High wear resistance high silicon high chromium cast iron and preparation method thereof

Abstract

The application provides a high wear-resisting high-silicon high-chromium cast iron and a preparation method thereof, and belongs to the technical field of wear-resisting materials.The high wear-resisting high-silicon high-chromium cast iron provided by the application contains the following components in terms of mass content: C 2.0-3.2%, Si 2.00-2.5%, Cr 12.0-13.0%, Mn 0-2%, Ni 0-2.5%, Mo 0-3%, P 0-0.06%, S 0-0.06%, and the balance of Fe.The application increases the addition amount of Si in the alloying element to 2.00-2.50 wt%, promotes the segregation of elements such as C and Cr in the liquid phase during solidification, and further increases the content of eutectic carbide in the structure; the hardness and wear resistance are improved, the fluidity is good during casting, and the filling capacity is improved.The results of the examples show that the surface hardness of the high wear-resisting high-silicon high-chromium cast iron provided by the application can be up to HRC 65.

Description

Technical Field

[0001] This invention relates to the field of wear-resistant materials technology, and in particular to a high-wear-resistant high-silicon high-chromium cast iron and its preparation method. Background Technology

[0002] Chromium-based high-chromium cast iron is one of the most widely used wear-resistant materials in my country. It possesses excellent wear resistance and its production process is not complex. It is recognized as a high-performance wear-resistant material and is widely used in mining, cement, metallurgy, and power industries. In chromium-based high-chromium cast iron, the large addition of chromium transforms the M3C type carbides in white cast iron into M7C3 type carbides. M7C3 type carbides have high hardness, thus giving high-chromium cast iron excellent wear resistance; the higher the chromium content, the better the wear resistance.

[0003] Therefore, how to improve the surface hardness and wear resistance of high-chromium cast iron without increasing the chromium content has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to provide a high-wear-resistant, high-silicon, high-chromium cast iron. The high-chromium cast iron provided by this invention can achieve higher surface hardness and thus better wear resistance without increasing the chromium content.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a high-wear-resistant, high-silicon, high-chromium cast iron, which, by mass content, contains the following components: C 2.0~3.2%, Si 2.00~2.5%, Cr 12.0~13.0%, Mn 0~2%, Ni 0~2.5%, Mo 0~3%, P 0~0.06%, S 0~0.06%, and the balance Fe.

[0007] Preferably, the high wear-resistant high-silicon high-chromium cast iron, by mass content, comprises the following components: C 2.2~3.1%, Si 2.05~2.45%, Cr 12.1~12.8%, Mn 0.1~1.5%, Ni 0.05~2.0%, Mo 0.01~2%, P 0~0.05%, S 0~0.05%, and the balance Fe.

[0008] Preferably, the high wear-resistant high-silicon high-chromium cast iron comprises, by mass content, the following components: C 2.4~3.0%, Si 2.1~2.4%, Cr 12.11~12.6%, Mn 0.2~1.2%, Ni 0.08~1.8%, Mo 0.02~1.0%, P 0~0.04%, S 0~0.04%, and the balance Fe.

[0009] Preferably, the high wear-resistant high-silicon high-chromium cast iron, by mass content, comprises the following components: C 2.6~2.9%, Si 2.15~2.35%, Cr 12.12~12.5%, Mn 0.3~0.9%, Ni 0.11~1.6%, Mo 0.03~0.5%, P 0~0.03%, S 0~0.02%, and the balance Fe.

[0010] This invention provides a method for preparing high-wear-resistant, high-silicon, high-chromium cast iron as described in the above technical solution, comprising the following steps:

[0011] (1) The alloy raw materials are melted and then cast to obtain high silicon and high chromium cast iron castings;

[0012] (2) The high silicon and high chromium cast iron castings obtained in step (1) are heat-treated to obtain high silicon and high chromium cast iron with high wear resistance.

[0013] Preferably, the heat treatment in step (2) is one of the following four methods:

[0014] Method 1: Oil bath quenching followed by low-temperature tempering;

[0015] Method 2: Salt bath quenching followed by low-temperature tempering;

[0016] Method 3: Salt bath isothermal treatment;

[0017] Method 4: Subcritical treatment.

[0018] Preferably, in Method 1, the oil bath quenching temperature is 860~980℃, the oil bath quenching holding time is 4~8 hours, and the oil bath temperature is 50~120℃; the low-temperature tempering temperature is 230~320℃.

[0019] Preferably, in Method 2, the salt bath quenching temperature is 860~980℃, the salt bath quenching holding time is 4~8 hours, the salt bath quenching temperature is 230~320℃, and the low temperature tempering temperature is 230~300℃.

[0020] Preferably, in method three, the first holding temperature of the salt bath isothermal treatment is 860~980℃, the first holding time of the salt bath isothermal treatment is 4~8 hours, the isothermal temperature of the salt bath isothermal treatment is 230~320℃, and the isothermal time of the salt bath isothermal treatment is 4~10 hours.

[0021] Preferably, in method four, the subcritical treatment temperature is 400~550℃, the subcritical treatment time is 4~8 hours, and the cooling method for the subcritical treatment is air cooling to room temperature.

[0022] This invention provides a high-wear-resistant, high-silicon, high-chromium cast iron, comprising the following components by mass: C 2.0~3.2%, Si 2.00~2.5%, Cr 12.0~13.0%, Mn 0~2%, Ni 0~2.5%, Mo 0~3%, P 0~0.06%, S 0~0.06%, and the balance Fe. The high-chromium cast iron provided by this invention, with a Cr content of 12.0~13.0%, increases the Si content in the alloying elements to 2.00~2.50wt%, shifting the eutectic point to the left and increasing the content of eutectic carbides. This forms a silicon-rich, chromium-poor proeutectic phase, increasing the carbon and chromium content in the eutectic structure, which is beneficial for forming M7C3 type carbides with higher hardness and better wear resistance. This improves the hardness and wear resistance of the high-chromium cast iron while maintaining a relatively low Cr content. The results of the embodiments show that the surface hardness of the high-wear-resistant, high-silicon, high-chromium cast iron obtained by this invention can reach HRC65. Detailed Implementation

[0023] This invention provides a high-wear-resistant, high-silicon, high-chromium cast iron, which, by mass content, contains the following components: C 2.0~3.2%, Si 2.00~2.5%, Cr 12.0~13.0%, Mn 0~2%, Ni 0~2.5%, Mo 0~3%, P 0~0.06%, S 0~0.06%, and the balance Fe.

[0024] In this invention, the high wear-resistant high silicon high chromium cast iron, by mass content, comprises 2.0-3.2% C, preferably 2.2-3.1%, further preferably 2.4-3.0%, and most preferably 2.6-2.9%. In this invention, carbon affects the mechanical properties of the casting. Carbon exists in high-chromium cast iron in two forms: some carbon is dissolved in the metal matrix, which improves the hardenability of the matrix and makes it easier for the high-chromium cast iron matrix to obtain martensite. Martensite is a supersaturated solid solution formed by carbon dissolving in ferrite. A large number of dissolved carbon atoms cause severe lattice distortion in the matrix, which increases the hardness of the matrix and thus strengthens the matrix and provides a solid support for carbides. The other part of carbon combines with alloying elements to form carbides. Carbides have high hardness, and their distribution in the matrix can significantly improve the hardness and wear resistance of high-chromium cast iron. As the carbon content increases, the number of carbides in high-chromium cast iron increases, thereby increasing the hardness and wear resistance of the cast iron. However, when the carbon content is too high, the number of carbides is large and coarse. They contact and connect with each other in the matrix. These carbides will cut the matrix of the cast iron, increase the brittleness of high-chromium cast iron, reduce its impact toughness, and thus weaken the comprehensive mechanical properties of high-chromium cast iron. The present invention limits the amount of C within the above-mentioned range, which is beneficial for preparing high-chromium cast iron with good comprehensive mechanical properties.

[0025] In this invention, the high-wear-resistant high-silicon high-chromium cast iron, by mass content, comprises 2.00~2.5% Si, more preferably 2.05~2.45%, further preferably 2.1~2.4%, and most preferably 2.15~2.35% Si. In this invention, the Si can form silicon-rich and chromium-poor proeutectic austenite during the solidification of high-chromium cast iron, promoting the segregation of carbon, chromium, and other elements into the liquid phase, increasing the carbon and chromium content in the liquid phase, and facilitating the formation of M7C3 type carbides with higher hardness and better wear resistance; it shifts the eutectic point to the left, increasing the content of eutectic carbides; the presence of silicon reduces the eutectic reaction temperature range of high-chromium cast iron, making the morphology of carbides in the eutectic structure finer and more dispersed; it increases the liquid phase during eutectic transformation, resulting in better fluidity during casting and improving the material's casting filling ability; silicon reduces the hardenability of the matrix, promotes pearlite formation, and significantly reduces the hardness and wear resistance of the alloy, therefore, it is necessary to reasonably control the silicon content in high-chromium cast iron. The present invention limits the amount of Si to the above range, which is beneficial to prepare high-chromium cast iron with higher surface hardness and thus high wear resistance without increasing the chromium content.

[0026] In this invention, the high-wear-resistant high-silicon high-chromium cast iron, by mass content, comprises 12.0-13.0% Cr, more preferably 12.1-12.8%, further preferably 12.11-12.6%, and most preferably 12.12-12.5%. In this invention, Cr is one of the main elements determining carbide type and is a fundamental element of high-chromium cast iron. Chromium exists in high-chromium cast iron in two forms: one part promotes carbide formation, altering the structure, properties, and morphology of the carbides; because chromium is a strong carbide-forming element, during the solidification process of high-chromium cast iron, some chromium combines with carbon, which is beneficial for the transformation of M3C-type carbides in white cast iron into M7C3-type carbides. M7C3-type carbides have very high hardness, thus giving high-chromium cast iron good wear resistance; the other part is dissolved in the matrix of high-chromium cast iron. Since chromium is one of the main elements improving hardenability, it can improve the stability of austenite, shifting its continuous cooling curve to the right, thereby greatly improving hardenability. The present invention limits the amount of Cr to the above range, which is beneficial for preparing high-chromium cast iron with high wear resistance.

[0027] In this invention, the mass ratio of Cr to C in the high-wear-resistant high-silicon high-chromium cast iron is preferably >4. Controlling the Cr / C ratio within the above range is beneficial for preparing high-silicon high-chromium cast iron.

[0028] In this invention, the high-wear-resistant high-silicon high-chromium cast iron comprises, by mass content, 0-2% Mn, more preferably 0.1-1.5%, further preferably 0.2-1.2%, and most preferably 0.3-0.9%. In this invention, Mn has a strong effect on improving hardenability and also stabilizes austenite. A portion of the manganese in the high-chromium cast iron dissolves in the austenite, expanding the austenite phase region, lowering the Ms point, shifting the continuous cooling curve to the right, increasing the amount of residual austenite, and reducing the martensite content, thereby reducing the hardness and wear resistance of the high-chromium cast iron. However, excessive manganese dissolves in carbides, reducing the hardness of the carbides and making them more brittle, making them prone to cracking and breakage during wear. This invention limits the amount of Mn within the above range, which is beneficial for preparing high-chromium cast iron with good mechanical properties and high wear resistance.

[0029] In this invention, the high-wear-resistant, high-silicon, high-chromium cast iron comprises, by mass content, 0-2.5% Ni, more preferably 0.05-2.0%, further preferably 0.08-1.8%, and most preferably 0.11-1.6%. In this invention, Ni improves the hardenability of cast iron, densifies the matrix, strengthens the matrix structure, and expands the austenite phase region by being a non-carbide-forming element, thus shifting the continuous cooling curve to the right and reducing the critical cooling rate, thereby lowering the martensite initiation temperature and improving hardenability. Nickel also inhibits pearlite formation; this inhibition is more pronounced when added simultaneously with molybdenum. However, nickel is expensive, and excessive addition increases the cost of high-chromium cast iron. This invention limits the amount of Ni within the above range, which is beneficial for improving the hardenability of high-chromium cast iron while controlling costs.

[0030] In this invention, the high-wear-resistant high-silicon high-chromium cast iron comprises, by mass content, 0-3% Mo, more preferably 0.01-2%, further preferably 0.02-1.0%, and most preferably 0.03-0.5% Mo. In this invention, Mo is an element that strongly enhances hardenability. In high-chromium cast iron, a portion of the molybdenum is dissolved in the austenitic matrix, and a portion forms Mo2C carbides with carbon. The dissolved molybdenum significantly improves the hardenability of high-chromium cast iron, strongly delaying the transformation time from austenite to pearlite, shifting the continuous cooling curve of high-chromium cast iron to the right, and reducing the critical cooling rate. However, molybdenum is expensive, and excessive addition increases the cost of high-chromium cast iron. This invention limits the amount of Mo within the above range, which is beneficial for preparing high-wear-resistant high-chromium cast iron while controlling costs.

[0031] In this invention, the high-wear-resistant, high-silicon, high-chromium cast iron comprises, by mass content, 0-0.06% P, more preferably 0-0.05% P, further preferably 0-0.04% P, and most preferably 0-0.03%. In this invention, P is an impurity introduced during the production process that can affect the mechanical properties of the casting, particularly reducing toughness and density, leading to cracking. This invention limits the amount of P within the above range, which is beneficial for preventing cracking in the prepared casting.

[0032] In this invention, the high-wear-resistant high-silicon high-chromium cast iron, by mass content, comprises 0-0.06% S, more preferably 0-0.05%, further preferably 0-0.04%, and most preferably 0-0.02% S. In this invention, S is an impurity introduced during the production process. Limiting the amount of S within the above range in this invention is beneficial for preparing high-chromium cast iron with stable mechanical properties.

[0033] In this invention, the high wear-resistant high-silicon high-chromium cast iron comprises the balance Fe by mass content.

[0034] By using the above-mentioned raw materials and limiting their dosage within the above-mentioned range, the present invention enables the prepared high-chromium cast iron to have good casting and forming ability, high surface hardness, and wear resistance.

[0035] This invention also provides a method for preparing the above-mentioned high-wear-resistant high-silicon high-chromium cast iron, comprising the following steps:

[0036] (1) The alloy raw materials are melted and then cast to obtain high silicon and high chromium cast iron castings;

[0037] (2) The high silicon and high chromium cast iron castings obtained in step (1) are heat-treated to obtain high silicon and high chromium cast iron with high wear resistance.

[0038] This invention involves melting and casting alloy raw materials to obtain high-silicon, high-chromium cast iron castings.

[0039] This invention does not have any special restrictions on the source of alloy raw materials, as long as the proportions meet the content requirements of each element in this application.

[0040] This invention does not impose any special limitations on the specific smelting operations; conventional smelting methods in the field can be used.

[0041] This invention does not impose any special limitations on the specific casting operation; conventional casting methods in the field can be used.

[0042] This invention does not impose any special limitations on the structure of the high-silicon, high-chromium cast iron castings; they can be made into shapes commonly found in the art. Because the addition of Si increases the eutectic content, this invention exhibits excellent casting properties, making it suitable for casting complex wear-resistant parts. Additionally, it is also suitable for casting simple grinding balls, grinding segments, etc.

[0043] In a specific embodiment of the present invention, the high-silicon, high-chromium cast iron casting is a grinding ball. In the present invention, the diameter of the grinding ball is preferably 10-60 mm, more preferably 10-50 mm, and most preferably 10-40 mm.

[0044] After obtaining the high-silicon high-chromium cast iron casting, the present invention performs heat treatment on the high-silicon high-chromium cast iron casting to obtain high-wear-resistant high-silicon high-chromium cast iron.

[0045] In this invention, the heat treatment is preferably one of the following four methods:

[0046] Method 1: Oil bath quenching followed by low-temperature tempering;

[0047] Method 2: Salt bath quenching followed by low-temperature tempering;

[0048] Method 3: Salt bath isothermal treatment;

[0049] Method 4: Subcritical treatment. This invention employs the above method to heat treat high-silicon, high-chromium cast iron castings, which helps eliminate cast iron stress, improve the matrix structure, and increase hardness and wear resistance.

[0050] In this invention, the preferred specific operation of method one is as follows: heating and holding the casting in a heat treatment furnace, then quenching it in an oil bath, and finally tempering it at a low temperature in the heat treatment furnace. By controlling the specific heat treatment operations as described above, this invention helps to improve the wear resistance and performance of the casting.

[0051] In this invention, the oil bath quenching temperature in Method 1 is preferably 860~980℃, more preferably 880~960℃, and even more preferably 900~940℃; the holding time for oil bath quenching is preferably 4~8 hours, more preferably 4~6 hours, and even more preferably 4~5 hours; the oil bath temperature for oil bath quenching is preferably 50~120℃, more preferably 60~110℃, and even more preferably 70~100℃. By controlling the oil bath quenching parameters within the above ranges, this invention helps to improve the hardness and wear resistance of high-chromium cast iron.

[0052] In this invention, the oil bath quenching time is preferably 10-30 min, more preferably 15-25 min, and even more preferably 18-23 min. By controlling the oil bath time within the above range, this invention enables the prepared high-chromium wear-resistant cast iron to have uniform hardness and minimal deformation.

[0053] In this invention, the temperature of the low-temperature tempering is preferably 230~320℃, more preferably 230~300℃, and even more preferably 230~280℃. By controlling the parameters of low-temperature tempering after oil bath quenching within the above range, this invention helps to eliminate or reduce internal stress, reduce brittleness, improve toughness, improve mechanical properties, and thus improve the performance of high-chromium cast iron.

[0054] In this invention, the preferred specific operation of method two is as follows: the casting is heated and held at a temperature in a heat treatment furnace, then quenched in a salt bath, and then tempered at a low temperature in a heat treatment furnace. By controlling the specific heat treatment operations as described above, this invention helps to improve the wear resistance and performance of the casting.

[0055] In this invention, the preferred temperature for salt bath quenching in method two is 860-980℃, more preferably 880-960℃, and even more preferably 900-940℃; the preferred holding time for salt bath quenching is 4-8 hours, more preferably 4-6 hours, and even more preferably 4-5 hours; the preferred salt bath temperature for salt bath quenching is 230-320℃, more preferably 250-300℃, and even more preferably 260-290℃. By controlling the parameters of salt bath quenching within the above ranges, this invention helps to improve the hardness and wear resistance of high-chromium cast iron.

[0056] In this invention, the salt bath time during salt bath quenching is preferably 10-30 min, more preferably 15-25 min, and even more preferably 18-23 min. By controlling the salt bath time within the above range, this invention enables the prepared high-chromium wear-resistant cast iron to have uniform hardness and minimal deformation.

[0057] In this invention, the temperature of the low-temperature tempering is preferably 230~300℃, more preferably 230~280℃, and even more preferably 230~250℃. By controlling the parameters of the low-temperature tempering after salt bath quenching within the above range, this invention helps to eliminate or reduce internal stress, reduce brittleness, improve toughness, improve mechanical properties, and thus improve the performance of high-chromium cast iron.

[0058] In this invention, the preferred specific operation of method three is as follows: heating the casting to a first holding temperature and holding it thereafter, then placing it in a salt bath for isothermal treatment. By controlling the specific heat treatment operations as described above, this invention facilitates the preparation of high-chromium cast iron with high hardness, good toughness, and resistance to deformation and cracking.

[0059] In this invention, the first holding temperature of the salt bath isothermal treatment in method three is preferably 860~980℃, more preferably 880~960℃, and even more preferably 900~940℃; the first holding time of the salt bath isothermal treatment is preferably 4~8 hours, more preferably 4~6 hours, and even more preferably 4~5 hours; the isothermal temperature of the salt bath isothermal treatment for salt bath quenching is preferably 230~320℃, more preferably 250~300℃, and even more preferably 260~290℃; the salt bath isothermal treatment time is preferably 4~10 hours, more preferably 4~8 hours, and even more preferably 4~6 hours. By controlling the parameters of the salt bath isothermal treatment within the above ranges, this invention helps to improve the hardness and toughness of high-chromium cast iron and also prevents deformation and cracking of the prepared high-chromium cast iron.

[0060] In this invention, the preferred specific operation of method four is to heat the casting to a subcritical treatment temperature, hold it at that temperature, and then air-cool it to room temperature. By controlling the specific heat treatment operation as described above, this invention helps to improve the hardness and wear resistance of high-chromium cast iron.

[0061] In this invention, the subcritical treatment temperature in method four is preferably 860~980℃, more preferably 880~960℃, and even more preferably 900~940℃; the subcritical treatment time is preferably 4~8 hours, more preferably 4~7 hours, and even more preferably 4~6 hours; the cooling method for the subcritical treatment is preferably air cooling to room temperature. By controlling the parameters of the salt bath isothermal treatment within the above ranges, this invention is beneficial for improving the hardness and wear resistance of high-chromium cast iron.

[0062] This invention, by controlling the heat treatment conditions of high-silicon, high-chromium cast iron castings, can produce high-chromium cast iron with higher hardness and wear resistance, and can also improve the machinability and performance of high-chromium cast iron.

[0063] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0064] Example 1

[0065] Based on mass content, the high wear-resistant high silicon high chromium cast iron in this embodiment has the following composition: C 2.64%, Si 2.14%, Cr 12.12%, Mn 0.49%, Ni 0.12%, Mo 0.03%, P 0.023%, S 0.016%, and the balance Fe.

[0066] The preparation method of high wear-resistant high-silicon high-chromium cast iron in this embodiment is as follows:

[0067] (1) Place the alloy raw material in a melting furnace and heat it to 1600°C to completely melt the furnace charge and cast it into a high silicon high chromium cast iron casting. The high silicon high chromium cast iron casting is a grinding ball with a diameter of 40 mm. At this time, the surface hardness of the grinding ball is HRC: 54.5.

[0068] (2) The high silicon and high chromium cast iron casting obtained in step (1) is placed in a heat treatment furnace and heated to 930°C, held for 4 hours, and then placed in a 230°C salt bath for isothermal treatment for 6 hours to obtain high wear-resistant high silicon and high chromium cast iron; the surface hardness of the high wear-resistant high silicon and high chromium cast iron after heat treatment is HRC: 62.

[0069] Example 2

[0070] Based on mass content, the high wear-resistant high silicon high chromium cast iron in this embodiment has the following composition: C 2.68%, Si 2.22%, Cr 12.23%, Mn 0.5%, Ni 0.14%, Mo 0.03%, P 0.028%, S 0.016%, and the balance Fe.

[0071] The preparation method of high wear-resistant high-silicon high-chromium cast iron in this embodiment is as follows:

[0072] (1) Place the alloy raw material in a melting furnace and heat it to 1600°C to completely melt the furnace charge and cast it into a high silicon high chromium cast iron casting. The high silicon high chromium cast iron casting is a grinding ball with a diameter of 60 mm. At this time, the surface hardness of the grinding ball is HRC: 55.

[0073] (2) The high silicon and high chromium cast iron casting obtained in step (1) is placed in a heat treatment furnace and heated to 930°C. It is kept at that temperature for 4 hours, then placed in an 80°C oil bath for 10 minutes to quench. It is then taken out and placed in a heat treatment furnace for tempering at 230°C for 3 hours to obtain high wear-resistant high silicon and high chromium cast iron. The surface hardness of the high wear-resistant high silicon and high chromium cast iron after heat treatment is HRC: 63.5.

[0074] Example 3

[0075] Based on mass content, the high wear-resistant high silicon high chromium cast iron in this embodiment has the following composition: C 2.7%, Si 2.12%, Cr 12.43%, Mn 0.5%, Ni 0.14%, Mo 0.03%, P 0.028%, S 0.016%, and the balance Fe.

[0076] The preparation method of high wear-resistant high-silicon high-chromium cast iron in this embodiment is as follows:

[0077] (1) Place the alloy raw material in a melting furnace and heat it to 1600°C to completely melt the furnace charge and cast it into a high silicon high chromium cast iron casting. The high silicon high chromium cast iron casting is a grinding ball with a diameter of 40 mm. At this time, the surface hardness of the grinding ball is HRC: 55.5.

[0078] (2) The high silicon and high chromium cast iron obtained in step (1) is placed in a heat treatment furnace and heated to 930°C, held for 4 hours, and then placed in a 230°C salt bath for isothermal treatment for 6 hours to obtain high wear-resistant high silicon and high chromium cast iron; the surface hardness of the high wear-resistant high silicon and high chromium cast iron after heat treatment is HRC: 65.

[0079] Comparative Example

[0080] Table 1 lists the composition (mass molecular weight) % and hardness of high-chromium cast iron 15-3 as specified by Climax Molybdenum Company of the United States, and the composition (mass molecular weight) % and hardness of the present invention, as a comparison between the prior art and the present invention.

[0081] Table 1 Comparison of composition and hardness between existing technology and the present invention.

[0082]

[0083] As can be seen from the above embodiments and comparative examples, the high-silicon, high-chromium wear-resistant cast iron prepared by the method provided by the present invention has high surface hardness. The present invention improves the hardness and wear resistance of high-silicon, high-chromium cast iron by increasing the amount of Si in the alloying element to 2.00~2.50%, while maintaining a relatively low Cr content.

[0084] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing high-wear-resistant, high-silicon, high-chromium cast iron, characterized in that, Based on mass content, high wear-resistant high silicon high chromium cast iron has the following composition: C 2.7%, Si 2.12%, Cr 12.43%, Mn 0.5%, Ni 0.14%, Mo 0.03%, P 0.028%, S 0.016%, and the balance Fe; The preparation method is as follows: (1) Place the alloy raw material in a melting furnace and heat it to 1600°C to completely melt the furnace charge and cast it into a high silicon high chromium cast iron casting. The high silicon high chromium cast iron casting is a grinding ball with a diameter of 40 mm. At this time, the surface hardness of the grinding ball is HRC: 55.

5. (2) The high silicon and high chromium cast iron obtained in step (1) is placed in a heat treatment furnace and heated to 930°C, held for 4 hours, and then placed in a 230°C salt bath for isothermal treatment for 6 hours to obtain high wear-resistant high silicon and high chromium cast iron; the surface hardness of the high wear-resistant high silicon and high chromium cast iron after heat treatment is HRC: 65.

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