Wear-resistant alloy for seabed mining and method of manufacturing the same

Abstract

The present application relates to the technical field of metal material, and especially relates to a kind of wear-resistant alloy for seabed deposit mining and a manufacturing method thereof.The chemical composition of the wear-resistant alloy is as follows in terms of percentage by weight:Fe: 28.0%~28.4%;Cr: 26.0%~26.4%;Al: 13.4%~13.8%;Cu: 31.8%~32.2%;the balance is inevitable impurity elements, and the content of impurity elements is not more than 0.1%.The present application has the following beneficial effects:the hardness of the wear-resistant alloy is HRC≥52, the U-shaped notch impact energy at-20℃ is >20J, the seawater medium corrosion rate is 0.001~0.002mm / y, it has very high wear resistance, and it is suitable for use in marine environment.The manufacturing process is simple, the cost is relatively low, and it has broad development prospects.

Description

Technical Field

[0001] This invention relates to the field of metallic materials technology, and in particular to a wear-resistant alloy for mining seabed deposits and its manufacturing method. Background Technology

[0002] Since the beginning of the 21st century, with the increasing scarcity of land resources, the development of marine mineral resources has become extremely important. The ocean not only contains abundant energy resources such as oil, natural gas, and methane hydrate, but also rich metal deposits. Currently, marine energy development is in full swing, and the development of metal mineral resources is about to enter a large-scale era. In view of this, high-quality wear-resistant materials adapted to the harsh marine environment will undoubtedly usher in excellent development opportunities and a broad market. Currently, traditional wear-resistant materials do not possess the performance characteristics suitable for marine environments. Wear-resistant materials suitable for marine applications are all wear-resistant alloys containing expensive metal elements such as Co, Ni, Mo, V, Ti, and Nb, resulting in excessively high alloy costs. Therefore, the development of a marine wear-resistant alloy that is adaptable to the marine environment, possesses excellent wear resistance, and is reasonably priced is particularly urgent.

[0003] Chinese invention patent CN118516607A, entitled "A Method for Preparing Wear-Resistant Cast Steel," discloses a wear-resistant alloy and its preparation method, relating to the field of wear-resistant materials technology. By weight percentage, the wear-resistant alloy comprises: C 2-4 wt%, V 9-11 wt%, Cr 5-8 wt%, Mo 2-5 wt%, Mn 0.5-1.0 wt%, Si 0.5-1.0 wt%, Al 0.5-1.0 wt%, Ni 0.4-1.0 wt%, N 0.05-0.15 wt%, S ≤0.07 wt%, P ≤0.07 wt%, La+Ce 0.25-0.45 wt%, with the balance being Fe. The wear-resistant alloy of this invention exhibits higher hardness, better wear resistance, and excellent castability, while its processing and preparation method is simple. The alloy of this invention can be applied to key components in the metallurgical and mining fields and military equipment. However, this patent has no practical value in the development of marine resources because it has poor resistance to seawater corrosion and is not suitable for use in marine environments.

[0004] Chinese invention patent CN103114247A, entitled "A High-Hardness, High-Toughness, Wear-Resistant Steel and Its Preparation Method," discloses a high-hardness, high-toughness, wear-resistant steel with the following weight percentage composition: C 1-1.5%, Si 0.2-0.5%, Mn 10-12%, Cr 1.3-1.5%, V 0.1-0.3%, Ti 0.05-0.2%, and the balance being Fe. This invention improves the hardenability, hardenability, and mechanical properties of the material by controlling the content of the added alloying elements and the Mn / C ratio between 4.8 and 8.2. This allows castings made from this material to achieve a high-hardness martensitic structure and a bainitic structure with good overall performance in the as-cast state, exhibiting both high strength and excellent wear resistance. Furthermore, the manufacturing process is simple and the production cost is low. However, this patent is not applicable to marine resource development due to its poor resistance to seawater corrosion, making it unsuitable for use in marine environments.

[0005] Chinese invention patent CN117737509A, entitled "A GH5630C Wear-Resistant Alloy and Its Preparation Method and Application," discloses a GH5630C wear-resistant alloy comprising the following chemical composition: C 1.1–1.4%; Cr 28.5–31.5%; Ni 1.0–2.5%; W 4.5–5.5%; Mo 0.50–1.50%; Mn 0.50–1.70%; Si 0.20–1.50%; Nb 0.3–0.6%; La 0.02–0.2%; Fe ≤ 3.00%; S ≤ 0.03%; P ≤ 0.04%; with the balance being Co. This application also provides a method for preparing the GH5630C wear-resistant alloy. The GH5630C wear-resistant alloy of this application has a temperature resistance exceeding 500℃ and exhibits good wear resistance, impact toughness, and fatigue resistance, making it suitable for manufacturing bearing parts for high-temperature, oxygen-rich, or corrosive environments. However, the wear-resistant alloy in this application is suitable for wear-resistant bearing parts, but its corrosiveness is not suitable for marine environments, and it cannot be used in marine environments.

[0006] Chinese invention patent CN117020214A, entitled "A Preparation Method of a Boron-Iron-Based Wear-Resistant Alloy," provides a method for preparing a boron-iron-based wear-resistant alloy, comprising: mixing raw material powders according to the component percentages; ball milling the mixed powders; subjecting the ball-milled powders to plasma atomization treatment; melting the plasma-atomized powders, followed by deoxidation and slag removal treatment; after adjusting the temperature to 1500-1550℃, adding a modifier for modification treatment, and holding at the temperature for static treatment; and casting and cooling the static molten iron under vibration conditions. This invention's preparation method is simple to operate and has high production efficiency. The prepared boron-iron-based wear-resistant material exhibits significantly improved hardness, toughness, and wear resistance. However, its corrosion resistance is poor for marine environments, making it unsuitable for marine applications. Summary of the Invention

[0007] To overcome the shortcomings of existing technologies, this invention provides a wear-resistant alloy for seabed mining and its manufacturing method. It adopts an equimolar ratio multi-element alloy design, in which Fe, Cr, Al, and Cu can be used to obtain a single-structure wear-resistant alloy in the casting state. The wear-resistant alloy has a hardness of HRC≥52, and an impact energy of U-notch >20J at -20℃, exhibiting extremely high wear resistance. It is also suitable for use in marine environments. Its manufacturing process is simple, the cost is relatively low, and it has broad development prospects.

[0008] To achieve the above objectives, the present invention employs the following technical solution:

[0009] A wear-resistant alloy for seabed mining, wherein the chemical composition of the wear-resistant alloy by weight percentage is as follows: Fe: 28.0%~28.4%; Cr: 26.0%~26.4%; Al: 13.4%~13.8%; Cu: 31.8%~32.2%; the balance being unavoidable impurity elements, the content of which is not greater than 0.1%.

[0010] The rationale for the chemical composition design of this invention is explained in detail below:

[0011] A solid solution with a single structure and large lattice distortion can only be formed when the configuration entropy of the alloy system reaches its maximum. Therefore, the condition of high configuration entropy can only be met when the molar ratio of the atoms of each component is close to 1. Thus, the requirements for chemical composition in this invention are relatively strict.

[0012] Fe is a common and economical alloying element. It easily forms solid solutions with many elements, has high corrosion resistance, and can also improve the wear resistance of alloys. The Fe content should be controlled between 28.0% and 28.4%.

[0013] Cr is a periodic element of Fe and readily forms solid solutions with iron. At the same time, chromium is an excellent corrosion-resistant element that can greatly improve the steel's resistance to seawater corrosion and its wear resistance. Cr should be controlled at 26.0% to 26.4%.

[0014] Compared to other elements, Al has significantly different atomic radii and electronegativity. When it forms a solid solution, it can increase lattice distortion and improve the hardness of the alloy. Furthermore, aluminum can significantly reduce the density of the alloy, with Al content controlled between 13.4% and 13.8%.

[0015] Cu is chemically stable and can improve the thermal conductivity of steel, thereby increasing the cooling rate during alloy solidification and facilitating the formation of a single-structure solid solution. Cu can also significantly improve the toughness of the alloy; the Cu content should be controlled between 31.8% and 32.2%.

[0016] Furthermore, the Fe, Cr, Al, and Cu are selected as pure metallic elements with a purity of 99.9% or as alloys with an adjusted molar ratio of 1 for each element.

[0017] Furthermore, the wear-resistant alloy has a hardness of HRC ≥ 52; an impact energy of U-notch at -20℃ > 20J; and a density < 6.6g / cm³. 3 Corrosion rate in seawater medium: 0.001–0.002 mm / y.

[0018] Furthermore, the manufacturing process of the wear-resistant alloy is as follows: smelting → casting → tempering.

[0019] Smelting process: Vacuum smelting is carried out in an electric furnace at a temperature of 1300℃~1450℃. After the alloy is fully melted, it is held at the temperature for 5~10 minutes before casting.

[0020] Casting process: casting thickness d≤150mm; pouring temperature 1350℃~1400℃; demolding when mold surface temperature <100℃;

[0021] Tempering process: The casting is heated to 300℃~350℃ in the furnace and held for 10~15 minutes.

[0022] Furthermore, the casting process employs a metal mold, with graphite sprayed into the mold and then baked.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1) Fe, Cr, Al, and Cu can be used to obtain wear-resistant alloys with a single structure in the casting state. Moreover, their cost is relatively low, the manufacturing process is simple, and they have broad development prospects.

[0025] 2) The wear-resistant alloy of this composition has high hardness and high toughness, with a hardness of HRC≥52 and an impact energy of U-notch at -20℃>20J, thus exhibiting good wear resistance.

[0026] 3) Compared with ordinary wear-resistant alloys, this alloy has a lower density of <6.6 g / cm³. 3 It has good resistance to seawater corrosion, with a seawater corrosion rate of 0.001~0.002mm / y, making it suitable for use in marine environments.

[0027] 4) The heat treatment process is simple and saves energy. Detailed Implementation

[0028] The specific embodiments of the present invention will be further described below:

[0029] Example: This invention employs an equimolar ratio multi-element alloy design. A qualified alloy melt is smelted in a vacuum electric furnace at a temperature of 1400℃~1450℃. After the alloy is fully melted, it is held at this temperature for 5~10 minutes. Casting begins when the alloy melt cools to 1350~1400℃. The mold is demolded when the mold surface temperature is <100℃. The casting surface is cleaned and visually inspected for quality after cooling to room temperature. The casting is then placed in a heating furnace, heated to 300~350℃, held for 10~15 minutes, and then cooled in the furnace. Specific alloy compositions for the five embodiments of this invention are shown in Table 1, heat treatment process parameters for the castings are shown in Table 2, and various performance indicators of the wear-resistant alloy are shown in Table 3.

[0030] Table 1. Specific alloy compositions (wt, %) of embodiments of the present invention:

[0031]

[0032] Table 2 Heat treatment process parameters for castings in embodiments of the present invention:

[0033]

[0034] Table 3. Performance indicators of the wear-resistant alloy in the embodiments of the present invention:

[0035]

[0036] The above embodiments demonstrate that the wear-resistant alloy of this composition possesses high hardness and high toughness, with a hardness HRC≥52, and an impact energy of >20J at -20℃ and a U-notch impact energy, thus exhibiting good wear resistance and a low density <6.6g / cm³. 3 It has good resistance to seawater corrosion, with a seawater corrosion rate of 0.001 to 0.002 mm / y, where mm / y represents the thickness corroded per year, making it suitable for use in marine environments.

[0037] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A wear-resistant alloy for seabed mining, characterized in that, The chemical composition of the wear-resistant alloy, by weight percentage, is as follows: Fe: 28.0%–28.4%; Cr: 26.0%–26.4%; Al: 13.4%–13.8%; Cu: 31.8%–32.2%; the balance being unavoidable impurities, with an impurity content not exceeding 0.1%. The wear-resistant alloy has a hardness HRC ≥ 52; U-notch impact energy at -20℃ > 20J; and a density < 6.6 g / cm³. 3 The corrosion rate in seawater is 0.001 to 0.002 mm / y.

2. The wear-resistant alloy for seabed mining according to claim 1, characterized in that, The Fe, Cr, Al, and Cu are selected as pure metallic elements with a purity of 99.9% or as alloys with an adjusted molar ratio of 1 for each element.

3. A method for manufacturing a wear-resistant alloy for seabed mining according to claim 1, characterized in that, The manufacturing process of the wear-resistant alloy is as follows: smelting → casting → tempering. Smelting process: Vacuum smelting is carried out in an electric furnace at a temperature of 1300℃~1450℃. After the alloy is fully melted, it is held at the temperature for 5~10 minutes before casting. Casting process: casting thickness d≤150mm; pouring temperature 1350℃~1400℃; demolding when mold surface temperature <100℃; Tempering process: The casting is heated to 300℃~350℃ in the furnace and held for 10~15 minutes.

4. The method for manufacturing the wear-resistant alloy for seabed mining according to claim 3, characterized in that, The casting process uses a metal mold, with graphite sprayed into the mold and then baked.

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