High-hardness chromium alloy wear-resistant steel ball and preparation process thereof

Abstract

The invention discloses a high-hardness chromium alloy wear-resistant steel ball which comprises a wear-resistant steel ball body, and the wear-resistant steel ball body comprises the following elements in percentage by weight: 1.5-3.5 wt% of carbon and 0.8-1.6 wt% of silicon oxide. The invention discloses a preparation process of a high-hardness chromium alloy wear-resistant steel ball. The preparation process comprises the following steps that S1, waste steel, ferromolybdenum and low-carbon ferromanganese are put into a hot melting furnace according to a certain weight ratio to be molten; according to the wear-resistant steel ball, the spherical mold core is placed in the spherical casting mold and is subjected to fractional casting, the high-chromium wear-resistant base layer and the high-chromium wear-resistant outer layer are formed after the spherical casting mold rotates at a high speed, the wear-resistant effect of the wear-resistant steel ball body is improved in cooperation with the wear-resistant coating, and the service life is prolonged; the eccentric protrusions are formed in the hollow cavity of the wear-resistant steel ball body, so that the cast steel ball can move in different tracks when rotating in a ball mill, materials in a certain area are prevented from being ground in a concentrated mode, uniform grinding of the materials is achieved, and the grinding effect is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wear-resistant steel balls, and particularly to a high-hardness chromium alloy wear-resistant steel ball and a preparation process thereof. Background Art

[0002] Wear-resistant steel balls are grinding media used for crushing materials in ball mills. Common wear-resistant steel balls can be divided into forged steel balls, cast steel balls and hot-rolled steel balls according to different forging methods. They are made by cutting round steel and forging with an air hammer. The wear resistance of forged steel balls is greatly related to the material of the round steel used, as well as impurities or the quality of the round steel.

[0003] The advantages of forged steel balls are small breakage rate, good wear resistance, low price and high cost performance. Chromium alloy in cast steel balls is the main component of cast steel balls. Their oxidation resistance and corrosion resistance to high sulfur, diesel fuel and seawater are poor, and their strength density ratio is lower than that of forged steel balls. The breakage rate is much higher than that of steel balls produced by other processes.

[0004] During the actual use of conventional cast steel balls for ball mills, the wear-resistant steel balls are severely worn when in long-term contact with materials, resulting in a low service life. Moreover, when the cast steel balls rotate in the ball mill, they often move along the same trajectory, which easily leads to grinding of materials concentrated in a certain area, affecting the grinding effect of the materials. Now, a high-hardness chromium alloy wear-resistant steel ball and a preparation process thereof are proposed to solve the above problems. Summary of the Invention

[0005] Aiming at the deficiencies and defects in the prior art, the present invention provides a high-hardness chromium alloy wear-resistant steel ball and a preparation process thereof, which are used to solve the technical problems that in the actual use of conventional cast steel balls for ball mills, the wear-resistant steel balls are severely worn when in long-term contact with materials, resulting in a low service life, and when the cast steel balls rotate in the ball mill, they often move along the same trajectory, which easily leads to grinding of materials concentrated in a certain area, affecting the grinding effect of the materials.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A high-hardness chromium alloy wear-resistant steel ball and a preparation process thereof, including a wear-resistant steel ball body. The wear-resistant steel ball body comprises elements in the following weight percentages: carbon content: 1.5 - 3.5 wt%, silicon oxide content: 0.8 - 1.6 wt%, manganese oxide content: 1.0 - 2.6 wt%, chromium content: 22.0 - 26.0 wt%, nickel oxide content: 0.08 - 0.16 wt%, cobalt oxide content: 0.15 - 0.25 wt%, molybdenum oxide content: 0.10 - 0.20 wt%, boron oxide content: 0.10 - 0.15 wt%, titanium oxide content: 0.12 - 0.20 wt%, and the balance is Fe and inevitable impurities, and also includes a small amount of rare earth oxides.

[0007] The wear-resistant steel ball body is composed of a high-chromium wear-resistant base layer, a high-chromium wear-resistant outer layer, and a wear-resistant coating. The high-chromium wear-resistant base layer is the innermost layer of the wear-resistant steel ball body, the high-chromium wear-resistant outer layer is the outermost layer of the wear-resistant steel ball body, and the wear-resistant coating is covered on the surface of the high-chromium wear-resistant outer layer.

[0008] Preferably, a hollow cavity is provided in the high-chromium wear-resistant base layer, an eccentric protrusion is provided on the annular inner wall of the hollow cavity, and the cross-section of the eccentric protrusion is arc-shaped.

[0009] Preferably, the high-chromium wear-resistant base layer, the high-chromium wear-resistant outer layer, and the eccentric protrusion are integrally cast and formed.

[0010] Preferably, the material of the wear-resistant coating is titanium nitride, and the wear-resistant coating is covered on the surface of the high-chromium wear-resistant outer layer by physical vapor deposition of materials.

[0011] A preparation process of a high-hardness chromium alloy wear-resistant steel ball includes the following processes: S1: Put waste steel, ferromolybdenum, and low-carbon ferromanganese into a melting furnace according to a certain weight ratio for melting. The melting temperature in the melting furnace is controlled at 1680 - 1760 °C. After the raw materials in the melting furnace are completely melted, then put ferrochrome, ferronickel, ferrosilicon, cobalt oxide, and titanium oxide, as well as borax and some rare earth oxides into it for melting, keep warm for 5.0 - 10.0 min, and stir the molten liquid after melting is completed, take samples and adjust the content of each element in the molten liquid to obtain a uniform basic casting liquid; S2: Make a spherical core, place the spherical core in a spherical casting mold, combine the casting molds loaded with the spherical core to form a closed casting space, pour the basic casting molten liquid into the casting mold in batches, the interval time between batches is set at 3.0 - 7.0 min, and the casting temperature is set at 1250 - 1650 °C; S3: During the batch casting process, make the casting mold rotate at a high speed, and use the centrifugal force to make the basic casting molten liquid evenly adhere to the inner wall of the mold to form a hollow spherical structure. After casting is completed, take out the spherical core in the casting mold to obtain a rough wear-resistant steel ball; S4: After taking out the rough wear-resistant steel ball from the casting mold, send it into a quenching furnace to heat it to 900 - 1100 °C and keep warm. After keeping warm, perform a first quenching, then heat the wear-resistant steel ball to 1050 - 1250 °C again and keep warm. After keeping warm, perform a second quenching. Finally, send the quenched wear-resistant steel ball into a tempering furnace for tempering treatment and keep warm, and naturally cool it in the air to obtain a finished wear-resistant steel ball; S5: Cover the surface of the finished wear-resistant steel ball with a wear-resistant coating made of titanium nitride by physical vapor deposition of materials.

[0012] Preferably, the material of the spherical core is silicon carbide ceramic or aluminum nitride ceramic. An arc-shaped groove is provided on the annular side wall of the spherical core, and the arc-shaped groove is exposed in the spherical casting mold.

[0013] Preferably, a process hole is provided on the spherical casting mold, and the spherical core can be taken out through the process hole after casting is completed.

[0014] Preferably, the high-speed rotation of the casting mold is carried out on a high-speed rotating machine.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. By placing the spherical core in the spherical casting mold and performing sub-casting, driving the spherical casting mold to rotate at high speed by a high-speed rotating machine to form a high-chromium wear-resistant base layer and a high-chromium wear-resistant outer layer, and covering the surface of the high-chromium wear-resistant outer layer with a wear-resistant coating made of titanium nitride material by means of material vapor deposition, the wear resistance of the wear-resistant steel ball body is improved and the service life is extended.

[0016] 2. By providing an arc-shaped groove on the spherical core and exposing the arc-shaped groove in the spherical casting mold, after the spherical casting mold is formed, an eccentric protrusion is formed in the hollow cavity of the wear-resistant steel ball body, so that the casting steel ball can move along different trajectories when rotating in the ball mill, preventing the concentrated grinding of the material in a certain area, realizing the uniform grinding of the material, and improving the grinding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a three-dimensional sectional structure schematic diagram of a high-hardness chromium alloy wear-resistant steel ball proposed by the present invention; Figure 2 is a partial sectional view schematic diagram of a high-hardness chromium alloy wear-resistant steel ball proposed by the present invention; Figure 3 is a sectional view schematic diagram of a high-hardness chromium alloy wear-resistant steel ball proposed by the present invention.

[0018] In the figure: 1 wear-resistant steel ball body, 2 high-chromium wear-resistant base layer, 3 high-chromium wear-resistant outer layer, 4 wear-resistant coating, 5 hollow cavity, 6 eccentric protrusion. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Embodiment

[0021] Refer to Figures 1-3 As shown, a high-hardness chromium alloy wear-resistant steel ball includes a wear-resistant steel ball body 1. The wear-resistant steel ball body 1 includes the following elements by weight percentage: carbon content: 1.5 wt%, silicon oxide content: 0.8 wt%, manganese oxide content: 1.0 wt%, chromium content: 22.0 wt%, nickel oxide content: 0.08 wt%, cobalt oxide content: 0.15 wt%, molybdenum oxide content: 0.10 wt%, boron oxide content: 0.10 wt%, titanium oxide content: 0.12 wt%, and the balance is Fe and inevitable impurities, and also includes a small amount of rare earth oxides.

[0022] The wear-resistant steel ball body 1 is composed of a high-chromium wear-resistant base layer 2, a high-chromium wear-resistant outer layer 3, and a wear-resistant coating 4. The high-chromium wear-resistant base layer 2 is the innermost layer of the wear-resistant steel ball body 1, the high-chromium wear-resistant outer layer 3 is the outermost layer of the wear-resistant steel ball body 1, and the wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3. The high-chromium wear-resistant base layer 2 and the high-chromium wear-resistant outer layer 3 cooperate with the wear-resistant coating material to form the wear-resistant coating 4 by physical vapor deposition, which improves the wear resistance of the wear-resistant steel ball body 1 and extends the service life. A hollow cavity 5 is provided in the high-chromium wear-resistant base layer 2, and an eccentric protrusion 6 is provided on the annular inner wall of the hollow cavity 5. The cross-section of the eccentric protrusion 6 is arc-shaped. The high-chromium wear-resistant base layer 2, the high-chromium wear-resistant outer layer 3, and the eccentric protrusion 6 are integrally cast. The material of the wear-resistant coating 4 is titanium nitride, and the wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3 by physical vapor deposition. An arc-shaped groove is provided on the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. After the spherical casting mold is formed, an eccentric protrusion 6 is formed in the hollow cavity 5 of the wear-resistant steel ball body 1, so that the wear-resistant steel ball body 1 can move in different trajectories when rotating in the ball mill, preventing the concentrated grinding of the material in a certain area, realizing the uniform grinding of the material, and improving the grinding effect.

[0023] A preparation process of a high-hardness chromium alloy wear-resistant steel ball includes the following processes: S1: Put waste steel, ferromolybdenum, and low-carbon ferromanganese into a melting furnace according to a certain weight ratio for melting. Control the melting temperature in the furnace at 1680 °C. After the raw materials in the melting furnace are completely melted, then put ferrochrome, ferronickel, ferrosilicon, cobalt oxide, titanium oxide, as well as borax and some rare earth oxides into it for melting, keep warm for 5.0 min, and stir the molten liquid after melting is completed, sample and adjust the content of each element in the molten liquid to obtain a uniform basic casting liquid; S2: Make a spherical core, place the spherical core in a spherical casting mold, combine the casting molds loaded with the spherical core to form a closed casting space, introduce the basic casting molten liquid into the casting mold in batches, set the interval time between batches at 3.0 min, and set the casting temperature at 1250 °C; S3: During the batch casting process, make the casting mold rotate at a high speed, and use the centrifugal force to make the basic casting molten liquid evenly adhere to the inner wall of the mold to form a hollow spherical structure. After casting is completed, take out the spherical core in the casting mold to obtain a rough product of wear-resistant steel balls; S4: After taking out the rough product of wear-resistant steel balls from the casting mold, send it into a quenching furnace to heat to 900 °C and keep warm. After keeping warm, perform a primary quenching, then heat the wear-resistant steel balls to 1050 °C again and keep warm. After keeping warm, perform a secondary quenching. Finally, send the quenched wear-resistant steel balls into a tempering furnace for tempering treatment and keep warm, and naturally cool in the air to obtain the finished product of wear-resistant steel balls; S5: Coat the surface of the finished product of wear-resistant steel balls with a wear-resistant coating made of titanium nitride by means of material vapor deposition.

[0024] The material of the spherical core is silicon carbide ceramic or aluminum nitride ceramic. An arc-shaped groove is provided on the annular side wall of the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. A process hole is provided on the spherical casting mold. The spherical core can be taken out through the process hole after casting is completed. The high-speed rotation of the casting mold is carried out on a high-speed rotating machine. Example

[0025] Refer to Figures 1-3 As shown, a high-hardness chromium alloy wear-resistant steel ball includes a wear-resistant steel ball body 1. The wear-resistant steel ball body 1 includes the following elements by weight percentage: carbon content: 2.0 wt%, silicon oxide content: 1.0 wt%, manganese oxide content: 1.4 wt%, chromium content: 23.0 wt%, nickel oxide content: 0.10 wt%, cobalt oxide content: 0.20 wt%, molybdenum oxide content: 0.15 wt%, boron oxide content: 0.12 wt%, titanium oxide content: 0.14 wt%, and the balance is Fe and unavoidable impurities, and also includes a small amount of rare earth oxides.

[0026] The wear-resistant steel ball body 1 is composed of a high-chromium wear-resistant base layer 2, a high-chromium wear-resistant outer layer 3, and a wear-resistant coating 4. The high-chromium wear-resistant base layer 2 is the innermost layer of the wear-resistant steel ball body 1, and the high-chromium wear-resistant outer layer 3 is the outermost layer of the wear-resistant steel ball body 1. The wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3. The high-chromium wear-resistant base layer 2 and the high-chromium wear-resistant outer layer 3, together with the wear-resistant coating material, form the wear-resistant coating 4 by means of material vapor deposition, which improves the wear resistance of the wear-resistant steel ball body 1 and extends its service life. A hollow cavity 5 is provided in the high-chromium wear-resistant base layer 2, and an eccentric protrusion 6 is provided on the annular inner wall of the hollow cavity 5. The cross-section of the eccentric protrusion 6 is arc-shaped. The high-chromium wear-resistant base layer 2, the high-chromium wear-resistant outer layer 3, and the eccentric protrusion 6 are integrally cast. The material of the wear-resistant coating 4 is titanium nitride, and the wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3 by means of material vapor deposition. An arc-shaped groove is provided on the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. After the spherical casting mold is cast and formed, the eccentric protrusion 6 is formed in the hollow cavity 5 of the wear-resistant steel ball body 1, so that the wear-resistant steel ball body 1 can move along different trajectories when rotating in the ball mill, preventing the concentrated grinding of the material in a certain area and realizing the uniform grinding of the material, thereby improving the grinding effect.

[0027] A preparation process of a high-hardness chromium alloy wear-resistant steel ball includes the following steps: S1: Put waste steel, ferromolybdenum, and low-carbon ferromanganese into a hot-melt furnace according to a certain weight ratio for melting. The melting temperature in the furnace is controlled at 1700 °C. After the raw materials in the hot-melt furnace are completely melted, then put ferrochromium, ferronickel, ferrosilicon, cobalt oxide, and titanium oxide, as well as borax and some rare earth oxides into it for melting, keep warm for 7.0 min, and stir the molten liquid after melting is completed, take samples and adjust the content of each element in the molten liquid to obtain a uniform basic casting liquid; S2: Make a spherical core, place the spherical core in a spherical casting mold, and form a closed casting space after combining the casting molds loaded with the spherical core. Pour the basic casting molten liquid into the casting mold in batches, and set the interval time between batches at 5.0 min, and set the casting temperature at 1350 °C; S3: During the batch casting process, make the casting mold rotate at a high speed, and use the centrifugal force to make the basic casting molten liquid evenly adhere to the inner wall of the mold to form a hollow spherical structure. After casting is completed, take out the spherical core in the casting mold to obtain the rough wear-resistant steel ball; S4: After taking out the rough wear-resistant steel ball from the casting mold, send it into a quenching furnace to heat it to 950 °C and keep it warm. After keeping warm, perform a first quenching, then heat the wear-resistant steel ball to 1100 °C again and keep it warm. After keeping warm, perform a second quenching. Finally, send the quenched wear-resistant steel ball into a tempering furnace for tempering treatment and keep it warm, and then naturally cool it in the air to obtain the finished wear-resistant steel ball; S5: Coat the surface of the finished wear-resistant steel ball with wear-resistant coating made of titanium nitride by means of physical vapor deposition of materials.

[0028] The spherical core is made of silicon carbide ceramic or aluminum nitride ceramic. An arc-shaped groove is provided on the annular side wall of the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. A process hole is provided on the spherical casting mold. The spherical core can be taken out through the process hole after casting is completed. The high-speed rotation of the casting mold is carried out on a high-speed rotating machine. Embodiment

[0029] Refer to Figures 1-3 As shown, a high-hardness chromium alloy wear-resistant steel ball includes a wear-resistant steel ball body 1. The wear-resistant steel ball body 1 includes the following elements by weight percentage: carbon content: 2.5wt%, silicon oxide content: 1.1wt%, manganese oxide content: 1.5wt%, chromium content: 24.0wt%, nickel oxide content: 0.12wt%, cobalt oxide content: 0.20wt%, molybdenum oxide content: 0.15wt%, boron oxide content: 0.12wt%, titanium oxide content: 0.16wt%, and the balance is Fe and unavoidable impurities, and also includes a small amount of rare earth oxides.

[0030] The wear-resistant steel ball body 1 is composed of a high-chromium wear-resistant base layer 2, a high-chromium wear-resistant outer layer 3, and a wear-resistant coating 4. The high-chromium wear-resistant base layer 2 is the innermost layer of the wear-resistant steel ball body 1, and the high-chromium wear-resistant outer layer 3 is the outermost layer of the wear-resistant steel ball body 1. The wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3. The high-chromium wear-resistant base layer 2 and the high-chromium wear-resistant outer layer 3, together with the wear-resistant coating 4 formed by means of physical vapor deposition of materials, improve the wear resistance of the wear-resistant steel ball body 1 and extend the service life. A hollow cavity 5 is provided in the high-chromium wear-resistant base layer 2. An eccentric protrusion 6 is provided on the annular inner wall of the hollow cavity 5. The cross-section of the eccentric protrusion 6 is arc-shaped. The high-chromium wear-resistant base layer 2, the high-chromium wear-resistant outer layer 3, and the eccentric protrusion 6 are integrally cast. The material of the wear-resistant coating 4 is titanium nitride. The wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3 by means of physical vapor deposition. An arc-shaped groove is provided on the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. After the spherical casting mold is formed, an eccentric protrusion 6 is formed in the hollow cavity 5 of the wear-resistant steel ball body 1, so that the wear-resistant steel ball body 1 can move in different trajectories when rotating in the ball mill, preventing the concentrated grinding of the materials in a certain area and realizing the uniform grinding of the materials and improving the grinding effect.

[0031] A preparation process of a high-hardness chromium alloy wear-resistant steel ball includes the following processes: S1: Put waste steel, ferromolybdenum and ferromanganese into a melting furnace according to a certain weight ratio for melting. The melting temperature in the furnace is controlled at 1720 °C. After the raw materials in the melting furnace are completely melted, then put ferrochrome, ferronickel, ferrosilicon, cobalt oxide and titanium oxide, as well as borax and some rare earth oxides into it for melting, keep warm for 6.0 min, and stir the molten liquid after melting is completed, take samples and adjust the content of each element in the molten liquid to obtain a uniform basic casting liquid; S2: Make a spherical core, place the spherical core in a spherical casting mold, combine the casting molds loaded with the spherical core to form a closed casting space, introduce the basic casting molten liquid into the casting mold in batches, set the interval time between batches at 5.0 min, and set the casting temperature at 1450 °C; S3: During the batch casting process, make the casting mold rotate at a high speed, and use centrifugal force to make the basic casting molten liquid evenly adhere to the inner wall of the mold to form a hollow spherical structure. After casting is completed, take out the spherical core in the casting mold to obtain a rough product of wear-resistant steel balls; S4: After taking out the rough product of wear-resistant steel balls from the casting mold, send it into a quenching furnace to heat to 1000 °C and keep warm. After keeping warm, perform a primary quenching, then heat the wear-resistant steel balls to 1150 °C again and keep warm. After keeping warm, perform a secondary quenching. Finally, send the quenched wear-resistant steel balls into a tempering furnace for tempering treatment and keep warm, and naturally cool in the air to obtain the finished product of wear-resistant steel balls; S5: Cover the surface of the finished product of wear-resistant steel balls with wear-resistant coating made of titanium nitride by means of physical vapor deposition of materials.

[0032] The material of the spherical core is silicon carbide ceramic or aluminum nitride ceramic. An arc-shaped groove is provided on the annular side wall of the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. A process hole is provided on the spherical casting mold. The spherical core can be taken out through the process hole after casting is completed. The high-speed rotation of the casting mold is carried out on a high-speed rotating machine. Example

[0033] Refer to Figures 1-3 As shown, a high-hardness chromium alloy wear-resistant steel ball includes a wear-resistant steel ball body 1. The wear-resistant steel ball body 1 includes the following elements by weight percentage: carbon content: 3.0 wt%, silicon oxide content: 1.4 wt%, manganese oxide content: 2.2 wt%, chromium content: 26.0 wt%, nickel oxide content: 0.16 wt%, cobalt oxide content: 0.25 wt%, molybdenum oxide content: 0.20 wt%, boron oxide content: 0.15 wt%, titanium oxide content: 0.18 wt%, and the balance is Fe and inevitable impurities, and also includes a small amount of rare earth oxides.

[0034] The wear-resistant steel ball body 1 is composed of a high-chromium wear-resistant base layer 2, a high-chromium wear-resistant outer layer 3, and a wear-resistant coating 4. The high-chromium wear-resistant base layer 2 is the innermost layer of the wear-resistant steel ball body 1, and the high-chromium wear-resistant outer layer 3 is the outermost layer of the wear-resistant steel ball body 1. The wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3. The high-chromium wear-resistant base layer 2 and the high-chromium wear-resistant outer layer 3, together with the wear-resistant coating material, form the wear-resistant coating 4 by means of material vapor deposition, which improves the wear resistance of the wear-resistant steel ball body 1 and extends its service life. A hollow cavity 5 is provided in the high-chromium wear-resistant base layer 2, and an eccentric protrusion 6 is provided on the annular inner wall of the hollow cavity 5. The cross-section of the eccentric protrusion 6 is arc-shaped. The high-chromium wear-resistant base layer 2, the high-chromium wear-resistant outer layer 3, and the eccentric protrusion 6 are integrally cast. The material of the wear-resistant coating 4 is titanium nitride, and the wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3 by means of material vapor deposition. An arc-shaped groove is provided on the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. After the spherical casting mold is cast and formed, an eccentric protrusion 6 is formed in the hollow cavity 5 of the wear-resistant steel ball body 1, so that the wear-resistant steel ball body 1 can move in different trajectories when rotating in the ball mill, preventing the concentrated grinding of the material in a certain area and realizing the uniform grinding of the material and improving the grinding effect.

[0035] A preparation process of a high-hardness chromium alloy wear-resistant steel ball includes the following processes: S1: Put waste steel, ferromolybdenum, and low-carbon ferromanganese into a melting furnace according to a certain weight ratio for melting. The melting temperature in the melting furnace is controlled at 1740 °C. After the raw materials in the melting furnace are completely melted, then put ferrochromium, ferronickel, ferrosilicon, cobalt oxide, and titanium oxide, as well as borax and some rare earth oxides into it for melting, keep warm for 10.0 min, and stir the molten liquid after the melting is completed, take samples and adjust the content of each element in the molten liquid to obtain a uniform basic casting liquid; S2: Make a spherical core, place the spherical core in a spherical casting mold, and form a closed casting space after combining the casting molds loaded with the spherical core. Gradually introduce the basic casting molten liquid into the casting mold, and set the interval time between each introduction at 7.0 min, and set the casting temperature at 1550 °C; S3: During the process of gradual casting, make the casting mold rotate at a high speed, and use the centrifugal force to make the basic casting molten liquid evenly adhere to the inner wall of the mold to form a hollow spherical structure. After the casting is completed, take out the spherical core in the casting mold to obtain a rough wear-resistant steel ball; S4: After taking out the rough wear-resistant steel ball from the casting mold, send it into a quenching furnace to heat it to 1050 °C and keep it warm. After keeping warm, perform a primary quenching, then heat the wear-resistant steel ball to 1200 °C again and keep it warm. After keeping warm, perform a secondary quenching. Finally, send the quenched wear-resistant steel ball into a tempering furnace for tempering treatment and keep it warm, and naturally cool it in the air to obtain the finished wear-resistant steel ball; S5: Coat the surface of the finished wear-resistant steel ball with wear-resistant coating made of titanium nitride by means of physical vapor deposition of materials.

[0036] The spherical core is made of silicon carbide ceramic or aluminum nitride ceramic. An arc-shaped groove is provided on the annular side wall of the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. A process hole is provided on the spherical casting mold. The spherical core can be taken out through the process hole after casting. The high-speed rotation of the casting mold is carried out on a high-speed rotating machine. Embodiment

[0037] Reference Figures 1-3 As shown, a high-hardness chromium alloy wear-resistant steel ball includes a wear-resistant steel ball body 1. The wear-resistant steel ball body 1 comprises elements with the following weight percentages: carbon content: 3.5 wt%, silicon oxide content: 1.6 wt%, manganese oxide content: 2.6 wt%, chromium content: 26.0 wt%, nickel oxide content: 0.16 wt%, cobalt oxide content: 0.25 wt%, molybdenum oxide content: 0.20 wt%, boron oxide content: 0.15 wt%, titanium oxide content: 0.20 wt%, and the balance is Fe and unavoidable impurities, and also includes a small amount of rare earth oxides.

[0038] The wear-resistant steel ball body 1 is composed of a high-chromium wear-resistant base layer 2, a high-chromium wear-resistant outer layer 3 and a wear-resistant coating 4. The high-chromium wear-resistant base layer 2 is the innermost layer of the wear-resistant steel ball body 1, and the high-chromium wear-resistant outer layer 3 is the outermost layer of the wear-resistant steel ball body 1. The wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3. The high-chromium wear-resistant base layer 2 and the high-chromium wear-resistant outer layer 3, together with the wear-resistant coating 4 formed by means of physical vapor deposition of materials, improve the wear resistance of the wear-resistant steel ball body 1 and extend its service life. A hollow cavity 5 is provided in the high-chromium wear-resistant base layer 2. An eccentric protrusion 6 is provided on the annular inner wall of the hollow cavity 5. The cross-section of the eccentric protrusion 6 is arranged in an arc shape. The high-chromium wear-resistant base layer 2, the high-chromium wear-resistant outer layer 3 and the eccentric protrusion 6 are integrally formed by casting. The material of the wear-resistant coating 4 is titanium nitride. The wear-resistant coating 4 is covered on the surface of the high-chromium wear-resistant outer layer 3 by means of physical vapor deposition. An arc-shaped groove is provided on the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. After the spherical casting mold is formed, an eccentric protrusion 6 is formed in the hollow cavity 5 of the wear-resistant steel ball body 1, so that the wear-resistant steel ball body 1 can move along different trajectories when rotating in the ball mill, preventing the concentrated grinding of the materials in a certain area and realizing the uniform grinding of the materials and improving the grinding effect.

[0039] A preparation process of a high-hardness chromium alloy wear-resistant steel ball includes the following processes: S1: Put waste steel, ferromolybdenum, and low-carbon ferromanganese into a melting furnace according to a certain weight ratio for melting. The melting temperature in the furnace is controlled at 1760 °C. After the raw materials in the melting furnace are completely melted, then put ferrochrome, ferronickel, ferrosilicon, cobalt oxide, titanium oxide, as well as borax and some rare earth oxides into it for melting, keep it warm for 10.0 min, and stir the molten liquid after the melting is completed, take samples and adjust the content of each element in the molten liquid to obtain a uniform basic casting liquid; S2: Make a spherical core, place the spherical core in a spherical casting mold. After combining the casting molds loaded with the spherical core, form a closed casting space. Pour the basic casting molten liquid into the casting mold in batches, set the interval time between batches at 7.0 min, and set the casting temperature at 1650 °C; S3: During the batch casting process, make the casting mold rotate at a high speed, and use the centrifugal force to make the basic casting molten liquid evenly adhere to the inner wall of the mold to form a hollow spherical structure. After casting is completed, take out the spherical core in the casting mold to obtain a rough product of wear-resistant steel balls; S4: After taking out the rough product of wear-resistant steel balls from the casting mold, send it into a quenching furnace to heat it to 1100 °C and keep it warm. After keeping it warm, conduct a primary quenching. Then heat the wear-resistant steel balls to 1250 °C again and keep it warm. After keeping it warm, conduct a secondary quenching. Finally, send the quenched wear-resistant steel balls into a tempering furnace for tempering treatment and keep it warm, and then naturally cool it in the air to obtain the finished product of wear-resistant steel balls; S5: Cover the surface of the finished product of wear-resistant steel balls with a wear-resistant coating made of titanium nitride by means of physical vapor deposition of materials.

[0040] The material of the spherical core is silicon carbide ceramic or aluminum nitride ceramic. An arc-shaped groove is provided on the annular side wall of the spherical core, and the arc-shaped groove is exposed in the spherical casting mold. A process hole is provided on the spherical casting mold. The spherical core can be taken out through the process hole after casting is completed. The high-speed rotation of the casting mold is carried out on a high-speed rotating machine.

[0041] In summary, Example 3 is the best example, which is superior to other examples in terms of efficiency, cost-effectiveness, and practicality.

[0042] When the present invention is in use, a spherical core is fabricated and placed in a spherical casting mold. The casting mold loaded with the spherical core is combined to form a closed casting space. The basic casting molten liquid is introduced into the casting mold in batches. During the batch casting process, the casting mold is rotated at a high speed. The centrifugal force is utilized to make the basic casting molten liquid evenly adhere to the inner wall of the mold, forming a hollow spherical structure. After casting is completed, the spherical core in the casting mold is taken out to form the high-chromium wear-resistant base layer 2 and the high-chromium wear-resistant outer layer 3. The wear-resistant coating made of titanium nitride is covered on the surface of the high-chromium wear-resistant outer layer 3 by means of physical vapor deposition of materials, so as to improve the wear resistance of the wear-resistant steel ball body 1 and extend the service life. By providing arc-shaped grooves on the spherical core and making the arc-shaped grooves exposed in the spherical casting mold, after the spherical casting mold is formed, eccentric protrusions 6 are formed in the hollow cavity 5 of the wear-resistant steel ball body 1, so that the wear-resistant steel ball body 1 can move along different trajectories when rotating in the ball mill, preventing the concentrated grinding of materials in a certain area and realizing the uniform grinding of materials, thereby improving the grinding effect.

[0043] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. A high-hardness chromium alloy wear-resistant steel ball, comprising a wear-resistant steel ball body (1), characterized in that: The wear-resistant steel ball body (1) comprises the following elements in weight percentage: carbon content: 1.5-3.5wt%, silicon oxide content: 0.8-1.6wt%, manganese oxide content: 1.0-2.6wt%, chromium content: 22.0-26.0wt%, nickel oxide content: 0.08-0.16wt%, cobalt oxide content: 0.15-0.25wt%, molybdenum oxide content: 0.10-0.20wt%, boron oxide content: 0.10-0.15wt%, titanium oxide content: 0.12-0.20wt%, and the balance is Fe and unavoidable impurities, and also includes a small amount of rare earth oxides.

2. The wear-resistant steel ball body (1) is composed of a high-chromium wear-resistant base layer (2), a high-chromium wear-resistant outer layer (3) and a wear-resistant coating (4), wherein the high-chromium wear-resistant base layer (2) is the innermost layer of the wear-resistant steel ball body (1), the high-chromium wear-resistant outer layer (3) is the outermost layer of the wear-resistant steel ball body (1), and the wear-resistant coating (4) is covered on the surface of the high-chromium wear-resistant outer layer (3).

3. The high-hardness chromium alloy wear-resistant steel ball according to claim 1, characterized in that: A hollow cavity (5) is provided in the high-chromium wear-resistant base layer (2), an eccentric protrusion (6) is provided on the annular inner wall of the hollow cavity (5), and the cross section of the eccentric protrusion (6) is arranged in an arc shape.

4. The high-hardness chromium alloy wear-resistant steel ball according to claim 1, characterized in that: The high-chromium wear-resistant base layer (2), the high-chromium wear-resistant outer layer (3) and the eccentric protrusion (6) are formed by integral casting.

5. The high-hardness chromium alloy wear-resistant steel ball according to claim 1, characterized in that: The material of the wear-resistant coating (4) is titanium nitride, and the wear-resistant coating (4) is covered on the surface of the high-chromium wear-resistant outer layer (3) by material vapor deposition.

6. A process for preparing a high-hardness chromium alloy wear-resistant steel ball according to any one of claims 1 to 4, characterized in that: The following processes are included: S1: Put the scrap steel, ferromolybdenum and low-carbon ferromanganese into a hot melting furnace in a certain weight ratio for melting. The melting temperature in the melting furnace is controlled at 1680-1760°C. After the raw materials in the hot melting furnace are completely melted, ferrochrome, ferronickel, ferrosilicon, cobalt oxide and titanium oxide, as well as borax and some rare earth oxides are put into the hot melting furnace for melting. The temperature is kept for 5.0-10.0 minutes. The melt after melting is stirred, and the content of each element in the melt is sampled and adjusted to obtain a uniform basic casting liquid. S2: making a spherical core, placing the spherical core in a spherical casting mold, combining the casting mold loaded with the spherical core to form a closed casting space, introducing the basic casting melt into the casting mold in batches, with the interval time of each batch set at 3.0-7.0 minutes, and the casting temperature set at 1250-1650°C; S3: During the stepwise casting process, the casting mold is rotated at a high speed, and the basic casting melt is uniformly attached to the inner wall of the mold by centrifugal force to form a hollow spherical structure. After the casting is completed, the spherical core in the casting mold is taken out to obtain a rough wear-resistant steel ball; S4: After taking out the rough wear-resistant steel ball from the casting mold, send it into a quenching furnace, heat it to 900-1100°C and keep it warm, perform a quenching after keeping it warm, then heat the wear-resistant steel ball again to 1050-1250°C and keep it warm, perform a second quenching after keeping it warm, and finally send the quenched wear-resistant steel ball into a tempering furnace for tempering treatment and keep it warm, and naturally cool it in the air to obtain a finished wear-resistant steel ball; S5: The wear-resistant coating made of titanium nitride is coated on the surface of the wear-resistant steel ball product by material vapor deposition.

7. The high-hardness chromium alloy wear-resistant steel ball and its preparation process according to claim 5, characterized in that: The material of the spherical core is silicon carbide ceramic or aluminum nitride ceramic. An arc-shaped groove is arranged on the annular side wall of the spherical core, and the arc-shaped groove is exposed in the spherical casting mold.

8. The high-hardness chromium alloy wear-resistant steel ball and its preparation process according to claim 5, characterized in that: The spherical casting mold is provided with a process hole, and the spherical core can be taken out through the process hole after the casting is completed.

9. The high-hardness chromium alloy wear-resistant steel ball and its preparation process according to claim 5, characterized in that: The high-speed rotation of the casting mold is performed on a high-speed rotating machine.

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