SA182F91 valve body forge piece for fast reactor main steam system and manufacturing method of SA182F91 valve body forge piece

Abstract

The invention provides an SA182F91 valve body forge piece for a fast reactor main steam system, which comprises the following components in percentage by weight: 0.08 to 0.12 percent of C, 0.20 to 0.50 percent of Si, 0.50 to 0.60 percent of Mn, less than or equal to 0.02 percent of P, less than or equal to 0.01 percent of S, 8.00 to 9.50 percent of Cr, 0.85 to 1.05 percent of Mo, 0.20 to 0.25 percent of V, 0.03 to 0.07 percent of N, 0.06 to 0.10 percent of Nb, 0.25 to 0.40 percent of Ni, less than or equal to 0.02 percent of Al, less than or equal to 0.01 percent of Ti, less than or equal to 0.01 percent of Zr, 0.07 to 0.10 percent of Cu, less than or equal to 0.005 percent of Sn, less than or equal to 0.01 percent of As, less than or equal to 0.003 percent of Sb The invention further provides a manufacturing method of the SA182F91 valve body forge piece for the fast reactor main steam system. The SA182F91 valve body forge piece for the fast reactor main steam system, provided by the invention, has relatively good strength, plasticity and toughness.

Description

Technical Field

[0001] The invention belongs to the field of alloy forging, and in particular relates to a SA182 F91 valve body forging for a fast reactor main steam system and a manufacturing method thereof. Background Art

[0002] SA182F91 is a high temperature alloy steel, also known as ASTM A182 Grade F91. SA182F91 has excellent high temperature resistance, can maintain high strength and toughness in high temperature environment, has good thermal stability and oxidation resistance, and can withstand high temperature and high pressure conditions. SA182F91 also has good corrosion resistance, especially for oxidizing media, and performs well under high temperature and high pressure conditions. SA182F91 is widely used in petroleum, petrochemical, chemical, electric power, boiler manufacturing, nuclear power plants, aerospace and other fields, and is often used in high temperature pipelines, high temperature furnaces, grates, burners, valve bodies, petrochemical equipment and other parts and components in high temperature and high pressure environments.

[0003] There are many ways to strengthen metal materials, and most of them will reduce the plasticity and toughness of the materials while increasing their strength. With the continuous advancement of science and technology, the design requirements for alloy steel forgings in the petrochemical and nuclear power industries are getting higher and higher, requiring the materials to have a certain strength while maintaining a certain plasticity and toughness. The existing SA182F91 valve body forgings for the main steam system of fast reactors also face the same problem of balancing strength, plasticity and toughness. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a SA182 F91 valve body forging for a fast reactor main steam system, which has good strength, plasticity and toughness.

[0005] In order to solve the above technical problems, the technical solution of the present invention is:

[0006] A SA182 F91 valve body forging for a fast reactor main steam system, comprising the following components by weight percentage: C 0.08-0.12%, Si 0.20-0.50%, Mn 0.50-0.60%, P≤0.02%, S≤0.01%, Cr 8.00-9.50%, Mo 0.85-1.05%, V 0.20-0.25%, N 0.03-0.07%, Nb 0.06-0.10%, Ni 0.25-0.40%, Al≤0.02%, Ti≤0.01%, Zr≤0.01%, Cu 0.07-0.10%, Sn≤0.005%, As≤0.01%, Sb≤0.003%, Pb≤0.008%, Bi≤0.008%, Ta 0.002-0.004%, the rest is iron.

[0007] Another technical problem to be solved by the present invention is to provide a method for manufacturing the SA182 F91 valve body forging for the main steam system of a fast reactor.

[0008] To solve the above technical problems, the technical solution is:

[0009] A method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system comprises the following steps:

[0010] S1. Electric furnace smelting: prepare raw materials, place the raw materials in an electric furnace, and smelt until the temperature reaches 1560-1600°C to obtain molten steel;

[0011] S2. Refining outside the furnace: The molten steel obtained in step S1 is placed in a LF furnace, refined to a temperature of 1550-1590 ° C, and then vacuum degassed for 15-20min, and then cast into an ingot;

[0012] S3 forging: The steel ingot obtained in step S2 is subjected to upsetting and drawing by a press to obtain a forging;

[0013] S4. Heat treatment: normalizing the forging obtained in step S3, and then quenching and tempering to obtain SA182 F91 valve body forgings for the main steam system of a fast reactor;

[0014] S5. Testing: Perform physical and chemical testing and nondestructive testing on the SA182 F91 valve body forgings for the fast reactor main steam system obtained in step S4.

[0015] Furthermore, in step S3 of the present invention, the total forging ratio is ≥5.5.

[0016] Furthermore, in step S3 of the present invention, the initial forging temperature is 1180-1220°C, and the final forging temperature is 800-850°C.

[0017] Furthermore, in step S3 of the present invention, the removal ratio of the ingot head is ≥10%, and the removal ratio of the ingot tail is ≥5%.

[0018] Furthermore, in step S4 of the present invention, the heat treatment is carried out in an industrial resistance furnace.

[0019] Furthermore, in step S4 of the present invention, the normalizing temperature is 1060-1080°C.

[0020] Furthermore, in step S4 of the present invention, the quenching temperature is 1050-1070°C.

[0021] Furthermore, in step S4 of the present invention, the tempering temperature is 750-770° C., and the tempering cooling method is water cooling.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1) Refining the grains of metal materials can improve the strength of metal materials while increasing plasticity and toughness, thereby improving the comprehensive performance of metal materials. It is an ideal strengthening method. Therefore, the present invention increases the content of the refining element V, which can effectively refine the grains. A small amount of Ta is also added to the raw materials, which is also conducive to grain refinement.

[0024] 2) The present invention utilizes a combination of upsetting and drawing processes in the forging process to fully forge the forging, reasonably distribute the deformation amount, and further refine the grains of the forging by utilizing the material recrystallization effect during the forging process.

[0025] 3) The present invention adds a normalizing treatment before the quenching and tempering heat treatment, fully utilizes the phase change during the heat treatment process to refine the grains, and controls the heat treatment temperature and holding time to prevent the grains from growing.

[0026] 4) The present invention increases the content of Ni element, which can effectively improve the impact toughness of the forging, and also increases the content of Mn element, which can effectively improve the hardenability of the forging. DETAILED DESCRIPTION

[0027] The present invention will be described in detail below in conjunction with specific embodiments. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention but are not intended to limit the present invention.

[0028] Example 1

[0029] SA182 F91 valve body forgings for the main steam system of fast reactors are composed of the following components, measured by weight percentage: C 0.09%, Si 0.40%, Mn 0.55%, P 0.02%, S 0.01%, Cr 8.50%, Mo 0.95%, V 0.22%, N 0.05%, Nb 0.08%, Ni 0.35%, Al 0.01%, Ti 0.01%, Zr 0.009%, Cu 0.08%, Sn 0.005%, As 0.009%, Sb 0.003%, Pb 0.007%, Bi 0.008%, Ta 0.003%, and the rest is iron.

[0030] The manufacturing method of embodiment 1 comprises the following steps:

[0031] S1. Electric furnace smelting: prepare raw materials, place the raw materials in an electric furnace, and smelt until the temperature reaches 1580°C to obtain molten steel;

[0032] S2 refining outside the furnace: the molten steel obtained in step S1 is placed in a LF furnace, refined to a temperature of 1570 ° C, vacuum degassing treatment for 18min, and then cast into an ingot;

[0033] S3. Forging: The steel ingot obtained in step S2 is subjected to upsetting and drawing by a press to obtain a forging, the total forging ratio is 5.7, the initial forging temperature is 1200°C, the final forging temperature is 830°C, the removal ratio of the ingot head is 10%, and the removal ratio of the ingot tail is 5%;

[0034] S4. Heat treatment: The forging obtained in step S3 is normalized in an industrial resistance furnace, and then quenched and tempered to obtain SA182 F91 valve body forgings for the main steam system of a fast reactor, the normalizing temperature is 1070°C, the quenching temperature is 1060°C, the tempering temperature is 760°C, and the tempering cooling method is water cooling;

[0035] S5. Testing: Perform physical and chemical testing and nondestructive testing on the SA182 F91 valve body forgings for the fast reactor main steam system obtained in step S4.

[0036] Example 2

[0037] SA182 F91 valve body forgings for the main steam system of fast reactors are composed of the following components, measured by weight percentage: C 0.10%, Si 0.30%, Mn 0.58%, P 0.01%, S 0.008%, Cr 8.30%, Mo 1.05%, V 0.20%, N 0.07%, Nb 0.09%, Ni 0.40%, Al 0.02%, Ti 0.01%, Zr 0.008%, Cu 0.09%, Sn 0.004%, As 0.01%, Sb 0.002%, Pb 0.007%, Bi 0.008%, Ta 0.002%, and the rest is iron.

[0038] The manufacturing method of embodiment 2 comprises the following steps:

[0039] S1. Electric furnace smelting: prepare raw materials, place the raw materials in an electric furnace, and smelt until the temperature reaches 1590°C to obtain molten steel;

[0040] S2 refining outside the furnace: the molten steel obtained in step S1 is placed in a LF furnace, refined to a temperature of 1580 ° C, vacuum degassing treatment for 16min, and then cast into an ingot;

[0041] S3. Forging: The steel ingot obtained in step S2 is subjected to upsetting and drawing by a press to obtain a forging, the total forging ratio is 5.5, the initial forging temperature is 1210°C, the final forging temperature is 840°C, the removal ratio of the ingot head is 11%, and the removal ratio of the ingot tail is 5%;

[0042] S4. Heat treatment: The forging obtained in step S3 is normalized in an industrial resistance furnace, and then quenched and tempered to obtain SA182 F91 valve body forgings for the main steam system of a fast reactor, the normalizing temperature is 1080°C, the quenching temperature is 1070°C, the tempering temperature is 750°C, and the tempering cooling method is water cooling;

[0043] S5. Testing: Perform physical and chemical testing and nondestructive testing on the SA182 F91 valve body forgings for the fast reactor main steam system obtained in step S4.

[0044] Example 3

[0045] SA182 F91 valve body forgings for the main steam system of fast reactors are composed of the following components, measured by weight percentage: C 0.08%, Si 0.20%, Mn 0.60%, P 0.01%, S 0.009%, Cr 8.00%, Mo 0.85%, V 0.24%, N 0.06%, Nb 0.06%, Ni 0.25%, Al 0.02%, Ti 0.009%, Zr 0.01%, Cu 0.10%, Sn 0.004%, As 0.009%, Sb 0.003%, Pb 0.008%, Bi 0.007%, Ta 0.004%, and the rest is iron.

[0046] The manufacturing method of embodiment 3 comprises the following steps:

[0047] S1. Electric furnace smelting: prepare raw materials, place the raw materials in an electric furnace, and smelt until the temperature reaches 1560°C to obtain molten steel;

[0048] S2 refining outside the furnace: the molten steel obtained in step S1 is placed in a LF furnace, refined to a temperature of 1550 ℃, vacuum degassing treatment for 20min, and then cast into an ingot;

[0049] S3. Forging: The steel ingot obtained in step S2 is subjected to upsetting and drawing by a press to obtain a forging, the total forging ratio is 5.6, the initial forging temperature is 1180°C, the final forging temperature is 800°C, the removal ratio of the ingot head is 10%, and the removal ratio of the ingot tail is 6%;

[0050] S4. Heat treatment: The forging obtained in step S3 is normalized in an industrial resistance furnace, and then quenched and tempered to obtain SA182 F91 valve body forgings for the main steam system of a fast reactor, the normalizing temperature is 1060°C, the quenching temperature is 1050°C, the tempering temperature is 750°C, and the tempering cooling method is water cooling;

[0051] S5. Testing: Perform physical and chemical testing and nondestructive testing on the SA182 F91 valve body forgings for the fast reactor main steam system obtained in step S4.

[0052] Example 4

[0053] SA182 F91 valve body forgings for the main steam system of fast reactors are composed of the following components, measured by weight percentage: C 0.12%, Si 0.50%, Mn 0.50%, P 0.02%, S 0.01%, Cr 9.50%, Mo 0.90%, V 0.25%, N 0.03%, Nb 0.10%, Ni 0.30%, Al 0.01%, Ti 0.008%, Zr 0.010%, Cu 0.07%, Sn 0.005%, As 0.010%, Sb 0.002%, Pb 0.008%, Bi 0.007%, Ta 0.003%, and the rest is iron.

[0054] The manufacturing method of embodiment 4 comprises the following steps:

[0055] S1. Electric furnace smelting: prepare raw materials, place the raw materials in an electric furnace, and smelt until the temperature reaches 1600°C to obtain molten steel;

[0056] S2 refining outside the furnace: the molten steel obtained in step S1 is placed in a LF furnace, refined to a temperature of 1590 ° C, vacuum degassing treatment for 15min, and then cast into an ingot;

[0057] S3. Forging: The steel ingot obtained in step S2 is subjected to upsetting and drawing by a press to obtain a forging, the total forging ratio is 5.5, the initial forging temperature is 1220°C, the final forging temperature is 850°C, the removal ratio of the ingot head is 11%, and the removal ratio of the ingot tail is 6%;

[0058] S4. Heat treatment: The forging obtained in step S3 is normalized in an industrial resistance furnace, and then quenched and tempered to obtain SA182 F91 valve body forgings for the main steam system of a fast reactor, the normalizing temperature is 1070°C, the quenching temperature is 1060°C, the tempering temperature is 770°C, and the tempering cooling method is water cooling;

[0059] S5. Testing: Perform physical and chemical testing and nondestructive testing on the SA182 F91 valve body forgings for the fast reactor main steam system obtained in step S4.

[0060] Comparative Example 1

[0061] The composition of the forging is: C 0.09%, Si 0.40%, Mn 0.55%, P 0.02%, S 0.01%, Cr8.50%, Mo 0.95%, V 0.19%, N 0.05%, Nb 0.08%, Ni 0.35%, Al 0.01%, Ti 0.01%, Zr0.009%, Cu 0.08%, Sn 0.005%, As 0.009%, Sb 0.003%, Pb 0.007%, Bi 0.008%, Ta0.003%, and the rest is iron; its manufacturing method is the same as that of Example 1. The difference from Example 1 is that the content of V element in Comparative Example 1 is lower than the range defined by the present invention.

[0062] Comparative Example 2

[0063] The composition of the forging is: C 0.09%, Si 0.40%, Mn 0.55%, P 0.02%, S 0.01%, Cr8.50%, Mo 0.95%, V 0.22%, N 0.05%, Nb 0.08%, Ni 0.35%, Al 0.01%, Ti 0.01%, Zr0.009%, Cu 0.08%, Sn 0.005%, As 0.009%, Sb 0.003%, Pb 0.007%, Bi 0.008%, and the rest is iron; its manufacturing method is the same as that of Example 1. The difference from Example 1 is that the composition of Comparative Example 2 does not contain Ta element.

[0064] Comparative Example 3

[0065] The composition of the forging is: C 0.09%, Si 0.40%, Mn 0.55%, P 0.02%, S 0.01%, Cr8.50%, Mo 0.95%, V 0.22%, N 0.05%, Nb 0.08%, Ni 0.24%, Al 0.01%, Ti 0.01%, Zr0.009%, Cu 0.08%, Sn 0.005%, As 0.009%, Sb 0.003%, Pb 0.007%, Bi 0.008%, Ta0.003%, and the rest is iron; its manufacturing method is the same as that of Example 1. The difference from Example 1 is that the content of Ni element in Comparative Example 3 is lower than the range defined by the present invention.

[0066] Comparative Example 4

[0067] The composition of the forging is: C 0.09%, Si 0.40%, Mn 0.49%, P 0.02%, S 0.01%, Cr8.50%, Mo 0.95%, V 0.22%, N 0.05%, Nb 0.08%, Ni 0.35%, Al 0.01%, Ti 0.01%, Zr0.009%, Cu 0.08%, Sn 0.005%, As 0.009%, Sb 0.003%, Pb 0.007%, Bi 0.008%, Ta0.003%, and the rest is iron; its manufacturing method is the same as that of Example 1. The difference from Example 1 is that the content of the Mn element in Comparative Example 4 is lower than the range defined by the present invention.

[0068] Comparative Example 5

[0069] The composition of the forging is the same as that of Example 1. The difference from Example 1 is that step S4 does not include a normalizing operation.

[0070] Experimental Example 1: Grain Test

[0071] The forgings prepared in Examples 1-4, Comparative Examples 1-2, and Comparative Example 5 were respectively tested for average grain diameter according to GB / T 6394-2017 “Method for Determination of Average Grain Size of Metals”, and the test results are shown in Table 1.

[0072] Average grain diameter (μm) Example 1 102.7 Example 2 104.3 Example 3 102.4 Example 4 103.6 Comparative Example 1 151.5 Comparative Example 2 144.8 Comparative Example 5 152.9

[0073] Table 1

[0074] As can be seen from Table 1, the average grain diameters of Examples 1-4 are all small, indicating that the SA182 F91 valve body forgings for the main steam system of a fast reactor prepared by the present invention have a higher grain size. Compared with Example 1, the average grain sizes of Comparative Examples 1, 2, and 5 are all increased, indicating that the operations of increasing the V element content, adding Ta elements to the composition, and adding a normalizing treatment before quenching and tempering adopted by the present invention can effectively refine the grains.

[0075] Experimental Example 2: Impact Test

[0076] The SA182 F91 valve body forgings for the main steam system of the fast reactor prepared in Examples 1-4 and Comparative Example 3 were respectively subjected to impact tests. The impact tests were performed with reference to the standard test method for mechanical properties test of steel products in ASTM A370-2015 (3 specimens, taking the average value). The test results are shown in Table 2.

[0077]

[0078] Table 2

[0079] As can be seen from Table 2, the absorbed energy and lateral expansion values ​​of Examples 1-4 are relatively high, indicating that the SA182 F91 valve body forging for the main steam system of a fast reactor prepared by the present invention has good toughness. Compared with Example 1, the absorbed energy and lateral expansion values ​​of Comparative Example 3 are both reduced, indicating that the operation of increasing the Ni element content adopted by the present invention can effectively improve the toughness of the valve body forging.

[0080] Experimental Example 3: Hardenability Test

[0081] The SA182 F91 valve body forgings for the main steam system of the fast reactor prepared in Examples 1-4 and Comparative Example 4 were subjected to hardenability tests respectively. The hardenability tests were conducted with reference to the end quenching test method for hardenability of steel in GB / T 225-2006. The test results are shown in Table 3.

[0082] Hardness at 19mm from the water cooling end (HRC) Example 1 32 Example 2 31 Example 3 33 Example 4 31 Comparative Example 4 28

[0083] Table 3

[0084] As can be seen from Table 3, the hardness of Examples 1-4 at 19 mm from the water-cooled end is relatively high, indicating that the SA182 F91 valve body forging for the main steam system of a fast reactor prepared by the present invention has good hardenability. Compared with Example 1, the hardness of Comparative Example 4 at 19 mm from the water-cooled end is reduced, indicating that the operation of increasing the Mn element content adopted by the present invention can effectively improve the hardenability of the valve body forging.

[0085] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A SA182 F91 valve body forging for a fast reactor main steam system, characterized in that: In terms of weight percentage, it is composed of the following components: C 0.08-0.12%, Si 0.20-0.50%, Mn 0.50-0.60%, P≤0.02%, S≤0.01%, Cr8.00-9.50%, Mo 0.85-1.05%, V 0.20-0.25%, N 0.03-0.07%, Nb 0.06-0.10%, Ni0.25-0.40%, Al≤0.02%, Ti≤0.01%, Zr≤0.01%, Cu 0.07-0.10%, Sn≤0.005%, As≤0.01%, Sb≤0.003%, Pb≤0.008%, Bi≤0.008%, Ta 0.002-0.004%, and the rest is iron.

2. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 1, characterized in that: The following steps are involved: S1. Electric furnace smelting: prepare raw materials, place the raw materials in an electric furnace, and smelt until the temperature reaches 1560-1600°C to obtain molten steel; S2. Refining outside the furnace: The molten steel obtained in step S1 is placed in a LF furnace, refined to a temperature of 1550-1590 ° C, and then vacuum degassed for 15-20min, and then cast into an ingot; S3 forging: The steel ingot obtained in step S2 is subjected to upsetting and drawing by a press to obtain a forging; S4 heat treatment: the forging obtained in step S3 is normalized, and then quenched and tempered to obtain a SA182F91 valve body forging for the main steam system of a fast reactor; S5. Testing: Perform physical and chemical testing and nondestructive testing on the SA182 F91 valve body forgings for the fast reactor main steam system obtained in step S4.

3. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 2, characterized in that: In the step S3, the total forging ratio is ≥5.

5.

4. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 2, characterized in that: In step S3, the initial forging temperature is 1180-1220°C, and the final forging temperature is 800-850°C.

5. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 2, characterized in that: In the step S3, the removal ratio of the ingot head is ≥10%, and the removal ratio of the ingot tail is ≥5%.

6. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 2, characterized in that: In step S4, the heat treatment is performed in an industrial resistance furnace.

7. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 2, characterized in that: In step S4, the normalizing temperature is 1060-1080°C.

8. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 2, characterized in that: In step S4, the quenching temperature is 1050-1070°C.

9. The method for manufacturing a SA182 F91 valve body forging for a fast reactor main steam system according to claim 2, characterized in that: In step S4, the tempering temperature is 750-770° C., and the tempering cooling method is water cooling.

Images