Chain accessory steel with high wear resistance and impact resistance and preparation method thereof

Abstract

The invention relates to the technical field of steel, and provides high-wear-resistance and impact-resistance chain accessory steel and a preparation method thereof.The chain accessory steel comprises a base body and a reinforcing phase, and the base body is composed of C, Mn, V, Nb, Sr, W, Cu, Al, Dy, B, Co, Tb, P, S and the balance iron and inevitable impurities; the reinforcing phase is MoC; the mass ratio of the matrix to the reinforced phase is 110: (3-6). According to the technical scheme, the problems of poor wear resistance and poor impact resistance of chain accessory steel in the prior art are solved.

Description

Technical Field

[0001] The invention relates to the technical field of steel materials, and in particular to a highly wear-resistant and impact-resistant chain accessory steel and a preparation method thereof. Background Art

[0002] Chain accessory steel is steel used to manufacture chains and their various accessories. Chains play a key role in many mechanical equipment and transmission systems, and the quality of their accessories directly affects the performance and service life of the chain. These steels undergo special smelting, processing and heat treatment processes to meet the chain's requirements for strength, wear resistance, impact resistance and other properties in different working environments.

[0003] There is relative movement between the various parts of the chain, such as between the links, between the chain pins and the link holes, between the rollers and the sprockets, etc., and these parts are prone to friction and wear. For example, in a bicycle chain, the links and rollers are constantly rubbing during the meshing process with the sprockets, so the chain accessory steel is required to have good wear resistance. Furthermore, under some working conditions, the chain may be subjected to sudden impact force. For example, in the transmission chain of a motorcycle, when the motorcycle accelerates, decelerates or encounters bumpy road conditions, the chain will be subjected to impact force. At this time, the chain accessory steel needs to be able to withstand this impact without breaking, which requires the steel to have good toughness and impact resistance. However, although the current chain accessory steel has certain wear resistance and impact resistance, its wear resistance and impact resistance are relatively limited, especially in harsh environments such as heavy loads, high speeds or major impact loads, its wear resistance and impact resistance may not meet the needs of long-term use.

[0004] Therefore, improving the wear resistance and impact resistance of chain accessory steel is a technical problem that urgently needs to be solved. Summary of the invention

[0005] The invention provides a highly wear-resistant and impact-resistant chain accessory steel and a preparation method thereof, which solves the problem of poor wear resistance and poor impact resistance of the chain accessory steel in the related art.

[0006] The technical solution of the present invention is as follows: The present invention provides a highly wear-resistant and impact-resistant chain accessory steel, comprising a matrix and a reinforcement phase, wherein the matrix is ​​composed of the following components in percentage by mass: C 0.19%~0.24%, Mn 0.85%~1.25%, V 0.03%~0.1%, Nb 0.03%~0.05%, Sr 0.005%~0.035%, W 0.04%~0.085%, Cu 0.05%~0.09%, Al 0.09%~0.15%, Dy 0.005%~0.025%, B 0.002%~0.009%, Co 0.015%~0.33%, Tb 0.0018%~0.0092%, P≤0.012%, S≤0.009%, and the rest are iron and its inevitable impurities; the reinforcing phase is MoC; The mass ratio of the matrix to the reinforcement phase is 110:3-6.

[0007] As a further technical solution, the mass ratio of the sum of the mass percentages of Sr and Dy to the mass ratio of Co is 1:2-5.

[0008] When the mass percentage of the sum of Sr and Dy to the mass ratio of Co is 1:2~5, the wear resistance and impact resistance of the chain accessory steel can be further improved by adjusting the addition amount of the three.

[0009] As a further technical solution, the MoC is modified MoC, and the raw materials of the modified MoC include MoC, vanadium powder and boron powder.

[0010] Using vanadium powder and boron powder to modify MoC simultaneously can make the reinforcement phase better infiltrate into the matrix and improve the interface bonding with the matrix, so as to form a more dense and stable chain accessory steel, thereby further improving the wear resistance and impact resistance of the chain accessory steel.

[0011] As a further technical solution, the mass ratio of the MoC, vanadium powder and boron powder is 80:2:1-4.

[0012] When the mass ratio of MoC, vanadium powder and boron powder is 80:2:1-4, the wear resistance and impact resistance of chain accessory steel can be further improved.

[0013] As a further technical solution, the preparation method of the modified MoC comprises the following steps: dry mixing the MoC, the vanadium powder and the boron powder, press-forming, sintering and crushing to obtain the modified MoC.

[0014] As a further technical solution, during the dry mixing, the rotation speed is 100-200 rpm and the time is 9-13 hours; during the sintering, the temperature is 1500-1600° C. and the time is 3-4 hours.

[0015] The present invention also proposes a method for preparing the highly wear-resistant and impact-resistant chain accessory steel, comprising the following steps: S1. Weighing the components according to the mass percentage of the matrix, blending, smelting, and obtaining molten steel; S2, refining the molten steel, adding a reinforcing phase, continuously casting, heating, and rolling to obtain a steel billet for chain accessories; S3. heat treating the chain accessory steel billet to obtain the chain accessory steel.

[0016] As a further technical solution, in step S2, the median particle size of the reinforcement phase is 20-50 μm.

[0017] As a further technical solution, in step S3, the heat treatment is divided into a first stage heat treatment, a second stage heat treatment and a third stage heat treatment. In the first stage heat treatment, the temperature is raised to 1050-1150°C, the heat preservation time is 0.5-1.5 hours, and the temperature is cooled to room temperature; in the second stage heat treatment, the temperature is raised to 650-800°C, the heat preservation time is 1-2 hours, and the temperature is cooled to room temperature; in the third stage heat treatment, the temperature is raised to 400-480°C, the temperature is kept for 2-3 hours, and the temperature is cooled to room temperature.

[0018] As a further technical solution, during the first stage heat treatment and the second stage heat treatment, the heating rate is independently 10-40°C / min; during the third stage heat treatment, the heating rate is 25-60°C / min.

[0019] As a further technical solution, the heating rates of the first stage heat treatment and the third stage heat treatment are independently greater than the heating rate of the third stage heat treatment.

[0020] When the heating rates of the first heat treatment and the third heat treatment are independently greater than the heating rate of the third heat treatment, the wear resistance and impact resistance of the chain accessory steel can be further improved.

[0021] The working principle and beneficial effects of the present invention are: In the present invention, the chain accessory steel includes a matrix and a reinforcement phase. Through the effective action of various elements in the matrix and the reinforcement phase, a chain accessory steel with good wear resistance and impact resistance can be prepared. Among them, Sr, Dy and Co are added to the matrix. Through the combined use of the three, the organizational structure of the chain accessory steel can be improved, the crystals can be refined, and thus the chain accessory steel with a stable and uniform internal structure is formed, which significantly improves the wear resistance and impact resistance of the chain accessory steel. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the following embodiments and comparative examples, the Mn content in the ferromanganese alloy is 75wt%; the V content in the vanadium-iron alloy is 50wt%; the Nb content in the niobium-iron alloy is 65wt%; the Sr content in the aluminum-strontium alloy is 30wt%; the W content in the tungsten-iron alloy is 80wt%; the copper content in the copper-iron alloy is 90wt%; the Al content in the aluminum ingot is 99.7wt%; the Tb content in the terbium-dysprosium-iron alloy is 26.6wt%, and the Dy content is 72.1wt%; the Dy content in the dysprosium-iron alloy is 85wt%; the Co content in the cobalt powder is 99.99wt%; and the Fe content in the scrap steel is 97.3wt%.

[0024] Example 1 A highly wear-resistant and impact-resistant chain accessory steel comprises a matrix and a reinforcement phase, wherein the matrix is ​​composed of the following components in percentage by mass: C 0.19%, Mn 0.85%, V 0.03%, Nb 0.03%, Sr 0.005%, W 0.04%, Cu 0.05%, Al0.09%, Dy 0.005%, B 0.002%, Co 0.015%, Tb 0.0018%, P 0.004%, S 0.002%, the rest are iron and its inevitable impurities; the reinforcement phase is MoC; The preparation method thereof comprises the following steps: S1. According to the mass percentage of the matrix, iron-manganese alloy, ferrovanadium alloy, ferroniobium alloy, aluminum-strontium alloy, ferrotungsten alloy, copper-iron alloy, aluminum ingot, terbium-dysprosium-iron alloy, dysprosium-iron alloy, cobalt powder and scrap steel are weighed, mixed and smelted to obtain molten steel; S2, refining the molten steel, adding a reinforcing phase, continuously casting, heating, and rolling to obtain a steel billet for chain accessories; Among them, the reinforcement phase is MoC, and the mass ratio of matrix and reinforcement phase is 110:3; S3. Heat the chain accessory steel billet to 1050°C at a heating rate of 10°C / min, keep it warm for 1.5 hours, and then cool it to room temperature; heat it to 650°C at a heating rate of 10°C / min, keep it warm for 2 hours, and then cool it to room temperature; heat it to 400°C at a heating rate of 25°C / min, keep it warm for 3 hours, and then cool it to room temperature to obtain chain accessory steel.

[0025] Example 2 A highly wear-resistant and impact-resistant chain accessory steel comprises a matrix and a reinforcement phase, wherein the matrix is ​​composed of the following components in percentage by mass: C 0.22%, Mn 1.1%, V 0.07%, Nb 0.04%, Sr 0.023%, W 0.06%, Cu 0.07%, Al 0.12%, Dy 0.023%, B 0.006%, Co 0.074%, Tb 0.0085%, P 0.008%, S 0.006%, the rest are iron and its inevitable impurities; the reinforcement phase is MoC; The preparation method thereof comprises the following steps: S1. According to the mass percentage of the matrix, iron-manganese alloy, ferrovanadium alloy, ferroniobium alloy, aluminum-strontium alloy, ferrotungsten alloy, copper-iron alloy, aluminum ingot, terbium-dysprosium-iron alloy, dysprosium-iron alloy, cobalt powder and scrap steel are weighed, mixed and smelted to obtain molten steel; S2, refining the molten steel, adding a reinforcing phase, continuously casting, heating, and rolling to obtain a steel billet for chain accessories; Among them, the reinforcement phase is MoC, and the mass ratio of matrix and reinforcement phase is 110:4.5; S3. Heat the chain accessory steel billet to 1100°C at a heating rate of 30°C / min, keep it warm for 1 hour, and then cool it to room temperature; heat it to 750°C at a heating rate of 30°C / min, keep it warm for 1.5 hours, and then cool it to room temperature; heat it to 440°C at a heating rate of 30°C / min, keep it warm for 2.5 hours, and then cool it to room temperature to obtain chain accessory steel.

[0026] Example 3 A highly wear-resistant and impact-resistant chain accessory steel comprises a matrix and a reinforcement phase, wherein the matrix is ​​composed of the following components in percentage by mass: C 0.24%, Mn 1.25%, V 0.1%, Nb 0.05%, Sr 0.035%, W 0.085%, Cu 0.09%, Al 0.15%, Dy 0.025%, B 0.009%, Co 0.33%, Tb 0.0092%, P 0.012%, S 0.009%, the rest are iron and its inevitable impurities; the reinforcement phase is MoC; The preparation method thereof comprises the following steps: S1. According to the mass percentage of the matrix, iron-manganese alloy, ferrovanadium alloy, ferroniobium alloy, aluminum-strontium alloy, ferrotungsten alloy, copper-iron alloy, aluminum ingot, terbium-dysprosium-iron alloy, dysprosium-iron alloy, cobalt powder and scrap steel are weighed, mixed and smelted to obtain molten steel; S2, refining the molten steel, adding a reinforcing phase, continuously casting, heating, and rolling to obtain a steel billet for chain accessories; Among them, the reinforcement phase is MoC, and the mass ratio of matrix and reinforcement phase is 110:6; S3. Heat the chain accessory steel billet to 1150°C at a heating rate of 40°C / min, keep it warm for 0.5h, and then cool it to room temperature; heat it to 800°C at a heating rate of 40°C / min, keep it warm for 1h, and then cool it to room temperature; heat it to 480°C at a heating rate of 60°C / min, keep it warm for 2h, and then cool it to room temperature to obtain chain accessory steel.

[0027] Example 4 The only difference between this embodiment and embodiment 2 is that, in this embodiment, the mass percentage of Sr added is 0.006%, the mass percentage of Dy added is 0.006%, and the mass percentage of Co added is 0.108%.

[0028] Example 5 The only difference between this embodiment and embodiment 2 is that, in this embodiment, the mass percentage of Sr added is 0.02%, the mass percentage of Dy added is 0.02%, and the mass percentage of Co added is 0.08%.

[0029] Example 6 The only difference between this embodiment and embodiment 2 is that, in this embodiment, the mass percentage of Sr added is 0.01%, the mass percentage of Dy added is 0.01%, and the mass percentage of Co added is 0.1%.

[0030] Example 7 The only difference between this embodiment and embodiment 6 is that in this embodiment, MoC is modified MoC, and its preparation method includes the following steps: 80 parts of MoC and 2.5 parts of vanadium powder are dry-mixed at a rotation speed of 150 rpm for 12 hours, press-formed, sintered at 1550° C. for 3.5 hours, and crushed to obtain modified MoC.

[0031] Example 8 The only difference between this embodiment and embodiment 6 is that in this embodiment, MoC is modified MoC, and its preparation method includes the following steps: 80 parts of MoC and 2.5 parts of boron powder are dry-mixed at a rotation speed of 150 rpm for 12 hours, press-formed, sintered at 1550°C for 3.5 hours, and crushed to obtain modified MoC.

[0032] Example 9 The only difference between this embodiment and embodiment 8 is that in this embodiment, MoC is modified MoC, and its preparation method includes the following steps: 80 parts of MoC, 2 parts of vanadium powder and 0.5 parts of boron powder are dry mixed at a rotation speed of 150 rpm for 12 hours, press-formed, sintered at 1550°C for 3.5 hours, and crushed to obtain modified MoC.

[0033] Example 10 The only difference between this embodiment and embodiment 9 is that in this embodiment, 80 parts of MoC, 2 parts of vanadium powder and 4.5 parts of boron powder are added.

[0034] Embodiment 11 The only difference between this embodiment and embodiment 9 is that in this embodiment, 80 parts of MoC, 2 parts of vanadium powder and 1 part of boron powder are added.

[0035] Example 12 The only difference between this embodiment and embodiment 9 is that in this embodiment, 80 parts of MoC, 2 parts of vanadium powder and 4 parts of boron powder are added.

[0036] Example 13 The only difference between this embodiment and embodiment 12 is that, in this embodiment, the heating rate of the first stage heat treatment is 30°C / min, the heating rate of the second stage heat treatment is 10°C / min, and the heating rate of the third stage heat treatment is 25°C / min.

[0037] Embodiment 14 The only difference between this embodiment and embodiment 12 is that, in this embodiment, the heating rate of the first stage heat treatment is 10°C / min, the heating rate of the second stage heat treatment is 30°C / min, and the heating rate of the third stage heat treatment is 25°C / min.

[0038] Embodiment 15 The only difference between this embodiment and embodiment 12 is that, in this embodiment, the heating rates of the first and second heat treatments are both 30°C / min, and the heating rate of the third heat treatment is 25°C / min.

[0039] Comparative Example 1 The difference between this comparative example and Example 1 is that in this comparative example, Dy is not added, the mass percentage of Sr added is 0.01%, and the mass percentage of Co added is 0.015%.

[0040] Comparative Example 2 The difference between this comparative example and Example 1 is that in this comparative example, Sr is not added, the mass percentage of Dy added is 0.01%, and the mass percentage of Co added is 0.015%.

[0041] Comparative Example 3 The difference between this comparative example and Example 1 is that in this comparative example, Co is not added, the mass percentage of Dy added is 0.0125%, and the mass percentage of Sr added is 0.0125%.

[0042] Comparative Example 4 The difference between this comparative example and Example 1 is that in this comparative example, Dy and Sr are not added, and the mass percentage of Co added is 0.025%.

[0043] Comparative Example 5 The only difference between this comparative example and Example 1 is that in this comparative example, Dy, Sr and Co are not added.

[0044] The chain accessory steels prepared in Examples 1 to 15 and Comparative Examples 1 to 5 were subjected to the following performance tests: ① Impact resistance test: According to the test method in GB / T 229-2020 "Charpy Pendulum Impact Test Method for Metallic Materials", the chain accessory steel sample blank is subjected to an impact energy test. The sample is a V-notch sample, the test temperature is 23°C, and the result is rounded to one decimal place.

[0045] ② Wear resistance test: The chain accessory steel is made into 10mm×10mm×30mm steel samples, and the wear tester (model: MLD-10) is used to test the wear of the samples. During the test, the lower sample is 40Cr, the rotation speed is 200r / min, the impact energy is 2J, the test time is 300min, and each cycle is 30min.

[0046] Measure the amount of wear and keep the result to three decimal places.

[0047] The test results are shown in Table 1 below: Table 1 Performance test results of Examples 1 to 15 and Comparative Examples 1 to 5

[0048] Compared with Comparative Examples 1 to 5, the impact energy of Example 1 is significantly increased and the wear amount is significantly reduced, indicating that when Sr, Dy and Co are added to the matrix of the chain accessory steel, the combined use of the three can improve the organizational structure of the chain accessory steel, refine the crystals, thereby forming a chain accessory steel with a stable and uniform internal structure, and significantly improving the wear resistance and impact resistance of the chain accessory steel.

[0049] Compared with Examples 2 and 4, the impact energy of Examples 5 to 6 is increased and the wear amount is reduced, indicating that when the mass ratio of the sum of the mass percentages of Sr and Dy to Co is 1:2 to 5, the wear resistance and impact resistance of the chain accessory steel can be further improved by adjusting the addition amounts of the three.

[0050] Compared with Examples 6 to 8, the impact energy of Example 9 is increased and the wear amount is reduced, indicating that the wear resistance and impact resistance of the chain accessory steel can be further improved by simultaneously modifying MoC with vanadium powder and boron powder.

[0051] Compared with Examples 9 to 10, the impact energy of Examples 11 to 12 is increased and the wear amount is reduced, indicating that when the mass ratio of MoC, vanadium powder and boron powder is 80:2:1 to 4, the wear resistance and impact resistance of the chain accessory steel can be further improved.

[0052] Compared with Examples 12 to 14, the impact energy of Example 15 is increased and the wear amount is reduced, indicating that when the heating rates of the first heat treatment and the third heat treatment are both greater than the heating rate of the third heat treatment, the wear resistance and impact resistance of the chain accessory steel can be further improved.

[0053] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly wear-resistant and impact-resistant chain accessory steel, comprising a matrix and a reinforcement phase, characterized in that: The matrix is ​​composed of the following components in percentage by mass: C 0.19%~0.24%, Mn 0.85%~1.25%, V 0.03%~0.1%, Nb 0.03%~0.05%, Sr 0.005%~0.035%, W 0.04%~0.085%, Cu 0.05%~0.09%, Al 0.09%~0.15%, Dy 0.005%~0.025%, B 0.002%~0.009%, Co 0.015%~0.33%, Tb 0.0018%~0.0092%, P≤0.012%, S≤0.009%, and the rest are iron and its inevitable impurities; the reinforcing phase is MoC; The mass ratio of the matrix to the reinforcement phase is 110:3-6.

2. The highly wear-resistant and impact-resistant chain accessory steel according to claim 1, characterized in that: The mass ratio of the sum of the mass percentages of the Sr and Dy to the mass ratio of the Co is 1:2-5.

3. The highly wear-resistant and impact-resistant chain accessory steel according to claim 1, characterized in that: The MoC is modified MoC, and the raw materials of the modified MoC include MoC, vanadium powder and boron powder.

4. The highly wear-resistant and impact-resistant chain accessory steel according to claim 3, characterized in that: The mass ratio of the MoC, vanadium powder and boron powder is 80:2:1-4.

5. The highly wear-resistant and impact-resistant chain accessory steel according to claim 3, characterized in that: The preparation method of the modified MoC comprises the following steps: dry mixing the MoC, the vanadium powder and the boron powder, press-forming, sintering and crushing to obtain the modified MoC.

6. The method for preparing a highly wear-resistant and impact-resistant chain accessory steel according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Weighing the components according to the mass percentage of the matrix, blending, smelting, and obtaining molten steel; S2, refining the molten steel, adding a reinforcing phase, continuously casting, heating, and rolling to obtain a steel billet for chain accessories; S3. heat treating the chain accessory steel billet to obtain the chain accessory steel.

7. The method for preparing a highly wear-resistant and impact-resistant chain accessory steel according to claim 6, characterized in that: In step S2, the median particle size of the reinforcing phase is 20-50 μm.

8. The method for preparing a highly wear-resistant and impact-resistant chain accessory steel according to claim 6, characterized in that: In step S3, the heat treatment is divided into a first stage heat treatment, a second stage heat treatment and a third stage heat treatment. In the first stage heat treatment, the temperature is raised to 1050-1150°C, the heat preservation time is 0.5-1.5 hours, and the temperature is cooled to room temperature; in the second stage heat treatment, the temperature is raised to 650-800°C, the heat preservation time is 1-2 hours, and the temperature is cooled to room temperature; in the third stage heat treatment, the temperature is raised to 400-480°C, the temperature is kept for 2-3 hours, and the temperature is cooled to room temperature.

9. The method for preparing a highly wear-resistant and impact-resistant chain accessory steel according to claim 8, characterized in that: During the first stage heat treatment and the second stage heat treatment, the heating rate is independently 10-40°C / min; during the third stage heat treatment, the heating rate is 25-60°C / min.

10. The method for preparing a highly wear-resistant and impact-resistant chain accessory steel according to claim 9, characterized in that: The heating rates of the first heat treatment and the second heat treatment are independently greater than the heating rate of the third heat treatment.

Images