Nickel-based superalloy bar reinforced by nano ceramic particles and preparation method of nickel-based superalloy bar

Abstract

The invention provides a nano ceramic particle reinforced nickel-based superalloy bar and a preparation method thereof, and relates to the technical field of superalloy.The preparation method comprises the steps that Al powder, Ti powder and B4C powder are subjected to ball milling according to a certain proportion to obtain mixed powder, and an intermediate alloy containing nano ceramic particles is prepared through a combustion synthesis method; and then the intermediate alloy is added in the smelting process of the nickel-based superalloy, hot working and solid solution aging treatment are carried out, and the nano ceramic particle reinforced nickel-based superalloy bar is successfully prepared. According to the nano ceramic particle reinforced nickel-based high-temperature alloy bar and the preparation method thereof, the hardness, the high-temperature yield strength and the tensile strength of the prepared nickel-based high-temperature alloy bar are obviously improved; the surface pollution of the nano ceramic particles is avoided, the nano ceramic particles can be uniformly dispersed in a matrix, the dispersion strengthening effect is promoted, meanwhile, the original smelting process is reserved, and the material preparation cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high-temperature alloys, in particular to a kind of nano ceramic particle reinforced nickel-based high-temperature alloy rod and preparation method thereof. BACKGROUND

[0002] Nickel-based high-temperature alloy can maintain high strength and good oxidation resistance and corrosion resistance in the range of 650-1000 ℃, which can meet the long-term work of the hot end components of the aero-engine at high temperature. The traditional nickel-based high-temperature alloy mainly improves the performance through solid solution strengthening, precipitation strengthening and grain boundary strengthening. However, when the service temperature approaches or exceeds the dissolution temperature of the alloy strengthening phase, significant coarsening or even dissolution occurs, resulting in a sharp decrease in high-temperature strength and creep resistance of the alloy. In addition, under the action of long-term high temperature stress, grain boundary migration and void nucleation and growth become the main creep failure mechanism, and the effect of traditional strengthening methods in inhibiting grain boundary migration gradually weakens.

[0003] In order to further improve the comprehensive mechanical properties of traditional nickel-based high-temperature alloy, introducing ceramic particles as reinforcing phase is considered as one of the effective ways to break through the bottleneck of high-temperature performance of nickel-based alloy; hard ceramic particles with good compatibility with metal matrix have high melting point, high hardness and excellent room temperature and high temperature stability, which can effectively hinder dislocation movement and grain boundary migration, and improve the strength and creep resistance of the alloy. However, there are significant limitations in traditional micron-sized ceramic particle reinforced nickel-based alloy: first, micron-sized ceramic particles have large size, which can easily cause stress concentration and crack initiation. Second, the interface area with the metal matrix is relatively small, and the interface bonding strength has a great influence on the overall performance. In addition, ceramic phase is easy to agglomerate, which can cause problems such as uneven microstructure and abnormal grain growth of the matrix. The above limitations can reduce the mechanical properties of nickel-based high-temperature alloy. SUMMARY

[0004] The purpose of the present application is to overcome the deficiencies in the prior art, and to provide a kind of nano ceramic particle reinforced nickel-based high-temperature alloy rod and preparation method thereof, which can make nano ceramic particles uniformly distributed in the matrix alloy, and the high-temperature strength and hardness of the obtained rod are significantly improved.

[0005] The technical solution adopted by the present application is: The application discloses a kind of nanoceramic particle reinforced nickel-based superalloy rod, wherein, nickel-based superalloy rod includes the following components by mass percentage: C: 0.015%~0.06%, Cr: 17%~21%, Mo: 2.8%~3.3%, Nb: 5.0%~5.5%, Ti: 0.75%~1.15%, Al: 0.3%~0.7%, Ni: 50%~55%, B≤0.006%, Co≤1.0%, Mn≤0.35%, Si≤0.35%, S≤0.002%, P≤0.005%, Mg≤0.005%, the rest is Fe, and the total is 100%.

[0006] A kind of nanoceramic particle reinforced nickel-based superalloy rod preparation method, wherein: including the following steps: Step S1. Al powder, Ti powder and B4C powder are mixed, and then ball milling treatment is carried out to obtain mixed powder; Step S2. The mixed powder is pressed into a compact, pure aluminum is placed in a medium frequency furnace, and the medium frequency furnace is heated to 800~850℃, argon gas is covered to cover the melt, then the compact is immersed into the bottom of the melt after reaction, after the reaction is completed, the melt temperature is controlled at 800~850℃, and stirring, finally, after cooling to room temperature, the intermediate alloy is taken out and crushed into granular shape; Step S3. The metal Ni, Cr, Fe, Mo, Nb, Co, graphite C raw materials are weighed according to the content of each component of the nickel-based superalloy rod, and the above raw materials are put into a vacuum induction furnace and vacuum is started, the temperature of the molten pool is maintained at 1550~1650℃, the alloy is slowly melted and electromagnetic stirring is carried out; After the alloy is melted, the weighed metal Al, Ti raw material and intermediate alloy are added, the temperature of the molten pool is maintained at 1500~1550℃ and electromagnetic stirring is carried out; The smelted alloy is poured under the protection of argon, and the electrode rod is obtained after cooling; Step S4. The electrode rod prepared in step S3 is subjected to electroslag remelting to form an ingot, and then the ingot is cooled for 2~3h and demoulded, and air-cooled; Step S5. The ingot prepared in step S4 is subjected to high-temperature homogenization diffusion annealing, and then air-cooled; Step S6. The ingot after homogenization diffusion annealing in step S5 is subjected to circumferential surface rolling and pre-heating through a heating furnace, and is subjected to multi-pass upsetting and drawing to the forged size to obtain a forged blank; Step S7. The forged blank prepared in step S6 is turned to be free of cracks on the surface, and then is subjected to solid solution treatment and aging treatment in sequence, and is taken out and air-cooled to obtain the nanoceramic particle reinforced nickel-based superalloy rod.

[0007] Preferably, the preparation method of the nanoceramic particle reinforced nickel-based superalloy rod, wherein: the rotation speed of the ball milling in step S1 is 60-100 r / min, the ball milling time is 15-25 h, and the molar ratio of the Al powder, the Ti powder and the B4C powder in the mixed powder is 4-4.5:2.5-3:1; the particle size of the Ti powder is 20-40 μm, the particle size of the B4C powder is 5-15 μm, and the particle size of the Al powder is 20-30 μm.

[0008] Preferably, the preparation method of the nanoceramic particle reinforced nickel-based superalloy rod, wherein: the stirring time in step S2 is 20-30 min, and the particle diameter of the intermediate alloy is ≤1 mm.

[0009] Preferably, the preparation method of the nanoceramic particle reinforced nickel-based superalloy rod, wherein: the mass ratio of the intermediate alloy to the total weight of the raw materials in step S3 is 0.1%-0.2%:1, and the pouring temperature is 1450-1480℃.

[0010] Preferably, the preparation method of the nanoceramic particle reinforced nickel-based superalloy rod, wherein: the temperature of the molten slag added during the electroslag remelting in step S4 is 1260-1320℃, the working current is 2800-3200 A, the working voltage is 45-50 V, and the molten slag comprises 70% CaF2, 15% CaO and 15% Al2O3.

[0011] Preferably, the preparation method of the nanoceramic particle reinforced nickel-based superalloy rod, wherein: the high-temperature homogenization diffusion annealing in step S5 specifically comprises the following steps: slowly heating the cast ingot from room temperature to 1160-1180℃, maintaining for 30-40 h, directly heating to 1200-1220℃ after the end, maintaining for 30-40 h, and then taking out and air cooling.

[0012] Preferably, the preparation method of the nanoceramic particle reinforced nickel-based superalloy rod, wherein: each pass of the upsetting and drawing in step S6 comprises the steps of heating, upsetting, heating and drawing, the average deformation amount of each pass of the upsetting is controlled to be 40%-50% during the upsetting and drawing, the heating temperature of each pass of the drawing is controlled to be 1130-1150℃, and the holding time is 2-4 h; during the drawing, the heating temperature of the first pass of the drawing is controlled to be 1130-1150℃, the heating temperature of the second pass of the drawing is controlled to be 1110-1130℃, the deformation amount is controlled to be 40%-50%, and the holding time is 2-4 h; the last pass is subjected to the deformation and rounding steps, the heating temperature is controlled to be 1110-1130℃, the deformation amount is controlled to be 20%-30%, and the holding time is 2-4 h; and the cross-sectional size of the alloy ingot after the forging is Φ300-320 mm.

[0013] Preferably, the method for preparing the nano-ceramic particle reinforced nickel-based superalloy rod, wherein the temperature of the solution treatment in step S7 is 950-980℃, and the holding time is 120-140min.

[0014] Preferably, the method for preparing the nano-ceramic particle reinforced nickel-based superalloy rod, wherein the aging treatment in step S7 is specifically as follows: the solution-treated forged blank is heated to 680-720℃, and held for 8-10h, then cooled to 600-620℃ at a rate of 50-55℃ / h, and held for 8-10h, and then air-cooled.

[0015] Advantages of the present application: (1) The nano-ceramic particles are introduced into the melting process of the superalloy in the form of an intermediate alloy, which not only avoids the surface contamination of the nano-ceramic particles, makes them uniformly dispersed in the matrix, and promotes the dispersion strengthening effect, but also retains the original smelting process, and reduces the material preparation cost.

[0016] (2) After the nano-ceramic particle reinforced superalloy is subjected to heat treatment and solution aging treatment, the average grain size is 20-40μm, which is obviously finer than that of the collective alloy without the nano-ceramic particles. The added nano-ceramic particles play a role of heterogeneous nucleation in the superalloy matrix, increase the number of nucleation, and achieve the effect of fine-grain strengthening. In addition, the hardness, high-temperature yield and tensile strength are also significantly improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The grain size diagram of the nano-ceramic particle reinforced nickel-based superalloy rod prepared for Example 1 of the present application.

[0018] Figure 2 The grain size diagram of the nano-ceramic particle reinforced nickel-based superalloy rod prepared for Example 2 of the present application.

[0019] Figure 3 The grain size diagram of the nano-ceramic particle reinforced nickel-based superalloy rod prepared for Example 3 of the present application. DETAILED DESCRIPTION

[0020] The present application will be further described below in conjunction with specific examples.

[0021] Example 1 A nano-ceramic particle reinforced nickel-based superalloy rod 1, and the preparation method thereof comprises the following steps: Step S1. Al powder, Ti powder and B4C powder are mixed and placed in a ball mill jar, and mechanical ball milling is carried out at a rotating speed of 80 r / min for 20 h to uniformly mix, wherein the molar ratio of Al powder, Ti powder and B4C powder in the mixed powder is 4:3:1, the particle size range of Ti powder is 20-40 μm, the particle size range of B4C powder is 5-15 μm, and the particle size range of Al powder is 20-30 μm; ethanol solution is added to the mixed powder after ball milling, ultrasonic oscillation treatment is carried out for 4 h, and then the mixed powder is placed in a drying box and dried for 4 h to obtain a mixed powder; Step S2. The mixed powder is placed in a vacuum press, and the pressure is maintained at 30 MPa for 15 min, then the pressure is increased to 120 MPa at a rate of 15 MPa / min, and the pressure is maintained for 30 min to press a block; pure aluminum is placed in a medium-frequency furnace, the frequency is 12 kHz, the temperature is raised to 850℃, and the melt is covered with argon gas; the block is placed in a preheated graphite bell, immersed in the bottom of the melt by a pneumatic device, the tungsten electrode ignition system is started, and the self-propagating reaction is triggered; after the reaction is completed, the melt temperature is adjusted back to 850℃, a high-speed stirrer is inserted and strongly stirred for 30 min; a high-pressure water cooling system is started, and after cooling to room temperature, the intermediate alloy is taken out and crushed into granules with a particle diameter of not more than 1 mm; Step S3. The raw materials of metal Ni, Cr, Fe, Mo, Nb, Co and graphite C are weighed according to the formula, and the above raw materials are placed in a vacuum induction furnace and vacuum is started to be drawn. When the vacuum degree reaches 10 Pa, the power of the vacuum induction furnace is adjusted to 20 kW to heat for 20 min. Continue to draw vacuum, and when the vacuum degree is less than 5 Pa, adjust the power of the vacuum induction furnace to 50 kW, keep the temperature of the molten pool within 1600℃, slowly melt the alloy and conduct electromagnetic stirring. After the alloy is melted, the weighed metal Al, Ti raw materials and the intermediate alloy powder prepared in step S2 are added, wherein the mass ratio of the total weight of the added intermediate alloy and raw materials is 0.1%:1. The power of the vacuum induction furnace is reduced to 35 kW, the temperature of the molten pool is kept at 1520℃ for 30 min for refining, and electromagnetic stirring is conducted for 2 h to further reduce the content of gaseous elements in the molten pool. The smelted alloy is poured under the protection of argon gas, and the pouring temperature is 1480℃. After cooling, an electrode rod is obtained; Step S4. The electrode rod prepared in step S3 is subjected to electroslag remelting, the bottom of the electrode rod is welded to a dummy electrode and placed in an electroslag remelting furnace, melted by the resistance heat generated when the current passes through the molten slag, the metal droplets pass through the slag layer to reduce the content of various non-metallic impurities, and the ingot is formed by solidification and crystallization in the crystallizer. After cooling for 3 h, demoulding and air cooling are carried out. The temperature of the molten slag added during electroslag remelting is 1300℃, the working current is 3000 A, the working voltage is 50 V, and the molten slag includes 70% CaF2, 15% CaO and 15% Al2O3.

[0022] Step S5. The ingot obtained in step S4 is subjected to high-temperature homogenization diffusion annealing to promote the dissolution of the primary phase and eliminate the segregation of alloying elements. The ingot is slowly heated from room temperature to 1160°C and held for 36 hours. After the heating is completed, the temperature is directly raised to 1200°C and held for another 36 hours. Then it is taken out and air-cooled. Step S6. The ingot obtained in step S5 is circumferentially rolled and preheated in a heating furnace. The billet is obtained by three upsetting and three drawing processes to the desired forging size. Each upsetting and drawing process includes heating, upsetting, heating and drawing. During the upsetting and drawing process, the average deformation of each upsetting process is controlled at 42%, the heating temperature of each process is controlled at 1140℃, and the holding time is 4h. During the drawing process, the heating temperature is controlled at 1140℃ for the first drawing process and at 1130℃ for the second drawing process. The deformation is controlled at 44%, and the holding time is 4h. The last process is to perform deformation and rounding, with the heating temperature controlled at 1120℃, the deformation controlled at 24%, and the holding time being 4h.

[0023] Step S7. After the forging billet obtained in step S6 is machined to the point where there are no cracks on the surface, it is subjected to solution aging treatment. The solution treatment temperature is 980℃, and it is held for 2 hours. Then it is taken out and water-cooled. The aging treatment temperature is 720℃. The bar is placed in a resistance furnace and held for 10 hours. Then it is cooled to 620℃ with the furnace at 50℃ / h. Then it is held for 8 hours. Then it is taken out and air-cooled.

[0024] The microstructure of the nickel-based superalloy rod 1 reinforced with nano-ceramic particles prepared in this embodiment is as follows: Figure 1 As shown, from Figure 1 It can be seen that the microstructure is equiaxed crystals with an average grain size of 40~50μm. The yield strength, tensile strength and elongation are 1056MPa, 1124MPa and 23.5%, respectively, and the room temperature hardness is 419HV.

[0025] Example 2 A nickel-based superalloy rod reinforced with nano-ceramic particles 2 is prepared by the following steps: Step S1. Al powder, Ti powder, and B4C powder are mixed and placed in a ball mill jar. The mixture is mechanically ball-milled at 80 r / min for 20 h to ensure uniform mixing. The molar ratio of Al powder, Ti powder, and B4C powder in the mixed powder is 4:3:1. The particle size range of Ti powder is 20–40 μm, the particle size range of B4C powder is 5–15 μm, and the particle size range of Al powder is 20–30 μm. After ball milling, an ethanol solution is added to the mixed powder, and the mixture is subjected to ultrasonic vibration for 4 h. Finally, it is dried in a drying oven for 4 h to obtain the mixed powder. Step S2. The mixed powder is placed in a vacuum press, and is pressed at a pressure of 30 MPa for 15 min, and then is pressed at a rate of 15 MPa / min to 120 MPa, and is pressed for 30 min to form a compact; the pure aluminum is placed in a medium-frequency furnace, and is heated to 850 DEG C at a frequency of 12 kHz, and is covered with argon gas; the compact is placed in a preheated graphite bell, and is immersed into the bottom of the melt by a pneumatic device, and a tungsten electrode ignition system is started, and a self-propagating reaction is triggered; after the reaction is completed, the temperature of the melt is adjusted back to 850 DEG C, and a high-speed stirrer is inserted to stir the melt for 30 min; a high-pressure water cooling system is started, and after being cooled to room temperature, the intermediate alloy is taken out and is crushed into a granular form, and the diameter of the granules is not greater than 1 mm; Step S3. The raw materials of metal Ni, Cr, Fe, Mo, Nb, Co, and graphite C are weighed according to the formula, and are placed in a vacuum induction furnace, and vacuumizing is started; when the vacuum degree reaches 10 Pa, the power of the vacuum induction furnace is adjusted to 20 kW, and heating is started for 20 min; vacuumizing is continued, and when the vacuum degree is less than 5 Pa, the power of the vacuum induction furnace is adjusted to 50 kW, the temperature of the molten pool is kept within 1600 DEG C, the alloy is slowly melted, and electromagnetic stirring is carried out; after the alloy is melted, the weighed raw materials of metal Al and Ti and the intermediate alloy powder prepared in step S2 are added, and the mass ratio of the added intermediate alloy and the raw materials is 0.2%:1, the power of the vacuum induction furnace is reduced to 35 kW, the temperature of the molten pool is kept at 1520 DEG C, and refining is carried out for 30 min and electromagnetic stirring is carried out for 2 h to further reduce the content of gaseous elements in the molten pool; the smelted alloy is poured under the protection of argon gas, and the pouring temperature is 1480 DEG C, and an electrode rod is obtained after cooling; Step S4. The electrode rod prepared in step S3 is subjected to electroslag remelting, the bottom of the electrode rod is welded to a dummy electrode, and is placed in an electroslag remelting furnace, and is melted by the resistance heat generated by the current passing through the molten slag, the metal droplets pass through the slag layer to reduce the content of various non-metallic impurities, and are solidified and crystallized in the crystallizer to form an ingot, and are demolded after being cooled for 3 h, and are air-cooled; the temperature of the molten slag added during electroslag remelting is 1300 DEG C, the working current is 3000 A, the working voltage is 50 V, and the molten slag comprises 70% CaF2, 15% CaO, and 15% Al2O3; Step S5. The ingot prepared in step S4 is subjected to high-temperature homogenization diffusion annealing to promote the dissolution of primary phases, and to eliminate the segregation of alloy elements, and the ingot is slowly heated from room temperature to 1160 DEG C, and is kept for 36 h, and after being taken out, is directly heated to 1200 DEG C and is kept for 36 h, and is air-cooled; Step S6. The ingot obtained in step S5 is circumferentially rolled and preheated in a heating furnace. It is then drawn to the desired size using a three-stage upsetting and drawing process to obtain the billet. Each upsetting and drawing process includes heating, upsetting, heating, and drawing. During the upsetting and drawing process, the average deformation of each upsetting pass is controlled at 42%, the heating temperature of each pass is controlled at 1140℃, and the holding time is 4h. During the drawing process, the heating temperature is controlled at 1140℃ for the first drawing pass, and at 1130℃ for the second drawing pass. The deformation is controlled at 44%, and the holding time is 4h. The final pass involves deformation and rounding, with the heating temperature controlled at 1120℃, the deformation controlled at 24%, and the holding time 4h. Step S7. After the forging billet obtained in step S6 is machined to the point where there are no cracks on the surface, it is subjected to solution aging treatment. The solution treatment temperature is 980℃, and it is held for 2 hours. Then it is taken out and water-cooled. The aging treatment temperature is 720℃. The bar is placed in a resistance furnace and held for 10 hours. Then it is cooled to 620℃ with the furnace at 50℃ / h. Then it is held for 8 hours. Then it is taken out and air-cooled.

[0026] The microstructure of the nickel-based superalloy rod 2 reinforced with nano-ceramic particles prepared in this embodiment is as follows: Figure 2 As shown, from Figure 2 It can be seen that the microstructure is equiaxed crystals with an average grain size of 20~30μm. The yield strength, tensile strength and elongation are 1145MPa, 1193MPa and 25.4%, respectively, and the room temperature hardness is 442HV.

[0027] Comparative Example 1 A method for preparing a high-temperature alloy rod includes the following steps: Step S1. Weigh the raw materials of metals Ni, Cr, Fe, Mo, Nb, Co, and graphite C according to the formula, and put the above raw materials into a vacuum induction furnace and start evacuation. When the vacuum degree reaches 10 Pa, adjust the power of the vacuum induction furnace to 20 kW and heat for 20 min. Continue evacuation. When the vacuum degree is less than 5 Pa, adjust the power of the vacuum induction furnace to 50 kW, keep the molten pool temperature below 1600℃, slowly melt the alloy and perform electromagnetic stirring. After the alloy melts, add the weighed raw materials of metals Al and Ti, reduce the power of the vacuum induction furnace to 35 kW, keep the molten pool temperature at 1520℃ and refine for 30 min and perform electromagnetic stirring for 2 h to further reduce the content of gaseous elements in the molten pool. Cast the molten alloy under the protection of argon gas at a casting temperature of 1480℃. After cooling, the electrode rod is obtained. Step S2. The electrode rod obtained in step S1 is subjected to electroslag remelting. The bottom of the electrode rod is welded to a dummy electrode and placed in an electroslag remelting furnace. The molten slag is melted by the resistance heat generated when the current passes through it. The molten metal droplets pass through the slag layer to reduce the content of various non-metallic impurities. The molten metal solidifies and crystallizes in the crystallizer to form an ingot. After cooling for 3 hours, the ingot is demolded and air-cooled. The temperature of the molten slag added during electroslag remelting is 1300℃, the working current is 3000A, the working voltage is 50V, and the molten slag includes 70% CaF2, 15% CaO, and 15% Al2O3. Step S3. The ingot obtained in step S2 is subjected to high-temperature homogenization diffusion annealing to promote the dissolution of the primary phase and eliminate the segregation of alloying elements. The ingot is slowly heated from room temperature to 1160°C and held for 36 hours. After the heating is completed, the temperature is directly raised to 1200°C and held for another 36 hours. Then it is taken out and air-cooled. Step S4. The ingot obtained in Step S3 is circumferentially rolled and preheated in a furnace before forging. It is then drawn to the desired dimensions using a three-stage upsetting and drawing process to obtain the billet. Each upsetting and drawing pass includes heating, upseting, heating again, and drawing. During the upsetting and drawing process, the average deformation of each upset pass is controlled at 42%, the heating temperature is controlled at 1140℃, and the holding time is 4 hours. During drawing, the heating temperature is controlled at 1140℃ for the first drawing pass, 1130℃ for the second drawing pass, the deformation is controlled at 44%, and the holding time is 4 hours. The final pass involves deformation and rounding, with the heating temperature controlled at 1120℃, the deformation controlled at 24%, and the holding time 4 hours. Step S5. After the forging billet obtained in step S6 is machined to the point where there are no cracks on the surface, it is subjected to solution aging treatment. The solution treatment temperature is 980℃, and it is held for 2 hours. Then it is taken out and water-cooled. The aging treatment temperature is 720℃. The bar is placed in a resistance furnace and held for 10 hours. Then it is cooled to 620℃ with the furnace at 50℃ / h. Then it is held for 8 hours and then air-cooled.

[0028] The microstructure of the nickel-based superalloy rod prepared in this comparative example is as follows: Figure 3 As shown, from Figure 3 It can be seen that the microstructure is equiaxed crystal with an average grain size of 70~80μm. The yield strength, tensile strength and elongation are 983MPa, 1071MPa and 23.1%, respectively, and the room temperature hardness is 401HV.

[0029] The chemical compositions of the high-temperature alloys of Examples 1-2 and Comparative Example 1 are shown in Table 1.

[0030] Table 1

[0031] The mechanical properties of the high-temperature alloys of Examples 1-2 and Comparative Example 1 at 650°C are shown in Table 2.

[0032] Table 2

[0033] As can be seen from Table 1 and Table 2, compared with the average grain size of the nickel-based superalloy rod prepared in Comparative Example 1, the average grain size is obviously refined and the hardness is obviously improved after adding the nano ceramic particles in Example 1 and Example 2; when the tensile test is carried out at 650 DEG C, the performance of the alloy prepared in the application is better than that of the alloy of Comparative Example 1.

[0034] Compared with the prior art, the application significantly improves the hardness, yield strength and tensile strength of the superalloy by the synergistic control of the ratio and process parameters while retaining the original smelting process, and can retain the original process and reduce the preparation cost. The added nano ceramic particles are uniformly dispersed, effectively refine the superalloy structure and control the distribution of precipitates, and the performance improvement effect is significant. The technology is suitable for high-temperature and high-load industrial environment and has excellent industrial application prospect.

[0035] Finally, it should be explained that the above specific embodiments are only used to illustrate the technical solutions of the application and not to limit it. Although the application has been described in detail with reference to the examples, it should be understood by those skilled in the art that the technical solutions of the application can be modified or replaced equivalently without departing from the spirit and scope of the technical solutions of the application, and they should be covered in the scope of the claims of the application.

Claims

1. A nanoceramic particle reinforced nickel-based superalloy rod, characterized in that, The nickel-based high-temperature alloy rod comprises the following components in percentage by mass: C: 0.015%~0.06%, Cr: 17%~21%, Mo: 2.8%~3.3%, Nb: 5.0%~5.5%, Ti: 0.75%~1.15%, Al: 0.3%~0.7%, Ni: 50%~55%, B≤0.006%, Co≤1.0%, Mn≤0.35%, Si≤0.35%, S≤0.002%, P≤0.005%, Mg≤0.005%, and the rest is Fe, and the total of the above is 100%.

2. A method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: The method comprises the following steps: Step S1. Al powder, Ti powder and B4C powder are mixed and then subjected to ball milling to obtain mixed powder; Step S2. The mixed powder is pressed into a compact, pure aluminum is placed in a medium-frequency furnace, the medium-frequency furnace is heated to 800~850℃, argon gas is passed to cover the melt, then the compact is immersed into the bottom of the melt for reaction, after the reaction is completed, the temperature of the melt is controlled at 800~850℃ and stirring is performed, and finally after cooling to room temperature, the intermediate alloy is taken out and crushed into granular form; Step S3. Metal Ni, Cr, Fe, Mo, Nb, Co, graphite C raw materials are weighed according to the content of each component of the nickel-based high-temperature alloy rod, and the above raw materials are placed in a vacuum induction furnace and vacuumizing is started, the temperature of the molten pool is maintained at 1550~1650℃, the alloy is slowly melted and electromagnetic stirring is performed; after the alloy is melted, the weighed metal Al, Ti raw materials and the intermediate alloy are added, the temperature of the molten pool is maintained at 1500~1550℃ and electromagnetic stirring is performed; the smelted alloy is poured under the protection of argon gas, and an electrode rod is obtained after cooling; Step S4. The electrode rod prepared in step S3 is subjected to electroslag remelting to form an ingot, and then after cooling for 2~3h, the ingot is demolded and air-cooled; Step S5. The ingot prepared in step S4 is subjected to high-temperature homogenization diffusion annealing, and then air-cooled; Step S6. The ingot after homogenization diffusion annealing in step S5 is subjected to circumferential surface rolling and grinding, pre-heating is performed through a heating furnace before forging, and multiple passes of upsetting and drawing are performed to the forged size to obtain a forged billet; Step S7. The forged billet prepared in step S6 is turned to be free of cracks on the surface, and then is sequentially subjected to solid solution treatment and aging treatment, and is taken out and air-cooled to obtain a nano ceramic particle reinforced nickel-based high-temperature alloy rod.

3. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: In step S1, the rotating speed of ball milling is 60~100r / min, the ball milling time is 15~25h, and the molar ratio of Al powder, Ti powder and B4C powder in the mixed powder is 4-4.5:2.5-3:1; the particle size of Ti powder is 20~40μm, the particle size of B4C powder is 5~15μm, and the particle size of Al powder is 20~30μm.

4. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: In step S2, the stirring time is 20~30min, and the particle diameter of the intermediate alloy is ≤1mm.

5. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: In step S3, the mass ratio of the intermediate alloy to the total weight of the raw materials is 0.1%~0.2%:1, and the pouring temperature is 1450~1480℃.

6. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: The temperature of the molten slag added in the electroslag remelting in step S4 is 1260-1320℃, the working current is 2800-3200A, the working voltage is 45-50V, and the molten slag comprises 70% CaF2, 15% CaO and 15% Al2O3.

7. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: The high-temperature homogenization diffusion annealing in step S5 specifically comprises the following steps: slowly heating the cast ingot from room temperature to 1160-1180℃, and keeping the temperature for 30-40h, then directly heating to 1200-1220℃ and keeping the temperature for 30-40h, and then taking out and air cooling.

8. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: In step S6, each upsetting and drawing process comprises the steps of heating, upsetting, heating and drawing, the average deformation amount of each upsetting process is controlled to be 40%-50% during the upsetting process, the heating temperature of each upsetting process is controlled to be 1130-1150℃, and the holding time is 2-4h; during the drawing process, the heating temperature of the first drawing process is controlled to be 1130-1150℃, the heating temperature of the second drawing process is controlled to be 1110-1130℃, the deformation amount is controlled to be 40%-50%, and the holding time is 2-4h, the last deformation and rounding process is performed, the heating temperature is controlled to be 1110-1130℃, the deformation amount is controlled to be 20%-30%, and the holding time is 2-4h, and the cross-sectional size of the alloy ingot after the forging is Φ300-320mm.

9. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: The temperature of the solid solution treatment in step S7 is 950-980℃, and the holding time is 120-140min.

10. The method of producing a nanoceramic particle reinforced nickel-based superalloy rod according to claim 1, characterized in that: The aging treatment in step S7 is specifically as follows: heating the forged blank after the solid solution treatment to 680-720℃, keeping the temperature for 8-10h, cooling to 600-620℃ at a rate of 50-55℃ / h, keeping the temperature for 8-10h, and then taking out and air cooling.

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