of the total weight of graphite and silicon carbide to the weight of aluminum metal is (1-1.4):1.

[0013] Furthermore, the coefficient of linear expansion of the SiC-aluminum impregnated graphite composite material is 11.5 × 10⁻⁶. -6 ℃ -1 ~12×10 -6 ℃ -1 .

[0014] Furthermore, the first sliding plate portion and the second sliding plate portion are fixedly connected by an interference fit or a snap-fit ​​method; preferably, the axial length ratio of the first sliding plate portion and the second sliding plate portion is (7.5~8.5):1.

[0015] According to another aspect of the present invention, a compressor is provided, comprising the two-section vane described above.

[0016] According to another aspect of the present invention, a refrigeration device is provided, comprising the two-section vane described above, or comprising the compressor described above.

[0017] Applying the technical solution of this invention, a two-stage vane structure is adopted to address the different friction conditions in different parts of the compressor vane. In the first vane section located at the vane head, a high-strength, high-wear-resistant iron-copper based composite powder metallurgy material is used. By optimizing the material composition, copper powder is added to the iron-based powder to improve the material's strength; a solid lubricant is used to improve the material's friction reduction properties; tungsten carbide powder is added to improve the material's hardness; and chromium powder is used to improve the material's heat treatment hardenability. The synergistic effect of these components gives the material a better porosity. Thus, while ensuring the vane head material has high strength, its porous structure allows for oil storage and drainage. In the absence of oil or dry friction conditions, it can automatically release and release oil according to the operating temperature, thereby solving the problem of easy contact wear at the vane head and significantly improving the friction performance of the vane head.

[0018] In the second sliding section located at the tail of the sliding vane, a lightweight, high-strength SiC-aluminum impregnated graphite composite material with a suitable coefficient of thermal expansion is used. SiC acts as a supporting skeleton to increase wear resistance, while the flake-like structure of graphite makes it easily adsorbed onto the part surface, providing solid lubrication and reducing friction. Combined with aluminum or aluminum alloys, it solves the problems of poor friction reduction in traditional cast steel and poor wear resistance in aluminum alloys. Simultaneously, by controlling the component ratio, the material at the tail of the sliding vane achieves a lighter weight while addressing the issue of high linear expansion coefficients in existing aluminum alloy composite materials, thereby preventing the sliding vane from detaching from the roller during ultra-high-speed operation.

[0019] In summary, the two-section sliding vane of the compressor of the present invention has good wear resistance and friction reduction properties, and its expansion coefficient is compatible with existing compressor components. It can meet the friction performance requirements of the sliding vane at ultra-high speeds, thereby improving the reliability and service life of the sliding vane. Attached Figure Description

[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 A schematic diagram of a two-segment slider structure according to an embodiment of the present invention is shown;

[0022] Figure 2 A metallographic diagram of an iron-copper based composite powder metallurgy material according to an embodiment of the present invention is shown; and

[0023] Figure 3 A metallographic diagram of a SiC-aluminum impregnated graphite composite material according to an embodiment of the present invention is shown.

[0024] The above figures include the following reference numerals:

[0025] 1. First sliding part; 11. First protrusion; 12. Second protrusion; 2. Second sliding part; 21. First concave point; 22. Second concave point. Detailed Implementation

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] As described in the background section of this invention, existing technologies suffer from problems such as easy wear on the compressor vane head and the inability to balance lightweight and thermal expansion coefficient, resulting in poor friction performance of the compressor vane. To address these issues, in a typical embodiment of this invention, a two-section vane for a compressor is provided, comprising a first vane section 1 at the head and a second vane section 2 at the tail; the first vane section 1 and the second vane section 2 are fixedly connected; wherein the material of the first vane section 1 is an iron-copper based composite powder metallurgy material, the raw materials of which include iron powder, copper powder, solid lubricant, tungsten carbide powder, and chromium powder; the material of the second vane section 2 is a SiC-aluminum impregnated graphite composite material, which includes aluminum-containing metal, graphite, and silicon carbide, wherein the aluminum-containing metal is aluminum and / or aluminum alloy, and the weight percentage of the aluminum-containing metal in the SiC-aluminum impregnated graphite composite material is ≤50%.

[0028] Existing conventional sliding pads typically involve nitriding a high-speed steel / stainless steel substrate and then coating it with DLC (diamond-like carbon) film. This process is complex and results in high costs. Furthermore, traditional sliding pads are one-piece structures using the same materials. However, the inventors unexpectedly discovered during their research that the friction patterns differ across different parts of the sliding pad. The head of the sliding pad, which is constantly in a boundary lubrication state, experiences significantly more wear than the two end faces at the tail. This area is chronically under-lubricated, resulting in a thin oil film, high friction coefficient, and significant wear. Over time, the head of the sliding pad will become worn flat, leading to changes in surface tolerances, increased leakage, reduced cooling capacity, and in severe cases, even jamming.

[0029] To this end, the slide of the present invention adopts a two-section structure and the materials of each part are specially selected. The head of the slide is made of a high-strength, high-wear-resistant iron-copper-based composite powder metallurgy material, while the tail of the slide is made of a lightweight, high-strength SiC-aluminum impregnated graphite composite material with a coefficient of expansion that is more compatible with existing compressor components.

[0030] Traditional iron-based powder metallurgy materials undergo oil impregnation to introduce a certain amount of lubricating oil into the matrix, sacrificing the material's inherent mechanical properties to achieve friction reduction. However, lubricating oil is prone to failure under certain operating conditions (such as ultra-low temperatures, high vacuum, and high speed and high load), causing a decrease or even complete loss of the material's friction-reducing and wear-resistant properties, leading to severe wear of parts. Therefore, this invention utilizes a raw material comprising iron powder, copper powder, solid lubricant, tungsten carbide powder, and chromium powder in the iron-copper based composite powder metallurgy material of the first sliding vane section 1. Copper powder is used to improve the material's strength, tungsten carbide powder to improve its hardness, and chromium powder to enhance its heat treatment hardenability. The synergistic effect of the solid lubricant and lubricating oil significantly improves the material's friction-reducing properties. Specifically, when the compressor is not operating, the lubricating oil fills the pores inherent in the material of the first sliding vane section 1. During operation, friction generates heat, causing the material to expand and reduce the pores, allowing lubricating oil to overflow and cover the first sliding vane section 1 at the vane head. When the compressor stops and cools, the material contracts, increasing the pores, and the lubricating oil re-enters the pores.

[0031] The iron-copper based composite powder metallurgy material can be prepared by mixing the above-mentioned components and then performing conventional powder metallurgy processes. This is understandable to those skilled in the art and will not be elaborated further here. A metallographic diagram of an iron-copper based composite powder metallurgy material according to a typical embodiment is shown below. Figure 2 As can be seen, the material itself has a certain porosity, which can ensure that the material of the sliding head has high strength while relying on its own porous structure to store and release oil. In the case of insufficient oil or dry friction, it can automatically release and release oil according to the operating temperature, thereby solving the problem of easy contact wear of the sliding head and greatly improving the friction performance of the sliding head.

[0032] Existing high-strength, lightweight materials mainly include aluminum alloys, magnesium alloys, and titanium alloys, among which aluminum alloys are widely used in machinery, construction, automotive, and aerospace fields. However, the pump body clearance of rotary compressors is generally in the micrometer range, requiring high thermal expansion performance; therefore, the material is typically cast iron with a thermal expansion coefficient of 10–12 × 10⁻⁶. -6 ℃ -1 The coefficient of thermal expansion of aluminum-containing metals (aluminum or aluminum alloys) is approximately 27 × 10⁻⁶. -6 ℃ -1 The significant difference in properties limits its application in rotary compressor pump bodies.

[0033] Therefore, the present invention employs a SiC-aluminum impregnated graphite composite material in the second sliding vane section 2, comprising aluminum-containing metal, graphite, and silicon carbide, wherein the aluminum-containing metal accounts for ≤50% of the weight percentage of the SiC-aluminum impregnated graphite composite material. Because the proportion of aluminum-containing metal is relatively low, while the proportions of graphite and silicon carbide are relatively high, on the one hand, using aluminum-containing metal allows the material at the tail of the sliding vane to have a lighter weight; on the other hand, the relatively low aluminum content can solve the problem of the high coefficient of linear expansion of existing aluminum alloy composite materials, thereby avoiding the sliding vane from separating from the roller and generating sliding vane noise due to the mismatch of the linear expansion coefficients between the sliding vane and other compressor components during ultra-high-speed operation.

[0034] Meanwhile, graphite is precipitated during the operation of the compressor. Graphite has adsorption properties, and the precipitated graphite can be adsorbed onto the surface of the rotary compressor components. Its unique hexagonal crystal structure has low interlayer bonding force, and it is easy to undergo interlayer slippage under the action of tangential force, thereby playing a good solid lubrication role. This can reduce the friction coefficient of the sliding friction surface between the second vane part 2 and the cylinder vane groove, and reduce wear.

[0035] Furthermore, to improve the strength of the second sliding part 2, a reinforcing phase needs to be added to the graphite-impregnated aluminum base to enhance the material strength. Existing reinforcing phases include aluminum oxide and silicon carbide. Considering the stringent requirements of the linear expansion coefficient for the material of the second sliding part 2, this invention adopts a thermal expansion coefficient of 4 to 6 × 10⁻⁶. -6 ℃ -1 SiC, as the fibrous skeleton of SiC-aluminum impregnated graphite composites, has a coefficient of thermal expansion of approximately 27 × 10⁻⁶. -6 ℃ -1 Aluminum-containing metals have a coefficient of thermal expansion of approximately 6 × 10⁻⁶. -6 ℃ -1 The graphite is combined with the second sliding part 2 to achieve the purpose of being lightweight, high-strength, and having a suitable coefficient of thermal expansion.

[0036] The SiC-aluminum impregnated graphite composite material is prepared by impregnating aluminum-containing metal in graphite and then mixing it with SiC. This is readily understood by those skilled in the art and will not be elaborated further here. A metallographic diagram of a typical embodiment of the SiC-aluminum impregnated graphite composite material is shown below. Figure 3 As can be seen, the graphite is precipitated in flake form, and the SiC fibers are evenly distributed in the material as a skeleton to provide strength support.

[0037] In a preferred embodiment, the raw materials of the iron-copper based composite powder metallurgy material, by weight, include: 45-50 parts of iron powder, 10-15 parts of copper powder, 15-33 parts of solid lubricant, 7-10 parts of tungsten carbide powder, and 1-3 parts of chromium powder. The above components can enable the iron-copper based composite powder metallurgy material to have better porosity and strength properties, thereby better meeting the requirements of wear resistance and friction reduction of the sliding head.

[0038] In order to further improve the synergistic lubrication effect of solid lubricant and lubricating oil, in a preferred embodiment, the solid lubricant includes molybdenum disulfide powder and / or graphite powder; preferably, the solid lubricant includes 5 to 15 parts of molybdenum disulfide powder and 10 to 18 parts of graphite powder. The above solid lubricant can better improve the friction reduction of iron-copper based composite powder metallurgy materials.

[0039] To further improve the microstructure uniformity of iron-copper based composite powder metallurgy materials, in a preferred embodiment, the particle size of iron powder is 5-10 μm; and / or the particle size of copper powder is 3-8 μm; and / or the particle size of molybdenum disulfide powder is 80-100 nm; and / or the particle size of graphite powder is 5-10 μm; and / or the particle size of tungsten carbide powder is 1-5 μm; and / or the particle size of chromium powder is 1-5 μm.

[0040] To further improve the strength of the material, the iron-copper based composite powder metallurgy material can be subjected to heat treatment. The heat treatment is not limited to conventional quenching, tempering, normalizing and other methods in this field. At the same time, due to the addition of chromium powder in the iron-copper based composite powder metallurgy material, the hardenability of the material after heat treatment can be greatly improved. Therefore, in a preferred embodiment, the iron-copper based composite powder metallurgy material can achieve a strength of ≥800MPa and a hardness of 50-55HRC (Rockwell hardness) after heat treatment, which can better meet the high strength and high wear resistance friction performance requirements of the slider head.

[0041] During their research, the inventors unexpectedly discovered that if the porosity of the iron-copper-based composite powder metallurgy material is too high, the poor continuity of the microstructure will lead to a decrease in material strength; if the porosity is too low, the oil retention effect will be poor, and the friction reduction performance of the material will be greatly reduced. Therefore, in a preferred embodiment, the porosity of the iron-copper-based composite powder metallurgy material with a specific composition can be conveniently controlled at 4-8% and the pore diameter ≤1μm by controlling the powder metallurgy process (such as pressing parameters and other control methods well known to those skilled in the art). This can better meet the friction performance requirements of the sliding head automatically feeding and discharging oil according to the operating temperature and reducing contact wear.

[0042] In a preferred embodiment, the SiC-aluminum impregnated graphite composite material comprises, by weight, 45-50 parts aluminum metal, 18-22 parts graphite, and 33-42 parts silicon carbide. This composition allows the SiC-aluminum impregnated graphite composite material to possess better quality and strength properties, thereby better balancing the requirements of lightweight, high-strength, wear-resistant, and suitable coefficient of thermal expansion for the sliding tail section.

[0043] In order to make the SiC-aluminum impregnated graphite composite material have a lighter weight and higher strength, while making its coefficient of thermal expansion more compatible with the compressor components, in a preferred embodiment, the ratio of the total weight of graphite and silicon carbide to the weight of aluminum-containing metal is (1 to 1.4):1.

[0044] In a preferred embodiment, the coefficient of linear expansion of the SiC-aluminum impregnated graphite composite material is 11.5–12 × 10⁻⁶. -6 ℃ -1 It can be used with compressor components (generally cast iron, with a coefficient of thermal expansion of 10 to 12 × 10⁻⁶). -6 ℃ -1 The coefficient of thermal expansion is more suitable, meeting the requirements of the sliding tail for thermal expansion performance.

[0045] In a preferred embodiment, the first sliding plate portion 1 and the second sliding plate portion 2 are fixedly connected by an interference fit or a snap-fit ​​method. There can be one or more connection points between the first sliding plate portion 1 and the second sliding plate portion 2. When an interference fit is used, the second sliding plate portion 2 accommodates the first sliding plate portion 1. These details are understandable to those skilled in the art based on this invention and will not be elaborated further here. In a typical embodiment, such as... Figure 1 As shown, the first slider part 1 has a first protrusion 11 and a second protrusion 12, and the second slider part 2 has a first concave point 21 and a second concave point 22. The first protrusion 11 and the first concave point 21, and the second protrusion 12 and the second concave point 22 are in one-to-one contact and interlock, thereby realizing the fixed connection between the first slider part 1 and the second slider part 2.

[0046] The axial length ratio of the first sliding plate part 1 and the second sliding plate part 2 can be flexibly adjusted according to different application scenarios. Preferably, the axial length ratio of the first sliding plate part 1 and the second sliding plate part 2 is (7.5~8.5):1. This allows for better high strength and wear resistance at the head end, while ensuring lightweight and thermal expansion coefficient compatibility at the tail end, thereby achieving the goal of comprehensively improving the friction performance of the sliding plate.

[0047] In another typical embodiment of the present invention, a compressor is also provided, preferably a rotary compressor, including the two-stage vane described above, which can take into account light weight, high strength, good wear resistance and friction reduction, better friction performance and reliability, and can improve energy efficiency, meeting the requirements of compressors to develop towards higher frequency and energy saving.

[0048] In another typical embodiment of the present invention, a refrigeration device is also provided, including the two-stage vane or the compressor described above. The refrigeration device has all the beneficial effects of the two-stage vane or compressor provided by any of the above technical solutions.

[0049] Typical, but not limited, iron-copper based composite powder metallurgy materials, by weight, include: 45, 46, 47, 48, 49, or 50 parts of iron powder or any two of these values; 10, 11, 12, 13, 14, or 15 parts of copper powder or any two of these values; 15, 20, 25, 30, or 33 parts of solid lubricant or any two of these values; 7, 8, 9, or 10 parts of tungsten carbide powder or any two of these values; and 1, 2, or 3 parts of chromium powder or any two of these values.

[0050] Typical, but not limiting, solid lubricants in iron-copper based composite powder metallurgy materials, by weight, include: 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts of molybdenum disulfide powder or any two of these values; and 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts of graphite powder or any two of these values.

[0051] Typical, but not limiting, iron-copper based composite powder metallurgy materials may contain iron powder with a particle size of 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, or any combination of two such values; and / or copper powder with a particle size of 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, or any combination of two such values; and / or molybdenum disulfide powder with a particle size of 80 nm, 85 nm, 90 nm, 95 nm, 100 nm. m or any two of the following values; and / or the particle size of the graphite powder is 5μm, 6μm, 7μm, 8μm, 9μm, 10μm or any two of the following values; and / or the particle size of the tungsten carbide powder is 1μm, 2μm, 3μm, 4μm, 5μm or any two of the following values; and / or the particle size of the chromium powder is 1μm, 2μm, 3μm, 4μm, 5μm or any two of the following values.

[0052] Typical, but not limiting, iron-copper based composite powder metallurgy materials have porosities of 4%, 5%, 6%, 7%, 8%, or any two of these values.

[0053] Typical, but not limited, SiC-aluminum impregnated graphite composites include: 45, 46, 47, 48, 49, 50 parts of aluminum or aluminum alloy, or any two of these values; 18, 19, 20, 21, 22 parts of graphite, or any two of these values; and 33, 34, 35, 36, 37, 38, 39, 40, 41, 42 parts of silicon carbide, or any two of these values.

[0054] Typical, but not limiting, SiC-aluminum impregnated graphite composites have a total weight ratio of graphite and silicon carbide to aluminum metal of 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, or any two of these ratios within a range.

[0055] A typical, but not limiting, coefficient of linear expansion for SiC-aluminum impregnated graphite composites is 11.5 × 10⁻⁶. -6 ℃ -1 11.6×10 -6 ℃ -1 11.7×10 -6 ℃ -1 11.8×10 -6 ℃ -1 11.9×10 -6 ℃ -1 12×10 -6 ℃ -1 Or a range of values ​​consisting of any two of its values.

[0056] Typically, but not limitingly, the axial length ratio of the first sliding portion 1 and the second sliding portion 2 is 7.5:1, 7.6:1, 7.7:1, 7.8:1, 7.9:1, 8.0:1, 8.1:1, 8.2:1, 8.3:1, 8.4:1, 8.5:1, or any two of these ratios.

[0057] The present application will be further described in detail below with reference to specific embodiments, which should not be construed as limiting the scope of protection claimed in the present application.

[0058] The following embodiments and comparative examples show schematic diagrams of the two-segment slider structure. Figure 1 The first sliding portion 1 has a first protrusion 11 and a second protrusion 12, and the second sliding portion 2 has a first concave point 21 and a second concave point 22. The first protrusion 11 and the first concave point 21, and the second protrusion 12 and the second concave point 22, are in a one-to-one contact fit to achieve the connection between the first sliding portion 1 and the second sliding portion 2. The axial length ratio of the first sliding portion 1 and the second sliding portion 2 is 8:1.

[0059] Example 1

[0060] The first sliding plate part 1 is made of iron-copper based composite powder metallurgy material with the following composition: 50 parts iron powder (8μm particle size), 15 parts copper powder (6μm particle size), 10 parts molybdenum disulfide powder (90nm particle size), 15 parts graphite powder (8μm particle size), 7 parts tungsten carbide powder (3μm particle size), and 3 parts chromium powder (3μm particle size). A standard friction specimen was prepared using a universal friction testing machine (manufacturer: Jinan Yihua, model MMW-1A). After heat treatment, the specimen has a strength of 821MPa, a hardness of 52HRC, a porosity of 5%, and a pore diameter ≤1μm. The friction coefficient was tested using a universal friction testing machine with a load of 200N, a rotation speed of 1000r / min, and a time of 60min, against FC300 cast iron material. The metallographic structure of the iron-copper based composite powder metallurgy material is shown below. Figure 2 .

[0061] The second sliding section 2 is a SiC-aluminum impregnated graphite composite material composed of 48 parts aluminum alloy, 21 parts graphite, and 35 parts silicon carbide. A standard sample of Φ6×25mm was prepared using a thermal expansion meter (Netzsch, Germany, model DIL 402Expedis Classic). The coefficient of thermal expansion was tested using the thermal expansion meter at a temperature of 20–200℃ and a heating rate of 2℃ / s. Since the compressor's operating limit temperature is approximately 150℃, the coefficient of thermal expansion at 150℃ was the primary test value. The metallographic structure of the SiC-aluminum impregnated graphite composite material is shown below. Figure 3 .

[0062] Example 2

[0063] The first sliding plate part 1 is made of iron-copper based composite powder metallurgy material with the following composition: 50 parts iron powder (8μm particle size), 15 parts copper powder (6μm particle size), 10 parts molybdenum disulfide powder (90nm particle size), 15 parts graphite powder (8μm particle size), 7 parts tungsten carbide powder (3μm particle size), and 3 parts chromium powder (3μm particle size). A standard friction specimen for a universal friction testing machine is prepared. After heat treatment, the specimen has a strength of 821MPa, a hardness of 52HRC, a porosity of 5%, and a pore diameter ≤1μm. The coefficient of friction is tested using a universal friction testing machine with a load of 200N, a rotation speed of 1000r / min, and a time of 60min, against FC300 cast iron material.

[0064] The second sliding vane section 2 is made of SiC-aluminum impregnated graphite composite material: 45 parts aluminum alloy, 15 parts graphite, and 40 parts silicon carbide. A standard sample with a diameter of Φ6×25mm was prepared using a thermal expansion meter to test the coefficient of thermal expansion. The test temperature ranged from 20 to 200℃, with a heating rate of 2℃ / s. Since the compressor's operating temperature limit is approximately 150℃, the coefficient of thermal expansion of the material at 150℃ was the primary test parameter.

[0065] Example 3

[0066] The first sliding plate part 1 is made of iron-copper based composite powder metallurgy material with the following composition: 48 parts iron powder (8μm particle size), 13 parts copper powder (6μm particle size), 10 parts molybdenum disulfide powder (90nm particle size), 14 parts graphite powder (8μm particle size), 9 parts tungsten carbide powder (3μm particle size), and 2 parts chromium powder (3μm particle size). A standard friction specimen for a universal friction testing machine was prepared. After heat treatment, the specimen had a strength of 823MPa, a hardness of 55HRC, a porosity of 6%, and a pore diameter ≤1μm. The coefficient of friction was tested using a universal friction testing machine with a load of 200N, a rotation speed of 1000r / min, and a time of 60min, against FC300 cast iron material.

[0067] The second sliding vane section 2 is made of SiC-aluminum impregnated graphite composite material: 48 parts aluminum alloy, 20 parts graphite, and 38 parts silicon carbide. A standard sample with a diameter of Φ6×25mm was prepared using a thermal expansion meter. The coefficient of thermal expansion was tested using the thermal expansion meter at a temperature of 20–200℃ and a heating rate of 2℃ / s. Since the compressor's operating temperature limit is approximately 150℃, the coefficient of thermal expansion of the material at 150℃ was the primary test parameter.

[0068] Examples 4 to 15

[0069] The difference between Examples 4 to 15 and Example 1 is that the composition of the iron-copper based composite powder metallurgy material in the first sliding part 1 is different, as detailed in Table 1.

[0070] Examples 16 to 21

[0071] The difference between Examples 16 to 21 and Example 1 is that the SiC-aluminum impregnated graphite composite material of the second sliding part 2 has a different composition, as detailed in Table 2.

[0072] Example 22

[0073] The first sliding plate part 1 is made of iron-copper based composite powder metallurgy material with the following composition: 45 parts iron powder (5μm particle size), 15 parts copper powder (3μm particle size), 5 parts molybdenum disulfide powder (80nm particle size), 18 parts graphite powder (10μm particle size), 7 parts tungsten carbide powder (1μm particle size), and 1 part chromium powder (1μm particle size). A standard friction specimen for a universal friction testing machine is prepared, with a strength of 805MPa, a hardness of 51HRC, a porosity of 4%, and a pore diameter ≤1μm after heat treatment. The coefficient of friction is tested using a universal friction testing machine with a load of 200N, a rotation speed of 1000r / min, and a time of 60min, against FC300 cast iron material.

[0074] The second sliding vane section 2 is made of SiC-aluminum impregnated graphite composite material: 50 parts aluminum alloy, 18 parts graphite, and 33 parts silicon carbide. A standard sample with a diameter of Φ6×25mm was prepared using a thermal expansion meter. The coefficient of thermal expansion was tested using the thermal expansion meter at a temperature of 20–200℃ and a heating rate of 2℃ / s. Since the compressor's operating temperature limit is approximately 150℃, the coefficient of thermal expansion of the material at 150℃ was the primary test parameter.

[0075] Example 23

[0076] The first sliding plate part 1 is made of iron-copper based composite powder metallurgy material with the following composition: 50 parts iron powder (particle size 10μm), 10 parts copper powder (particle size 8μm), 15 parts molybdenum disulfide powder (particle size 100nm), 10 parts graphite powder (particle size 5μm), 10 parts tungsten carbide powder (particle size 5μm), and 3 parts chromium powder (particle size 5μm). A standard friction specimen for a universal friction testing machine is prepared. After heat treatment, the specimen has a strength of 801MPa, a hardness of 50HRC, a porosity of 8%, and a pore diameter ≤1μm. The coefficient of friction is tested using a universal friction testing machine with a load of 200N, a rotation speed of 1000r / min, and a time of 60min, against FC300 cast iron material.

[0077] The second sliding vane section 2 is made of SiC-aluminum impregnated graphite composite material: 45 parts aluminum alloy, 22 parts graphite, and 42 parts silicon carbide. A standard sample with a diameter of Φ6×25mm was prepared using a thermal expansion meter. The coefficient of thermal expansion was tested using the thermal expansion meter at a temperature of 20–200℃ and a heating rate of 2℃ / s. Since the compressor's operating temperature limit is approximately 150℃, the coefficient of thermal expansion of the material at 150℃ was the primary test parameter.

[0078] Comparative Example 1

[0079] The first sliding plate part 1 is made of iron-copper based composite powder metallurgy material with the following composition: 60 parts iron powder, 8 parts copper powder, 10 parts molybdenum disulfide powder, 15 parts graphite powder, 6 parts tungsten carbide powder, and 1 part chromium powder. A standard friction sample for a universal friction testing machine is prepared, and after heat treatment, the hardness is 47 HRC and the porosity is 8%. The coefficient of friction is tested using a universal friction testing machine with a load of 200 N, a rotation speed of 1000 r / min, and a time of 60 min, against FC300 cast iron material.

[0080] Comparative Example 2

[0081] The first sliding plate section 1 is made of iron-copper based composite powder metallurgy material with the following composition: 55 parts iron powder, 10 parts copper powder, 15 parts molybdenum disulfide powder, 15 parts graphite powder, 5 parts tungsten carbide powder, and 3 parts chromium powder. A standard friction specimen for a universal friction testing machine is prepared, and after heat treatment, the hardness is 50 HRC and the porosity is 10%. The coefficient of friction is tested using a universal friction testing machine with a load of 200 N, a rotation speed of 1000 r / min, and a time of 60 min, against FC300 cast iron material.

[0082] Comparative Example 3

[0083] The second sliding vane section 2 is made of SiC-aluminum impregnated graphite composite material: 40 parts aluminum alloy, 30 parts graphite, and 30 parts silicon carbide. A standard sample with a diameter of Φ6×25mm was prepared using a thermal expansion meter. The coefficient of thermal expansion was tested using the thermal expansion meter at a temperature of 20–200℃ and a heating rate of 2℃ / s. Since the compressor's operating temperature limit is approximately 150℃, the coefficient of thermal expansion of the material at 150℃ was the primary test parameter.

[0084] Comparative Example 4

[0085] The second sliding vane section 2 is made of SiC-aluminum impregnated graphite composite material: 55 parts aluminum alloy, 15 parts graphite, and 30 parts silicon carbide. A standard sample with a diameter of Φ6×25mm was prepared using a thermal expansion meter. The coefficient of thermal expansion was tested using the thermal expansion meter at a temperature of 20–200℃ and a heating rate of 2℃ / s. Since the compressor's operating temperature limit is approximately 150℃, the coefficient of thermal expansion of the material at 150℃ was the primary test parameter.

[0086] Comparative Example 5

[0087] The second sliding vane section 2 is made of SiC-aluminum impregnated graphite composite material: 55 parts aluminum alloy, 25 parts graphite, and 20 parts silicon carbide. A standard sample with a diameter of Φ6×25mm was prepared using a thermal expansion meter to test the coefficient of thermal expansion. The test temperature ranged from 20 to 200℃, with a heating rate of 2℃ / s. Since the compressor's operating temperature limit is approximately 150℃, the coefficient of thermal expansion of the material at 150℃ was the primary test parameter.

[0088] The friction coefficients of the first sliding part 1 (iron-copper based composite powder metallurgy material and stainless steel nitriding material) under oil-deficient conditions and the thermal expansion coefficient of the second sliding part 2 (SiC-aluminum impregnated graphite composite material) at 150°C are shown in Table 3.

[0089] Table 1

[0090]

[0091] Table 2

[0092]

[0093]

[0094] Table 3

[0095]

[0096]

[0097] As can be seen from the above, compared with the conventionally used stainless steel nitriding material, the embodiments of the present invention adopt a two-stage sliding vane structure for different friction conditions of different parts of the compressor sliding vane. In the first sliding vane part located at the vane head, a high-strength, high-wear-resistant iron-copper-based composite powder metallurgy material is used, which has better porosity. Thus, while ensuring that the sliding vane head material has high strength, it can rely on its own porous structure to store and release oil. In the case of insufficient oil or dry friction, it can automatically release and release oil according to the operating temperature, thereby solving the problem of easy contact wear of the sliding vane head and greatly improving the friction performance of the sliding vane head.

[0098] In the second sliding vane section located at the tail end, a lightweight, high-strength SiC-aluminum impregnated graphite composite material with a thermal expansion coefficient compatible with the material is used. This allows the tail end material to have a lighter weight and good wear resistance and friction reduction properties, while solving the problem of the high linear expansion coefficient of existing aluminum alloy composite materials, thereby preventing the sliding vane from separating from the roller during ultra-high-speed operation. In summary, the two-stage sliding vane in each embodiment of the present invention has good overall wear resistance and friction reduction properties, and its expansion coefficient is compatible with existing compressor components, which can meet the friction performance requirements of the sliding vane at ultra-high speeds, improving the reliability and service life of the sliding vane. Furthermore, it can be seen that the friction performance of the material is optimal when the composition and characteristic parameters of each material are within the preferred range of the present invention.

[0099] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A two-stage slider, characterized in that, It includes a first sliding plate (1) located at the head and a second sliding plate (2) located at the tail; the first sliding plate (1) and the second sliding plate (2) are fixedly connected; wherein, The material of the first sliding plate part (1) is an iron-copper based composite powder metallurgy material. By weight, the raw materials of the iron-copper based composite powder metallurgy material include: 45-50 parts of iron powder, 10-15 parts of copper powder, 15-33 parts of solid lubricant, 7-10 parts of tungsten carbide powder, and 1-3 parts of chromium powder. The material of the second sliding part (2) is SiC-aluminum impregnated graphite composite material, which includes aluminum-containing metal, graphite and silicon carbide. The aluminum-containing metal is aluminum and / or aluminum alloy, and the weight percentage of the aluminum-containing metal in the SiC-aluminum impregnated graphite composite material is ≤50%. The coefficient of linear expansion of the SiC-aluminum impregnated graphite composite material is 11.5×10⁻⁶. -6 ℃ -1 ~12×10 -6 ℃ -1 .

2. The two-segment slider according to claim 1, characterized in that, The solid lubricant includes molybdenum disulfide powder and / or graphite powder.

3. The two-segment slider according to claim 2, characterized in that, The solid lubricant comprises: 5-15 parts of the molybdenum disulfide powder and 10-18 parts of the graphite powder.

4. The two-segment slider according to claim 2, characterized in that, The iron powder has a particle size of 5-10 μm; and / or the copper powder has a particle size of 3-8 μm; and / or the molybdenum disulfide powder has a particle size of 80-100 nm; and / or the graphite powder has a particle size of 5-10 μm; and / or the tungsten carbide powder has a particle size of 1-5 μm; and / or the chromium powder has a particle size of 1-5 μm.

5. The two-segment slider according to any one of claims 1 to 4, characterized in that, The iron-copper based composite powder metallurgy material, after heat treatment, has a strength ≥800MPa and a hardness of 50~55HRC; and / or The porosity of the iron-copper based composite powder metallurgy material is 4~8%, and the pore diameter is ≤1μm.

6. The two-segment slider according to any one of claims 1 to 4, characterized in that, The SiC-aluminum impregnated graphite composite material comprises, by weight, 45-50 parts of aluminum metal, 18-22 parts of graphite, and 33-42 parts of silicon carbide.

7. The two-segment slider according to claim 6, characterized in that, The ratio of the total weight of the graphite and the silicon carbide to the weight of the aluminum-containing metal is (1~1.4):

1.

8. The two-segment slider according to any one of claims 1 to 4, characterized in that, The first sliding plate (1) and the second sliding plate (2) are fixedly connected by an interference fit or a snap-fit ​​method.

9. The two-segment slider according to claim 8, characterized in that, The axial length ratio of the first sliding part (1) and the second sliding part (2) is (7.5~8.5):

1.

10. A compressor, characterized in that, Includes the two-segment slider as described in any one of claims 1 to 9.

11. A refrigeration device, characterized in that, It includes the two-stage vane as described in any one of claims 1 to 9, or the compressor as described in claim 10.

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