High-temperature wear-resistant corrosion-resistant Fe-Cr-W-Si-C alloy material and application

Abstract

The invention discloses a high-temperature wear-resistant corrosion-resistant Fe-Cr-W-Si-C alloy material and application, the high-temperature wear-resistant corrosion-resistant Fe-Cr-W-Si-C alloy material comprises a plurality of structure composition phases, and alloy composition elements comprise Fe, Cr, Si, W and C elements; the W and C elements are added in the form of WC; the alloy comprises the following chemical components in percentage by mass: 39 to 58 weight percent of Fe, 4 to 12 weight percent of Cr, 1.5 to 8 weight percent of Si and 32 to 53.5 weight percent of WC. The alloy material has excellent high-temperature resistance, wear resistance and corrosion resistance, and can be widely applied to a large number of mechanical kinematic pair parts which bear friction and wear effects in the environments of high-temperature oxidation, corrosion and the like in the industries of metallurgy, energy, petroleum, chemical engineering, steel and the like.

Description

Technical Field

[0001] The present application relates to the field of metal material processing, and mainly to a high-temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material and its application. Background Art

[0002] With the development of industrial technology, in industries such as aviation, aerospace, machinery, steel and non-ferrous metal metallurgy, petroleum, chemical industry, electric power and ocean, a large number of moving metal parts are subjected to strong friction and wear under harsh environmental conditions such as corrosion and high temperature. This puts higher requirements on material properties, requiring materials to have excellent wear resistance, corrosion resistance, oxidation resistance and low friction coefficient to ensure long-term stable operation and safety of equipment.

[0003] However, existing metal wear-resistant materials (such as high-speed steel, tool steel, wear-resistant white cast iron, Stellite alloy, etc.) are often not resistant to high temperatures and corrosion, corrosion-resistant materials (such as stainless steel, etc.) are often not resistant to wear and high-temperature oxidation, and oxidation-resistant high-temperature structural materials (such as heat-resistant steel, nickel-based high-temperature alloys, etc.) are often not resistant to wear and corrosion. Therefore, industrial equipment is in urgent need of new alloy materials that have excellent high-temperature resistance, corrosion resistance, wear resistance and low cost. Summary of the invention

[0004] In response to the performance requirements of the existing technology for the application of moving pair metal parts materials under harsh environmental conditions such as corrosion, high temperature and wear, the present application proposes a high-temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material and a high-temperature wear-resistant and erosion-resistant product. This alloy material also has excellent wear resistance (including excellent room temperature and high temperature abrasive wear, adhesive wear, erosion wear, corrosive wear performance, etc.), excellent corrosion resistance, excellent high temperature oxidation resistance and erosion resistance.

[0005] According to the first aspect of the present application, a high-temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material is proposed, whose constituent elements include Fe, Cr, Si, W and C elements; the W and C elements are added in the form of WC; the alloy chemical composition includes Fe: 39-58wt%, Cr: 4-12wt%, Si: 1.5-8wt% and WC: 32-53.5wt% in mass percentage; the alloy includes a structural composition phase a: Fe5Si3 metal silicide solid solution + iron-based solid solution + WC, a structural composition phase b: Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution, a structural composition phase c: Fe5Si3 metal silicide solid solution + Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution and a structural composition phase d: Fe9Cr9Si2 metal silicide solid solution + WC + Cr7C3 + iron-based solid solution. As the main component of the alloy, Fe provides the alloy with basic structure and mechanical strength; Cr improves the corrosion resistance and oxidation resistance of the alloy; Si can further improve the hardness and strength of the alloy, and is also conducive to improving the wear resistance and oxidation resistance of the alloy; WC can bring excellent high temperature resistance, wear resistance and mechanical strength to the alloy. Under the comprehensive effect of each component, the alloy material can have excellent mechanical properties, high temperature resistance, wear resistance and corrosion resistance.

[0006] Furthermore, the composition of the organizational component phase a: Fe5Si3 metal silicide solid solution + iron-based solid solution + WC includes Fe: 52-58wt%, Cr: 4-7wt%, Si: 5-6wt% and WC: 32-38wt% by mass percentage.

[0007] Furthermore, the composition of the organizational component phase b: Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution includes, by mass percentage, Fe: 43-48wt%, Cr: 7-8wt%, Si: 3-6wt% and WC: 42-46wt%.

[0008] Furthermore, the composition of the organizational component phase c: Fe5Si3 metal silicide solid solution + Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution includes, by mass percentage, Fe: 41-48wt%, Cr: 8-10wt%, Si: 6-8wt% and WC: 38-42wt%.

[0009] Furthermore, the composition of the organizational component phase d: Fe9Cr9Si2 metal silicide solid solution + WC + Cr7C3 + iron-based solid solution includes, by mass percentage, Fe: 39-44wt%, Cr: 10-12wt%, Si: 1.5-3wt% and WC: 44-48wt%.

[0010] Furthermore, the alloy may be alloyed by adding 2-7 wt% of Mo. Mo can improve the high temperature oxidation resistance and high temperature wear resistance of the alloy.

[0011] According to the second aspect of the present application, an application of the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material is proposed, and the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material is used to make high temperature wear-resistant and corrosion-resistant mechanical parts and high temperature wear-resistant and corrosion-resistant protective coatings. In addition to the properties of high temperature resistance, wear resistance and corrosion resistance, this alloy material also has good plasticity, and can be smelted into a solid product with metallic properties, and can also be processed into powder, thereby producing a variety of products.

[0012] Furthermore, the preparation method of the high-temperature wear-resistant and erosion-resistant mechanical parts is: an alloy billet is prepared by a method including induction alloy melting or arc alloy melting, and the alloy billet is cast by a water-cooled metal mold casting method to obtain a finished product.

[0013] Furthermore, the preparation method of the high-temperature wear-resistant and erosion-resistant mechanical parts is: alloy powder is prepared by a method including inert gas shielding gas atomization or centrifugal atomization, and the alloy powder is manufactured and formed by a high-energy beam additive manufacturing method such as laser, electron beam, plasma, etc. to obtain a finished product.

[0014] High-temperature wear-resistant and erosion-resistant metal parts can be used for a long time under harsh environmental conditions such as corrosion, high temperature, and strong friction and wear, which can ensure the long-term stable operation and safety of the equipment. According to the specific smelting requirements, cost considerations, environmental standards and other factors in the actual production process, different methods can be selected for the production and casting of high-temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy materials.

[0015] Furthermore, the preparation method of the high-temperature wear-resistant and erosion-resistant protective coating is: alloy powder is obtained by a method including inert gas shielding gas atomization or centrifugal atomization, and the alloy powder is sprayed on the surface of metal mechanical parts by a method including laser cladding, plasma spraying or flame spraying to prepare the high-temperature wear-resistant and erosion-resistant protective coating.

[0016] High-temperature wear-resistant and erosion-resistant protective coatings can provide effective protection for the substrate, improve wear resistance, corrosion resistance and temperature resistance, thereby extending the service life of the substrate and improving product quality and performance.

[0017] Compared with the prior art, this application has the following beneficial effects:

[0018] The high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material of the present application mainly comprises Fe, Cr, Si, W and C, and its main organizational components are Fe5Si3 metal silicide solid solution, Fe9Cr9Si2 metal silicide solid solution, WC and iron-based solid solution. Due to the concentration of the excellent wear resistance (including abrasive wear, adhesive wear, erosion wear and corrosive wear) and corrosion resistance of transition metal silicide and the advantages of high hardness, high temperature resistance and wear resistance of tungsten carbide, the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material involved in the present application has excellent wear resistance (sliding wear, abrasive wear, adhesive wear, erosion and scouring wear, etc.), corrosion resistance (chemical corrosion, thermal corrosion and electrochemical corrosion, etc.) and high temperature oxidation resistance, and is suitable for manufacturing friction and wear motion parts and components working under corrosion, high temperature and other environmental conditions and their surface wear-resistant, corrosion-resistant and high temperature protective coatings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings are included to provide a further understanding of the embodiments and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate the embodiments and are used together with the description to explain the principles of the present invention. It will be easy to recognize other embodiments and many expected advantages of the embodiments because they become better understood by reference to the following detailed description. The elements of the drawings are not necessarily to scale with each other. The same reference numerals refer to corresponding similar parts.

[0020] Figure 1 The 500-fold scanning electron microscope metallographic structure photograph of HTW-1 alloy is shown;

[0021] Figure 2 The 500-fold scanning electron microscope metallographic structure photograph of HTW-2 alloy is shown;

[0022] Figure 3 The 500-fold scanning electron microscope metallographic structure photograph of HTW-3 alloy is shown;

[0023] Figure 4 The 500-fold scanning electron microscope microscopic microstructure of the HTW-4 alloy is shown. DETAILED DESCRIPTION

[0024] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It should also be noted that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings.

[0025] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] Table 1 shows the chemical composition of the alloys in various examples.

[0027] Table 1 Chemical composition of high temperature wear and corrosion resistant Fe-Cr-W-Si-C alloy

[0028]

[0029] Among them, the HTW-1 alloy microstructure consists mainly of Fe5Si3 metal silicide solid solution + WC + iron-based solid solution, the HTW-2 alloy microstructure consists mainly of Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution, the HTW-3 alloy microstructure consists mainly of Fe5Si3 metal silicide solid solution + Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution, and the HTW-4 alloy microstructure consists mainly of Fe9Cr9Si2 metal silicide solid solution + WC + Cr7C3 + iron-based solid solution.

[0030] The following two methods are used to melt and cast the alloy ingots:

[0031] (1) Laser melting method for alloy short ingots: Industrial pure Fe, Cr, Si and cast tungsten carbide powder are used as raw materials, and a water-cooled copper mold laser melting furnace (water-cooled copper mold laser melting furnace and method for melting ingots, Chinese patent CN1180901C, expired) is used to melt a short columnar alloy ingot weighing about 15g. The specific melting and casting steps are: ① Load a mixed alloy powder weighing about 15g into a water-cooled copper mold; ② Turn on cooling water; ③ Turn on protective gas; ④ Introduce a focused laser beam for alloy melting; ⑤ Cool the ingot; ⑥ Turn off the cooling water; ⑦ Turn off the protective gas; ⑧ Take out the ingot from the water-cooled copper mold.

[0032] (2) Large ingot induction melting method: Industrial pure block Fe, Cr and Si, and WC powder are used as raw materials, and the alloy is melted in a 150kg vacuum medium frequency induction melting furnace, and a water-cooled metal mold casting method is used to cast a block casting weighing about 30kg. The specific melting and casting steps are: ① Add Fe and Cr block raw materials and melt them with electricity, and create alkaline slag protection during melting; ② Add Si and WC after melting; ③ After the alloy melt temperature reaches 1580-1660℃, take out of the furnace and pour the ingot; ④ After cooling to room temperature, unpack and take out the casting.

[0033] The cross-section metallographic samples of the alloy ingots were cut respectively, and the Krebs etching reagent (volume ratio of HF:HNO3:H20=1:6:7) was used as the metallographic etching agent, and the microstructure was observed using a JSM-6490 scanning electron microscope. The SEM images of the microstructures of the HTW-1, HTW-2, HTW-3 and HTW-4 alloys are shown in Figure 2. Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, WC, iron-based solid solution, and the main organizational components of each alloy can be clearly seen from each figure.

[0034] The average hardness of the alloy was tested using a MH-6 semi-automatic microhardness tester with a test load of 1 kg. Table 2 shows the hardness of the alloys in various embodiments.

[0035] Table 2 Hardness of high temperature wear and corrosion resistant Fe-Cr-W-Si-C alloy

[0036]

[0037] The cross sections of the alloy ingots were cut respectively, and the room temperature dry sliding wear test was carried out on the MM-200 sliding wear tester. The sample size is 10mm*10mm*10mm, the grinding ring material is quenched + low temperature tempered (hardness HRC53) 45 steel, the normal load is 98N, the grinding ring speed is 400r / min, the wear time is 60min, and the total sliding distance is about 3000m. The quenched + low temperature tempered chromium-molybdenum alloy steel 42CrMo (HRC53) was selected as the standard comparison sample. The wear weight was weighed with a SARTORIUSBS110S electronic balance with an accuracy of 0.1mg, and the "relative wear resistance" (relative wear resistance = standard sample wear loss / sample wear loss) was used as an indicator of the wear resistance of the material. The test results are shown in Table 3.

[0038] Table 3 Comparative test results of high temperature wear and corrosion resistant Fe-Cr-W-Si-C alloy and comparative example 1 at room temperature dry sliding wear

[0039]

[0040] It can be seen from Table 3 that the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy has excellent room temperature wear resistance, which is 52-93 times higher than that of the chromium-molybdenum alloy steel 42CrMo. Among them, the HTW-4 alloy is the best.

[0041] The high temperature sliding wear test was carried out on a HTW-Ⅱ high temperature sliding wear tester. The sample size was a rectangular block of 5mm*5mm*8mm, and the surface of the sample with a size of 5mm*5mm was used as the wear surface. The test temperature was 600℃. 17-4PH stainless steel was selected as the standard comparison sample, and the nickel-based high temperature alloy GH22 (room temperature hardness of about HV500) with high high temperature hardness and excellent oxidation resistance was selected as the disc-shaped grinding pair. The test results are shown in Table 4.

[0042] Table 4 Comparative test results of high temperature dry sliding wear of high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy and comparative example 2

[0043]

[0044]

[0045] It can be seen from Table 4 that the high-temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy also has excellent high-temperature wear resistance, which is 4-16 times higher than that of 17-4PH stainless steel. HTW-4 alloy is also the best.

[0046] The erosion test was conducted on an independently developed erosion test machine. According to the test method specified in ASTM G76, the sample size was 30mm*10mm*6mm, and the 30mm*10mm surface was the test surface. 80-120 mesh corundum particles were used, the particle impact speed was 15-20m / s, the incident angle was 45°, and the coating prepared by surfacing welding on the surface of Q235B steel plate with Kennametal's tungsten carbide / copper (1797379#) welding rod was selected as the standard comparison sample. The test time was 30min, and the test results are shown in Table 5.

[0047] Table 5 Erosion comparison test results of high temperature wear and corrosion resistant Fe-Cr-W-Si-C alloy and comparative example 3

[0048]

[0049] It can be seen from Table 5 that the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy has good erosion resistance. Examples 1-4 are all better than the tungsten carbide / copper cladding layer of Comparative Example 3, which is 5-12 times higher.

[0050] The corrosion test used Kjeldahl corrosion reagent (volume ratio of HF:HNO3:H20=1:6:7) as the corrosion liquid, the sample size was 10mm*10mm*10mm, austenitic stainless steel 304 was selected as the standard comparison sample, and the weight difference of the sample before and after corrosion was weighed with an electronic balance with an accuracy of 0.1mg, that is, the corrosion weight loss. The "relative corrosion resistance" (relative corrosion resistance = standard sample corrosion weight loss / sample corrosion weight loss) was used as an indicator of the alloy's resistance to chemical immersion corrosion. The test results are shown in Table 6.

[0051] Table 6 Comparative test results of chemical immersion corrosion of high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy and comparative example 4

[0052]

[0053] It can be seen from Table 6 that the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy has good corrosion resistance, which is 2-4 times higher than that of austenitic stainless steel 304.

[0054] Example 5

[0055] Laser cladding preparation of high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy coating

[0056] HTW-4 alloy atomized powder with a particle size of 80-150 mesh was selected, and gravity synchronous powder feeding method was used on the IPG type 10kW fiber laser material processing system. Then, laser cladding technology was used to prepare high-temperature Fe-Cr-W-Si-C metal silicide high-temperature wear-resistant and corrosion-resistant alloy coating on Q235B steel. The laser cladding process conditions are: laser output power 4kW, spot size of about 4.5mm and spot scanning speed of 350mm / min. The coating structure is dense and uniform, without cracks and pores, and is completely metallurgically bonded with the low-carbon steel substrate. The coating structure is mainly composed of Fe9Cr9Si2 metal silicide solid solution + WC + Cr7C3 + iron-based solid solution. The coating hardness is evenly distributed, and the average coating hardness is HV1400-1500.

[0057] Example 6

[0058] Additive manufacturing of high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy

[0059] HTW-1 alloy powder with a particle size of 100-300 mesh was selected, and the Fe-Cr-W-Si-C metal silicide alloy complex structure parts were prepared on a 316L stainless steel substrate by selective melting of a high-energy beam (laser beam, electron beam or plasma beam, etc.). The beam spot diameter is 0.1-0.2mm, the average beam input energy is 400-1000W, the beam line scanning speed is 1-5m / s, and the scanning spacing is 0.1-0.3mm. The prepared HTW-1 alloy is composed of Fe5Si3 metal silicide solid solution + WC + iron-based solid solution, with a dense structure without defects and a hardness of up to HV400-450.

[0060] To sum up, the high-temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material provided by the present application has excellent high-temperature resistance, wear resistance and corrosion resistance, and can be widely used in mechanical moving parts that exist in large quantities in industries such as electricity, energy, petroleum, chemical industry, non-ferrous metal metallurgy and steel metallurgy, and are subjected to friction and wear in high-temperature oxidation and corrosion environments. For example: key moving parts of high-temperature and high-pressure valves in industrial equipment such as electricity, chemical industry and metallurgy, mechanical moving parts that are subjected to friction and wear under corrosive conditions in industrial equipment such as chemical industry, petroleum and marine, and high-temperature wear-resistant and corrosion-resistant moving parts in non-ferrous metal and steel metallurgical industries.

[0061] The above describes the specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0062] In the description of the present application, it is to be understood that the word 'comprising' does not exclude the presence of elements or steps not listed in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. A high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material, characterized in that: The alloy components include Fe, Cr, Si, W and C elements; the W and C elements are added in the form of WC; the alloy chemical composition includes Fe: 39-58wt%, Cr: 4-12wt%, Si: 1.5-8wt% and WC: 32-53.5wt% in mass percentage; the alloy includes a structural component phase a: Fe5Si3 metal silicide solid solution + iron-based solid solution + WC, a structural component phase b: Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution, a structural component phase c: Fe5Si3 metal silicide solid solution + Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution and a structural component phase d: Fe9Cr9Si2 metal silicide solid solution + WC + Cr7C3 + iron-based solid solution.

2. The high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 1, characterized in that: The composition of the organizational component phase a: Fe5Si3 metal silicide solid solution+iron-based solid solution+WC includes Fe: 52-58wt%, Cr: 4-7wt%, Si: 5-6wt% and WC: 32-38wt% by mass percentage.

3. The high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 1, characterized in that: The composition of the organizational component phase b: Fe9Cr9Si2 metal silicide solid solution+WC+iron-based solid solution includes, by mass percentage, Fe: 43-48wt%, Cr: 7-8wt%, Si: 3-6wt% and WC: 42-46wt%.

4. The high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 1, characterized in that: The composition of the organizational component phase c: Fe5Si3 metal silicide solid solution + Fe9Cr9Si2 metal silicide solid solution + WC + iron-based solid solution includes Fe: 41-48wt%, Cr: 8-10wt%, Si: 6-8wt% and WC: 38-42wt% by mass percentage.

5. The high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 1, characterized in that: The composition of the organizational component phase d: Fe9Cr9Si2 metal silicide solid solution + WC + Cr7C3 + iron-based solid solution includes, by mass percentage, Fe: 39-44wt%, Cr: 10-12wt%, Si: 1.5-3wt% and WC: 44-48wt%.

6. The high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 1, characterized in that: The alloy may be alloyed by adding 2-7 wt% Mo.

7. An application of a high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material as claimed in any one of claims 1 to 6, characterized in that: The high-temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material is used to manufacture high-temperature wear-resistant and corrosion-resistant mechanical parts and high-temperature wear-resistant and corrosion-resistant protective coatings.

8. The use of the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 7, characterized in that: The method for preparing the high-temperature wear-resistant and erosion-resistant mechanical parts comprises: preparing an alloy blank by a method including induction alloy melting or arc alloy melting, and casting the alloy blank by a water-cooled metal mold casting method to obtain a finished product.

9. The use of the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 7, characterized in that: The preparation method of the high-temperature wear-resistant and erosion-resistant mechanical parts comprises: preparing alloy powder by a method including inert gas shielding gas atomization or centrifugal atomization, and molding the alloy powder by high-energy beam additive manufacturing to obtain a finished product.

10. The use of the high temperature wear-resistant and corrosion-resistant Fe-Cr-W-Si-C alloy material according to claim 7, characterized in that: The preparation method of the high-temperature wear-resistant and erosion-resistant protective coating is as follows: alloy powder is prepared by a method including inert gas shielding gas atomization or centrifugal atomization, and the alloy powder is sprayed on the surface of metal mechanical parts by a method including laser cladding, plasma spraying or flame spraying to prepare the high-temperature wear-resistant and erosion-resistant protective coating.

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