High-chromium alloy material, slurry pump and preparation method of high-chromium alloy material

Abstract

The invention relates to the technical field of slurry pump materials, in particular to a high-chromium alloy material, a slurry pump and a preparation method of the slurry pump. The high-chromium alloy material comprises the following components in percentage by mass: 2.8%-3.0% of C, 0.5%-0.7% of Mn, 26%-30% of Cr, 2%-2.5% of Ni, 1.5%-2.8% of Mo, 0.9%-1.2% of Cu, 0.05%-0.10% of Gd, 1%-3% of Ti and the balance of Fe and inevitable impurities. The alloy material takes iron as a matrix, chromium and C generate chromium carbide, chromium and oxygen on the surface form a compact oxidation film, and the alloy material is resistant to high-temperature oxidation and corrosion. Nickel improves the corrosion resistance of the alloy in chloride, manganese reduces hot brittleness, Ni provides good high-temperature strength and toughness for the material, molybdenum and copper improve the acid corrosion resistance of the alloy, Gd improves the heat acid corrosion resistance of the alloy, and Ti enhances the hardness of the material. The slurry pump prepared from the high-chromium alloy material has good wear resistance and hot and acid corrosion resistance.

Description

Technical Field

[0001] This application relates to the technical field of slurry pump materials, and particularly relates to a high-chromium alloy material, a slurry pump and a preparation method thereof. Background Art

[0002] Slurry pumps are mainly applicable to industries such as mines, power plants, dredging, metallurgy, chemicals, building materials and petroleum. For example: in the mining industry, slurry pumps are used to transport the slurry containing abrasive solid particles generated during the beneficiation process; in the power industry, slurry pumps are used to handle boiler slag discharge and high-concentration ash slurry; in the metallurgy industry, slurry pumps are used to separate blast furnace molten slag and metal liquid to ensure the continuity of smelting; in the chemical industry, slurry pumps are used to transport slurries containing crystals or corrosives. In these harsh industrial scenarios, the pump impellers, rotating shafts, etc. of slurry pumps are subjected to multiple tests of high temperature, friction and acid corrosion for a long time, with a short service life, easy to be damaged, and high operation and maintenance costs. Summary of the Invention

[0003] In view of the problem that the current slurry pumps are not strong enough in withstanding high temperature, friction and acid corrosion, this application proposes a high-chromium alloy material, a slurry pump and a preparation method thereof to solve this problem.

[0004] In the first aspect, this application proposes a high-chromium alloy material and adopts the following technical solutions.

[0005] A high-chromium alloy material comprises components in the following mass percentages: C: 2.8 - 3.0%, Mn: 0.5 - 0.7%, Cr: 26 - 30%, Ni: 2 - 2.5%, Mo: 1.5 - 2.8%, Cu: 0.9 - 1.2%, Gd: 0.05 - 0.10%, Ti: 1 - 3%, the balance being Fe and inevitable impurities.

[0006] By adopting the above technical solutions, for the alloy material with the above proportions, with iron as the matrix and a high proportion of chromium added, chromium mainly exists in the form of solid solution, part of chromium reacts with C to form chromium carbide, and the surface chromium and oxygen form a dense oxide film, which is resistant to high-temperature oxidation and corrosion. The addition of nickel improves the alloy's resistance to pitting corrosion and crevice corrosion in chloride media, thereby enhancing its corrosion resistance. Manganese efficiently combines with the impurity sulfur to form high-melting-point MnS, reducing the thermal brittleness caused by the precipitation of FeS at grain boundaries and improving the high-temperature processing performance of the material. Ni provides good high-temperature strength and toughness for the material, improving wear resistance and crack resistance. The addition of molybdenum enhances the alloy's corrosion resistance in acidic media, especially having a significant effect on resistance to pitting corrosion and crevice corrosion. The addition of copper improves the alloy's corrosion resistance in acid. Gd improves the alloy's resistance to heat-acid corrosion. Ti and C form TiC, enhancing the material hardness. A preferred solution for the high-chromium alloy material is that in the high-chromium alloy material: the Si content is ≤0.8%, the P content is ≤1%, and the S content is ≤0.06%.

[0007] By adopting the above technical solution, since excessive Si may reduce toughness, phosphorus is prone to segregate at grain boundaries during solidification, forming low-melting-point phosphide eutectics (such as Fe3P), significantly reducing the toughness of the alloy, especially reducing the low-temperature impact toughness. During the casting process, the phosphide eutectics will reduce the thermal strength of the alloy and increase the risk of thermal cracks. Moreover, sulfur will form low-melting-point FeS with iron, which is prone to melting at grain boundaries during hot working, triggering thermal cracks. Therefore, controlling the contents of Si, P, and S at the above lower levels can maintain good toughness of the material and prevent thermal cracks from occurring during the casting process due to this factor.

[0008] In a second aspect, the present application proposes a preparation method for a slurry pump and adopts the following technical solution.

[0009] A preparation method for a slurry pump, the preparation method comprising: S1, mixing metal raw materials and alloy raw materials according to the component ratio of the high-chromium alloy material, melting the metal raw materials and alloy raw materials to obtain a metal liquid.

[0010] S2, casting the metal liquid into a mold to obtain a blank, and annealing the blank to obtain the slurry pump.

[0011] By adopting the above technical solution, each component is melted into one body, and the slurry pump obtained through casting and annealing has good wear resistance, high-temperature resistance, and acid resistance.

[0012] A preferred solution for the preparation method of the slurry pump is that step S1 includes: adding a mixed raw material composed of a carbonizing agent, pure iron, ferromanganese carbon, ferronickel, copper, gadolinium, ferromolybdenum, ferrotitanium, and ferromanganese chromium into a smelting furnace, heating and melting to obtain the metal liquid.

[0013] By adopting the above technical solution, the costs of these metals and alloys are relatively low, and their melting points are relatively close, making it easy to heat and melt them batch by batch at relatively close temperatures, thus improving the preparation efficiency.

[0014] A preferred embodiment of the preparation method of the slurry pump is as follows: by mass, the proportion of the recarburizer in the mixed raw materials is 0.45-0.78%; the proportion of the pure iron in the mixed raw materials is 28.92-32.6%; the carbon manganese iron contains 50-70% manganese and 2-5% carbon, and the proportion of the carbon manganese iron in the mixed raw materials is 1%; the nickel iron contains 20-25% nickel, and the proportion of the nickel iron in the mixed raw materials is 10%; the proportion of the copper in the mixed raw materials is 0.9-1.2%; the proportion of the gadolinium in the mixed raw materials is 0.05-0.10%; the ferromolybdenum contains 50-70% molybdenum, and the proportion of the ferromolybdenum in the mixed raw materials is 3-4%; the ferrotitanium contains 50-75% titanium, and the proportion of the ferrotitanium in the mixed raw materials is 2-4%; the carbon chromium iron contains 52-60% chromium and 4-5% carbon, and the proportion of the carbon chromium iron in the mixed raw materials is 50%.

[0015] By adopting the above technical solution, the alloy material and the slurry pump prepared from the combination of various elements with the above content ratios have good hardness, toughness and acid resistance, and good heat resistance and friction resistance.

[0016] A preferred embodiment of the preparation method of the slurry pump is that step S1 specifically includes: first adding pure iron into the melting furnace and heating it to 1540-1600°C to completely melt the pure iron; then adding carbon manganese iron, nickel iron, copper and gadolinium into the melting furnace, and adding the recarburizer after all are melted and dispersing the recarburizer evenly; finally adding ferromolybdenum, ferrotitanium and carbon chromium iron into the melting furnace and heating it to 1860-1900°C to completely melt the raw materials and obtain the molten metal.

[0017] By adopting the above technical solution, first melt the pure iron (melting point 1539°C) matrix at a relatively low temperature, and then add carbon manganese iron (melting point 1300°C), nickel iron (melting point 1480°C), copper (melting point 1085°C) and gadolinium (melting point 1313°C) to make them disperse evenly in the pure iron matrix, so as to avoid uneven dispersion of carbon manganese iron, nickel iron, copper and gadolinium that may occur when added simultaneously with pure iron. Then add the recarburizer and disperse it evenly in the matrix, and then melt ferromolybdenum (melting point 1750°C), ferrotitanium (melting point 1677°C) and carbon chromium iron (melting point 1860°C) at a relatively high temperature. It is not necessary to maintain a high temperature of 1860-1900°C throughout the process, reducing energy consumption.

[0018] A preferred embodiment of the preparation method of the slurry pump is that the annealing in step S2 is: heating the embryo cooled to room temperature to 600-700°C and holding for 1-2 h, then heating up to 900-1000°C and holding for 1-2 h, then cooling down to 400-500°C and holding for 1-2 h, and finally cooling to room temperature.

[0019] By adopting the above technical solution, through annealing treatment, the brittleness of the metal is reduced, and its characteristics of enhanced plastic deformation without cracking are improved.

[0020] In a third aspect, the present application provides a slurry pump, and the following technical solution is adopted.

[0021] A slurry pump is prepared according to the preparation method of the slurry pump described above.

[0022] By adopting the above technical solution, the slurry pump has good heat resistance, resistance to slurry friction and acid resistance, and a long service life.

[0023] In summary, the slurry pump, high-chromium alloy material and its preparation method of the present application have the following beneficial effects: Based on iron matrix, a high content of chromium significantly enhances the oxidation resistance and corrosion resistance to strong acids and chloride ions of the alloy. Chromium can react with carbon to form high-hardness carbides, enhancing wear resistance, and controlling the carbon content at 2.8 - 3.0% to avoid brittleness. Manganese can combine with sulfur, reducing the reaction of sulfur and iron to form low-melting-point FeS, thus preventing the occurrence of the phenomenon of easy melting at grain boundaries during hot working (such as rolling and forging) and triggering thermal cracks. Nickel provides good high-temperature strength and toughness for the material, improving wear resistance and crack resistance. The addition of molybdenum enhances high-temperature strength and creep resistance. The addition of copper cooperates with molybdenum and nickel to improve the hardness, wear resistance and tensile strength of the material. Gadolinium has a very strong affinity for oxygen and sulfur, forming nano-scale rare earth compounds, which act as heterogeneous nucleation cores, promoting the heterogeneous nucleation of α-Fe or γ-austenite, inhibiting grain growth, refining grains, improving toughness, and enhancing wear resistance and corrosion resistance. Titanium has a very strong affinity for carbon, forming high-melting-point TiC particles, which act as heterogeneous nucleation cores, refining the solidification structure, making the structure refined, and enhancing the hardness and wear resistance of the material. Description of the Drawings

[0024] Figure 1 It is a schematic internal structure diagram of the slurry pump. Detailed Embodiments

[0025] The technical solutions in the embodiments are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of them. Based on the following embodiments, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0026] Embodiment 1 The slurry pump is prepared according to the following steps in this embodiment.

[0027] S1. First, add pure iron into the smelting furnace and heat it to 1570 °C to completely melt the pure iron. Then, add ferromanganese carbon, ferronickel, copper, and gadolinium into the smelting furnace at 1570 °C. After complete melting, add a carburizer, which is graphite powder, and disperse the carburizer evenly by stirring. Finally, add ferromolybdenum, ferrotitanium, and ferromanganese chromium into the smelting furnace and heat it to 1880 °C to completely melt the raw materials, obtaining a metal liquid. This metal liquid is a liquid high-chromium alloy material.

[0028] The above carburizer, pure iron, ferromanganese carbon, ferronickel, copper, gadolinium, ferromolybdenum, ferrotitanium, and ferromanganese chromium form a mixed raw material. The following are the specific element contents of each raw material and the mass percentages of each raw material in the mixed raw material.

[0029] The carburizer contains 100% carbon, and the proportion of the carburizer in the mixed raw material is 0.66%. The proportion of this part of carbon in the mixed raw material is 0.66%.

[0030] The pure iron contains 100% iron, and the proportion of the pure iron in the mixed raw material is 30.77%. The proportion of this part of iron in the mixed raw material is 30.77%.

[0031] The ferromanganese carbon contains 60% manganese and 3% carbon, and the proportion of the ferromanganese carbon in the mixed raw material is 1%. The proportion of manganese in the mixed raw material is 0.6%, and the proportion of this part of carbon in the mixed raw material is 0.03%.

[0032] The ferronickel contains 22% nickel, and the proportion of the ferronickel in the mixed raw material is 10%. The proportion of nickel in the mixed raw material is 2.2%.

[0033] The proportion of copper in the mixed raw material is 1.0%.

[0034] The proportion of gadolinium in the mixed raw material is 0.07%.

[0035] The ferromolybdenum contains 60% molybdenum, and the proportion of the ferromolybdenum in the mixed raw material is 3.5%. The proportion of molybdenum in the mixed raw material is 2.1%.

[0036] The ferrotitanium contains 60% titanium, and the proportion of the ferrotitanium in the mixed raw material is 3%. The proportion of titanium in the mixed raw material is 1.8%.

[0037] The ferromanganese chromium contains 56% chromium and 4.4% carbon, and the proportion of the ferromanganese chromium in the mixed raw material is 50%. The proportion of chromium in the mixed raw material is 28%. The proportion of this part of carbon in the mixed raw material is 2.2%.

[0038] The mass percentages of the components of the above high-chromium alloy material are as follows: C: 2.89%, Mn: 0.6%, Cr: 28%, Ni: 2.2%, Mo: 2.1%, Cu: 1.0%, Gd: 0.07%, Ti: 1.8%, the balance being Fe and inevitable impurities.

[0039] S2, Cast the molten metal into a mold and cool it to room temperature to obtain a blank. Anneal the blank to obtain a slurry pump. Among them, annealing is to heat the blank cooled to room temperature to 650 °C and hold for 1.5 h, then raise the temperature to 950 °C and hold for 1.5 h, then lower the temperature to 450 °C and hold for 1.5 h, and finally cool to room temperature.

[0040] Example 2 The slurry pump of this example is prepared according to the following steps.

[0041] S1, First, add pure iron to the melting furnace and heat it to 1540 °C to completely melt the pure iron. Then add ferromanganese carbon, ferronickel, copper and gadolinium to the melting furnace at 1540 °C. After complete melting, add a carbon additive, which is graphite powder, and disperse the carbon additive evenly by stirring. Finally, add ferromolybdenum, ferrotitanium and ferrochromium carbon to the melting furnace and heat it to 1860 °C to completely melt the raw materials to obtain molten metal. This molten metal is a liquid high-chromium alloy material.

[0042] The above carbon additive, pure iron, ferromanganese carbon, ferronickel, copper, gadolinium, ferromolybdenum, ferrotitanium and ferrochromium carbon constitute a mixed raw material. The following are the specific element contents of each raw material and the mass percentages of each raw material in the mixed raw material.

[0043] The carbon additive contains 100% carbon, and the proportion of the carbon additive in the mixed raw material is 0.45%. The proportion of this part of carbon in the mixed raw material is 0.45%.

[0044] Pure iron contains 100% iron, and the proportion of pure iron in the mixed raw material is 32.6%. The proportion of this part of iron in the mixed raw material is 32.6%.

[0045] Ferromanganese carbon contains 50% manganese and 5% carbon, and the proportion of ferromanganese carbon in the mixed raw material is 1%. The proportion of manganese in the mixed raw material is 0.5%, and the proportion of this part of carbon in the mixed raw material is 0.05%.

[0046] Ferronickel contains 20% nickel, and the proportion of ferronickel in the mixed raw material is 10%. The proportion of nickel in the mixed raw material is 2%.

[0047] The proportion of copper in the mixed raw material is 0.9%.

[0048] The proportion of gadolinium in the mixed raw material is 0.05%.

[0049] Ferromolybdenum contains 50% molybdenum, and the proportion of ferromolybdenum in the mixed raw materials is 3%. The proportion of molybdenum in the mixed raw materials is 1.5%.

[0050] Ferrotitanium contains 50% titanium, and the proportion of ferrotitanium in the mixed raw materials is 2%. The proportion of titanium in the mixed raw materials is 1%.

[0051] Carbon ferrochrome contains 52% chromium and 5% carbon. The proportion of carbon ferrochrome in the mixed raw materials is 50%. The proportion of chromium in the mixed raw materials is 26%, and the proportion of this part of carbon in the mixed raw materials is 2.5%.

[0052] The mass percentages of the components of the above high-chromium alloy materials are as follows: C: 3.0%, Mn: 0.5%, Cr: 26%, Ni: 2%, Mo: 1.5%, Cu: 0.9%, Gd: 0.05%, Ti: 1%, the balance is Fe and inevitable impurities.

[0053] S2, Cast the molten metal into a mold and cool it to room temperature to obtain a blank. Anneal the blank to obtain a slurry pump. Among them, annealing is to heat the blank cooled to room temperature to 600 °C and hold for 1 h, then raise the temperature to 900 °C and hold for 1 h, then lower the temperature to 400 °C and hold for 1 h, and finally cool to room temperature.

[0054] Example 3 This example prepares a slurry pump according to the following steps.

[0055] S1, First, add pure iron to the melting furnace and heat it to 1600 °C to completely melt the pure iron. Then add ferromanganese, ferronickel, copper and gadolinium to the melting furnace at 1600 °C. After all are melted, add a carbonaceous additive, which is graphite powder, and disperse the carbonaceous additive evenly by stirring. Finally, add ferromolybdenum, ferrotitanium and carbon ferrochrome to the melting furnace and heat to 1900 °C to completely melt the raw materials to obtain a molten metal. This molten metal is a liquid high-chromium alloy material.

[0056] The above carbonaceous additive, pure iron, ferromanganese, ferronickel, copper, gadolinium, ferromolybdenum, ferrotitanium and carbon ferrochrome constitute the mixed raw materials. The following are the specific element contents of each raw material and the mass proportion of each raw material in the mixed raw materials.

[0057] The carbonaceous additive contains 100% carbon, and the proportion of the carbonaceous additive in the mixed raw materials is 0.78%. The proportion of this part of carbon in the mixed raw materials is 0.78%.

[0058] Pure iron contains 100% iron, and the proportion of pure iron in the mixed raw materials is 28.92%. The proportion of this part of iron in the mixed raw materials is 28.92%.

[0059] Ferromanganese contains 70% manganese and 2% carbon. The proportion of ferromanganese in the mixed raw materials is 1%. The proportion of manganese in the mixed raw materials is 0.7%, and the proportion of this part of carbon in the mixed raw materials is 0.02%.

[0060] Ferronickel contains 25% nickel. The proportion of ferronickel in the mixed raw materials is 10%. The proportion of nickel in the mixed raw materials is 2.5%.

[0061] The proportion of copper in the mixed raw materials is 1.2%.

[0062] The proportion of gadolinium in the mixed raw materials is 0.10%.

[0063] Ferromolybdenum contains 70% molybdenum. The proportion of ferromolybdenum in the mixed raw materials is 4%. The proportion of molybdenum in the mixed raw materials is 2.8%.

[0064] Ferrotitanium contains 75% titanium. The proportion of ferrotitanium in the mixed raw materials is 4%. The proportion of titanium in the mixed raw materials is 3%.

[0065] Ferrochrome contains 60% chromium and 4% carbon. The proportion of ferrochrome in the mixed raw materials is 50%. The proportion of chromium in the mixed raw materials is 30%, and the proportion of this part of carbon in the mixed raw materials is 2%.

[0066] The mass percentages of the components of the above high-chromium alloy materials are statistically as follows: C: 2.8%, Mn: 0.7%, Cr: 30%, Ni: 2.5%, Mo: 2.8%, Cu: 1.2%, Gd: 0.10%, Ti: 3%, the balance being Fe and inevitable impurities.

[0067] S2, the molten metal is cast into shape and cooled to room temperature to obtain a blank. The blank is annealed to obtain a slurry pump. Among them, annealing is to heat the blank cooled to room temperature to 700 °C and hold for 2 h, then raise the temperature to 1000 °C and hold for 2 h, then lower the temperature to 500 °C and hold for 2 h, and finally cool to room temperature.

[0068] Comparative Example 1 In this comparative example, the slurry pump is prepared by the scheme of Example 1. The only difference between this comparative example and Example 1 is that: the mass percentage of C in the high-chromium alloy material is adjusted to 3.2%. The specific measures taken for this adjustment are: adjusting the proportion of the carbon additive in the mixed raw materials to 0.97%, and adjusting the proportion of pure iron in the mixed raw materials to 30.46%, then the mass percentage of C in the high-chromium alloy material becomes 3.2%.

[0069] Comparative Example 2 In this comparative example, the slurry pump was prepared using the solution of Example 1. The only difference between this comparative example and Example 1 is that the mass percentage of Mn in the high-chromium alloy material was adjusted to 0.9%. The specific measures taken for this adjustment were as follows: pure Mn was added, and the mass percentage of the added pure Mn in the high-chromium alloy material was 0.3%. Also, the input of pure iron was reduced, and the proportion of pure iron in the mixed raw materials dropped to 30.47%. In this way, the mass percentage of Mn in the high-chromium alloy material reached 0.9%.

[0070] Comparative Example 3 In this comparative example, the slurry pump was prepared using the solution of Example 1. The only difference between this comparative example and Example 1 is that the mass percentage of Ni in the high-chromium alloy material was adjusted to 1.1%. The specific measures taken for this adjustment were as follows: the proportion of ferronickel in the mixed raw materials was adjusted to 5%, and the proportion of pure iron in the mixed raw materials was adjusted to 35.77%. Then, the mass percentage of Ni in the high-chromium alloy material dropped to 1.1%.

[0071] Comparative Example 4 In this comparative example, the slurry pump was prepared using the solution of Example 1. The only difference between this comparative example and Example 1 is that the mass percentage of Mo in the high-chromium alloy material was adjusted to 1.2%. The specific measures taken for this adjustment were as follows: the proportion of ferromolybdenum in the mixed raw materials was adjusted to 2%, and the proportion of pure iron in the mixed raw materials was adjusted to 32.27%. Then, the proportion of molybdenum in the mixed raw materials was 1.2%.

[0072] Comparative Example 5 In this comparative example, the slurry pump was prepared using the solution of Example 1. The only difference between this comparative example and Example 1 is that the mass percentage of Cu in the high-chromium alloy material was adjusted to 0.6%. The specific measures taken for this adjustment were as follows: the proportion of copper in the mixed raw materials was adjusted to 0.6%, and the proportion of pure iron in the mixed raw materials was adjusted to 31.17%. Then, the proportion of copper in the mixed raw materials was 0.6%.

[0073] Comparative Example 6 In this comparative example, the slurry pump was prepared using the solution of Example 1. The only difference between this comparative example and Example 1 is that the mass percentage of Gd in the high-chromium alloy material was adjusted to 0.01%. The specific measures taken for this adjustment were as follows: the proportion of gadolinium in the mixed raw materials was adjusted to 0.01%, and the proportion of pure iron in the mixed raw materials was adjusted to 30.83%. Then, the proportion of gadolinium in the high-chromium alloy material was 0.01%.

[0074] Comparative Example 7 In this comparative example, the slurry pump was prepared using the solution of Example 1. The only difference between this comparative example and Example 1 was that the mass percentage of Ti in the high-chromium alloy material was adjusted to 0.3%. The specific measures taken for this adjustment were: adjusting the proportion of gadolinium in the mixed raw materials to 0.3%, and adjusting the proportion of pure iron in the mixed raw materials to 32.27%. Then, the mass percentage of Ti in the high-chromium alloy material was 0.3%.

[0075] Using X-ray fluorescence spectrometry to detect, in the high-chromium alloy materials of the above examples and comparative examples: the Si content ≤ 0.8%, the P content ≤ 1%, and the S content ≤ 0.06%.

[0076] Test Example 1 The high-chromium alloy materials of Examples 1 to 3 and Comparative Examples 1 to 7 were tested as follows.

[0077] Measure the Rockwell hardness HRC, and implement the standard 《GB / T17445-2022》.

[0078] Wear resistance test, implement the standard 《GB / T17445-2022》, and detect the weight loss rate of the grinding ball to be 0.1928 g / h.

[0079] Test the tensile strength σ b , and implement the standard 《GB / T 228.1-2021》.

[0080] Test the impact absorption work Aku2, and implement the standard 《ASTM A370-2024》. The impact absorption work represents the ability of the material to resist damage, which is expressed by the impact absorption work. The larger the value, the stronger the impact resistance of the material.

[0081] Heat-resistant acid and corrosive substance test, implement the standard 《ASTM G28》. According to the standard 《ASTM G28 Method B》, use a mixture of boiling oxidizing salts and sulfuric acid to conduct an intergranular corrosion test, and the corrosion rate < 0.5 mm / year.

[0082] The above test results are shown in Table 1 below.

[0083] Table 1 High-chromium alloy performance test data The hardness, wear resistance, tensile property, impact resistance, and heat-resistant acid and salt corrosion resistance of the high-chromium alloy materials of Examples 1 to 3 are relatively strong.

[0084] Compared with Example 1, Comparative Example 1 has a higher C content and a larger Rockwell hardness, but its tensile property, impact resistance, and heat-resistant acid and salt corrosion resistance decrease. The actual use effect is not as good as that of the high-chromium alloy materials of Examples 1 to 3. Excessive C makes the alloy deformed, hard and brittle, with a decrease in toughness and poor impact resistance.

[0085] Compared with Example 1, the Mn content in Comparative Example 2 is relatively high, and the wear resistance, tensile strength, and impact resistance decrease. Excessive Mn reacts with impurity S to form MnS, which is likely to become the origin of fatigue cracks and reduce the fatigue life of the alloy.

[0086] Compared with Example 1, the Ni content in Comparative Example 3 is relatively low, and the wear resistance, tensile strength, impact resistance, and corrosion resistance to heat-resistant acids and salts decrease.

[0087] Compared with Example 1, the Mo content in Comparative Example 4 is relatively low, and the tensile strength, impact resistance, and corrosion resistance to heat-resistant acids and salts decrease significantly.

[0088] Compared with Example 1, the Cu content in Comparative Example 5 is relatively low, and the impact resistance and corrosion resistance to heat-resistant acids and salts of the material decrease significantly.

[0089] Compared with Example 1, the Gd content in Comparative Example 6 is relatively low, and the corrosion resistance of the material to heat-resistant acids and salts decreases significantly.

[0090] Compared with Example 1, the Ti content in Comparative Example 7 is relatively low, and the hardness, wear resistance, tensile strength, and impact resistance of the material decrease significantly.

[0091] In summary, the present application uses raw materials with the following component ratios: C: 2.8 - 3.0%, Mn: 0.5 - 0.7%, Cr: 26 - 30%, Ni: 2 - 2.5%, Mo: 1.5 - 2.8%, Cu: 0.9 - 1.2%, Gd: 0.05 - 0.10%, Ti: 1 - 3%, with the balance being Fe and inevitable impurities. Through melting and refining, the obtained high-chromium alloy material has good hardness, wear resistance, tensile strength, impact resistance, and corrosion resistance to heat-resistant acids and salts. Applying this high-chromium alloy material to prepare a slurry pump, as Figure 1 shown, the slurry pump includes the following flow-through components: a front guard plate 1, an impeller 2, a volute 3, a rear guard plate 4, and a pump cover 5. This slurry pump can be applied in industries such as mines, power desulfurization, dredging, metallurgy, chemical engineering, building materials, and petroleum. It can resist high-concentration particle erosion, extend the life of key components, adapt to high-temperature acid-salt corrosion media, and maintain the stability of the flow-through structure. In the transportation of acidic high-solid waste slurries, the life of the flow-through components of this slurry pump is greatly improved. In a high-temperature corrosion environment, the maintenance frequency of the flow-through components is greatly reduced. This slurry pump has wide applicability and can meet the usage requirements of various scenarios.

[0092] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high-chromium alloy material, characterized in that, The components include, by mass percentage: C: 2.8 - 3.0%, Mn: 0.5 - 0.7%, Cr: 26 - 30%, Ni: 2 - 2.5%, Mo: 1.5 - 2.8%, Cu: 0.9 - 1.2%, Gd: 0.05 - 0.10%, Ti: 1 - 3%, the balance being Fe and inevitable impurities.

2. The high-chromium alloy material according to claim 1, characterized in that Among the high-chromium alloy materials: the Si content ≤ 0.8%, the P content ≤ 1%, and the S content ≤ 0.06%.

3. A preparation method of a slurry pump, characterized in that, The preparation method includes: S1, Mix the metal raw materials and alloy raw materials according to the component ratio of the high-chromium alloy material in claim 1, melt the metal raw materials and alloy raw materials to obtain a metal liquid; S2, Cast the metal liquid into a mold to obtain a blank, and anneal the blank to obtain the slurry pump.

4. The preparation method of the slurry pump according to claim 3, characterized in that, Step S1 includes: adding a mixed raw material composed of a carbon increasing agent, pure iron, ferromanganese carbon, ferronickel, copper, gadolinium, ferromolybdenum, ferro-titanium, and ferromanganese chromium into a melting furnace, heating and melting to obtain the metal liquid.

5. The preparation method of the slurry pump according to claim 4, wherein, Calculated by mass: the proportion of the carbon increasing agent in the mixed raw material is 0.45 - 0.78%; the proportion of the pure iron in the mixed raw material is 28.92 - 32.6%; the ferromanganese carbon contains 50 - 70% manganese and 2 - 5% carbon, and the proportion of the ferromanganese carbon in the mixed raw material is 1%; the ferronickel contains 20 - 25% nickel, and the proportion of the ferronickel in the mixed raw material is 10%; the proportion of the copper in the mixed raw material is 0.9 - 1.2%; the proportion of the gadolinium in the mixed raw material is 0.05 - 0.10%; the ferromolybdenum contains 50 - 70% molybdenum, and the proportion of the ferromolybdenum in the mixed raw material is 3 - 4%; the ferro-titanium contains 50 - 75% titanium, and the proportion of the ferro-titanium in the mixed raw material is 2 - 4%; the ferromanganese chromium contains 52 - 60% chromium and 4 - 5% carbon, and the proportion of the ferromanganese chromium in the mixed raw material is 50%.

6. The preparation method of the slurry pump according to claim 4 or 5, characterized in that, Step S1 specifically includes: first adding pure iron into the melting furnace, heating to 1540 - 1600 °C to completely melt the pure iron; then adding ferromanganese carbon, ferronickel, copper, and gadolinium into the melting furnace, adding the carbon increasing agent after complete melting, and dispersing the carbon increasing agent evenly; finally adding ferromolybdenum, ferro-titanium, and ferromanganese chromium into the melting furnace, heating to 1860 - 1900 °C to completely melt the raw materials to obtain the metal liquid.

7. The preparation method of the slurry pump according to claim 3, wherein, The annealing in step S2 is: heating the blank cooled to room temperature to 600 - 700 °C and holding for 1 - 2 h, then heating to 900 - 1000 °C and holding for 1 - 2 h, then cooling to 400 - 500 °C and holding for 1 - 2 h, and finally cooling to room temperature.

8. A slurry pump, characterized in that, Prepared by the preparation method of the slurry pump according to any one of claims 3 - 7.

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