Heat treatment method of high-molybdenum-cobalt-nickel base alloy

Abstract

The invention relates to a heat treatment method of a high-molybdenum-cobalt-nickel-based alloy. The heat treatment method comprises the following steps: sequentially carrying out solution treatment and aging treatment on the high-molybdenum-cobalt-nickel-based alloy; and a high-molybdenum-cobalt-nickel-based alloy finished product is obtained. The heat preservation time of the solution treatment is t1 + a * D.omega1 * omega20.5 min, t1 is the basic heat preservation time of the solution treatment, the unit of t1 is min, the value range of a is 70-90, D is the effective thickness of the high-molybdenum-cobalt-nickel-based alloy, the unit of D is mm, the mass percent of the high-molybdenum-cobalt-nickel-based alloy is 100%, omega1 and omega2 are the mass percent of molybdenum and cobalt in the high-molybdenum-cobalt-nickel-based alloy respectively, and the sum of the mass percent of the omega1 and the mass percent of the cobalt in the high-molybdenum-cobalt-nickel-based alloy is 100%. The heat preservation time of the aging treatment is equal to t2 + b * D * omega10.3 * omega2min, t2 is the basic heat preservation time of the aging treatment, the unit of t2 is min, and the value range of b is 300-360. The heat preservation time of solution treatment and aging treatment is regulated and controlled according to the size of the high-molybdenum-cobalt-nickel-based alloy and the content of molybdenum and cobalt in the alloy, so that the high-molybdenum-cobalt-nickel-based alloy finished product subjected to heat treatment has good high-temperature durability and room-temperature tensile property at the same time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hot processing, in particular to a heat treatment method of high-molybdenum cobalt-nickel-based alloy. BACKGROUND

[0002] The molybdenum and cobalt contents of the high-molybdenum cobalt-nickel-based alloy are both more than 9%, and compared with ordinary nickel-based alloy, the solid solution stability thereof is better, and the high-molybdenum cobalt-nickel-based alloy performs outstandingly in long-term service applications such as turbine blades. At present, the high-molybdenum cobalt-nickel-based alloy is mainly used for manufacturing hot end components such as combustion chambers, guide vanes, turbine blades and turbine discs of aircraft engines, and can also be used for manufacturing structural parts such as aircraft engine bearings and seals.

[0003] In the performance evaluation process of the high-molybdenum cobalt-nickel-based alloy finished product, the room temperature tensile strength and the high-temperature enduring performance are two important parameters, but the room temperature tensile strength and the high-temperature enduring performance are a kind of mutually restrictive relationship. In general, the room temperature tensile strength is high but the high-temperature enduring performance is poor, or the high-temperature enduring performance is good but the room temperature tensile strength is low.

[0004] CN104004980A discloses a heat treatment process of a nickel-based precipitation hardening type high-temperature alloy, which comprises the following process steps: 1) heating the nickel-based precipitation hardening type high-temperature alloy to 480-520℃ in an air furnace, and keeping the temperature for 30-40 min to obtain a preheated high-temperature alloy product; 2) transferring the preheated high-temperature alloy product in step 1) to another heating furnace, which is heated to 1080-1100℃ in advance, and after the preheated high-temperature alloy product is put into the heating furnace, the temperature in the heating furnace is restored to 1080-1100℃, and then the timing is started, and the temperature is kept for 10-15 min, and the product is taken out and air-cooled to obtain a solid-solution high-temperature alloy product; 3) keeping the solid-solution high-temperature alloy product in step 2) at 740-760℃ for 3-5 hours, and cooling under argon atmosphere, and aging to obtain a heat-treated nickel-based precipitation hardening type high-temperature alloy finished product. It only discloses the heat treatment process of ordinary nickel-based alloy, and does not involve the development of the heat treatment process of the nickel-based alloy with high molybdenum and cobalt contents, and the tensile strength of the nickel-based precipitation hardening type high-temperature alloy finished product thereof is at most 1232 MPa, and the corresponding enduring performance is 35 h.

[0005] Therefore, it is necessary to develop a heat treatment process of high-molybdenum cobalt-nickel-based alloy, so that the room temperature tensile strength and the high-temperature enduring performance of the high-molybdenum cobalt-nickel-based alloy finished product after treatment can reach a better level. SUMMARY

[0006] To solve the above technical problems, the present application provides a heat treatment method of high-molybdenum cobalt-nickel-based alloy, which adjusts the holding time of solid solution treatment and aging treatment according to the size of the high-molybdenum cobalt-nickel-based alloy and the content of molybdenum and cobalt in the alloy, so that the high-molybdenum cobalt-nickel-based alloy product after heat treatment has good high-temperature endurance and room temperature tensile properties.

[0007] To achieve this purpose, the present application adopts the following technical solutions:

[0008] In a first aspect, the present application provides a heat treatment method of high-molybdenum cobalt-nickel-based alloy, which comprises: sequentially performing solid solution treatment and aging treatment on the high-molybdenum cobalt-nickel-based alloy; and obtaining a high-molybdenum cobalt-nickel-based alloy product.

[0009] The holding time of the solid solution treatment = t1 + a x D x ω1 x ω2 0.5 min, wherein t1 is the basic holding time of the solid solution treatment, the unit of t1 is min, the value range of a is 70-90, D is the effective thickness of the high-molybdenum cobalt-nickel-based alloy, the unit of D is mm, ω1 is the mass percentage of molybdenum in the high-molybdenum cobalt-nickel-based alloy, and ω2 is the mass percentage of cobalt in the high-molybdenum cobalt-nickel-based alloy, with the mass percentage of the high-molybdenum cobalt-nickel-based alloy being 100%;

[0010] The holding time of the aging treatment = t2 + b x D x ω1 x ω2 0.3 min, wherein t2 is the basic holding time of the aging treatment, the unit of t2 is min, and the value range of b is 300-360.

[0011] The value range of a is 70-90, for example, it can be 70, 72, 75, 78, 80, 83, 85, 87 or 90, and the value range of b is 300-360, for example, it can be 300, 310, 320, 330, 340, 350 or 360, but it is not limited to the listed values, and other values not listed in the above value range are also applicable.

[0012] The present application firstly carries out solid solution treatment on the high-molybdenum cobalt-nickel-based alloy, and controls the holding time of the solid solution treatment according to the size of the high-molybdenum cobalt-nickel-based alloy and the content of molybdenum and cobalt in the alloy, so that the high-molybdenum cobalt-nickel-based alloy is fully dissolved, the strengthening phase is dissolved into austenite, and the grain is prevented from growing excessively, so as to eliminate the unevenness of the as-cast or as-processed structure, form a uniform supersaturated solid solution, lay a foundation for subsequent aging treatment, and further carry out aging treatment on the high-molybdenum cobalt-nickel-based alloy, so that the supersaturated solid solution precipitates a high-density γ' or γ'' phase, and the holding time of the aging treatment is controlled according to the size of the high-molybdenum cobalt-nickel-based alloy and the content of molybdenum and cobalt in the alloy, so as to control the size, distribution and volume fraction of the precipitated phase, and finally make the high-molybdenum cobalt-nickel-based alloy product after heat treatment have good high-temperature durability and room temperature tensile properties at the same time.

[0013] Further, in the process of solid solution treatment, it is found that the holding time has a stronger correlation with the content of molybdenum, so that ω2 0.5 The above-mentioned control of the holding time can effectively control the case of excessive grain growth during the solid solution treatment. In the process of aging treatment, the holding time has a stronger correlation with the content of cobalt and a weaker correlation with the content of molybdenum, and it is found that ω1 0.3 The holding time is related to the content of molybdenum, and the holding time of the aging treatment is controlled, so as to control the size, distribution and volume fraction of the precipitated phase, and finally make the high-molybdenum cobalt-nickel-based alloy product after heat treatment have good high-temperature durability and room temperature tensile properties at the same time.

[0014] The high-molybdenum cobalt-nickel-based alloy in the present application refers to an alloy in which nickel is the main component, and the contents of molybdenum and cobalt are both more than 9%.

[0015] As a preferred technical solution of the present application, the mass percentage of molybdenum in the high-molybdenum cobalt-nickel-based alloy is 9-10.5%, for example, it can be 9%, 9.2%, 9.4%, 9.6%, 9.8%, 10%, 10.2% or 10.5%, but is not limited to the listed values, and other values not listed in the above value range are also applicable.

[0016] The mass percentage of molybdenum in the nickel-based alloy in the present application is 9-10.5%, which can improve the high-temperature creep resistance of the high-molybdenum cobalt-nickel-based alloy during solid solution treatment, and can also inhibit the precipitation of harmful phases and improve the long-term high-temperature service performance. If the mass percentage of molybdenum is less than 9%, the alloy will have insufficient creep resistance in a high-temperature and high-pressure environment, and will be prone to deformation failure. If the mass percentage of molybdenum is greater than 10.5%, the alloy hardness will increase, brittle phases will be promoted to precipitate, and the toughness and creep resistance will be reduced.

[0017] Preferably, the mass percentage of cobalt in the high-molybdenum cobalt nickel-based alloy is 9-11%, for example, it can be 9%, 9.5%, 10%, 10.5% or 11%, but is not limited to the listed values, and other values not listed in the above value range are also applicable.

[0018] The cobalt in the nickel-based alloy can reduce the stacking fault energy of the nickel-based alloy, promote dislocation cross-slip, thereby improving the high-temperature endurance strength and creep resistance, and the mass percentage of cobalt in the nickel-based alloy in the application is 9-11%, which can inhibit the precipitation of harmful phases and improve the long-term high-temperature service performance. At the same time, cobalt can synergistically act with Al and Ti to enhance the strengthening effect of the γ' phase (Ni3Al). If the mass percentage of cobalt is less than 9%, the alloy will have reduced creep resistance in a high-temperature high-stress environment, and will also cause the γ' phase (Ni3Al) to coarsen, thereby reducing long-term high-temperature stability. If the mass percentage of cobalt is greater than 11%, it will promote the precipitation of brittle phases such as σ phase and μ phase in certain temperature ranges, thereby reducing the toughness of the alloy.

[0019] Preferably, the mass ratio of molybdenum to cobalt in the high-molybdenum cobalt nickel-based alloy is (0.9-1.1):1, for example, it can be 0.9:1, 0.95:1, 1:1, 1.05:1 or 1.1:1, but is not limited to the listed values, and other values not listed in the above value range are also applicable.

[0020] By controlling the mass ratio of molybdenum to cobalt in the nickel-based alloy to be (0.9-1.1):1, the two elements can synergistically improve high-temperature performance, inhibit the precipitation of brittle phases such as σ phase and μ phase, and prolong service life. If the mass ratio of molybdenum to cobalt is less than 0.9:1, σ phase will precipitate during long-term high-temperature service, thereby reducing the toughness of the alloy. If the mass ratio of molybdenum to cobalt is greater than 1.1:1, the hardness of the alloy will increase, and the creep resistance of the alloy will decrease.

[0021] As a preferred technical solution of the application, the material of the high-molybdenum cobalt nickel-based alloy comprises M-252.

[0022] M-252 is a high-strength, heat-resistant and oxidation-resistant nickel-based alloy suitable for high-stress environments below 900°C. Its performance is highly dependent on solid solution and aging heat treatment control, and it plays an important role in the field of aircraft engines and energy equipment.

[0023] As a preferred technical solution of the application, the components of the high-molybdenum cobalt nickel-based alloy further include Ni, C, Si, Mn, P, S, Cr, Fe, Al, Ti and B.

[0024] Preferably, the high-molybdenum cobalt-nickel-based alloy comprises, in terms of 100% of the mass percentage of the high-molybdenum cobalt-nickel-based alloy, Ni 51.32-60.346%, C 0.1-0.2%, Si 0.03-0.5%, Mn 0.005-0.08%, P 0.012-0.015%, S 0.001-0.015%, Cr 18-20%, Fe 0.5-5%, Al 0.75-1.25%, Ti 2.25-2.75%, and B 0.003-0.01%, wherein the mass percentage of Ni can be 51.32%, 53%, 55%, 57%, or 60.346%, the mass percentage of C can be 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, or 0.2%, the mass percentage of Si can be 0.03%, 0.1%, 0.2%, 0.3%, 0.4%, or 0.5%, the mass percentage of Mn can be 0.005%, 0.02%, 0.04%, 0.06%, or 0.08%, the mass percentage of P can be 0.012, 0.013%, 0.014%, or 0.015%, the mass percentage of S can be 0.001%, 0.005%, 0.01%, 0.013%, or 0.015%, the mass percentage of Cr can be 18%, 18.5%, 19%, 19.5%, or 20%, the mass percentage of Fe can be 0.5%, 1%, 2%, 3%, 4%, or 5%, the mass percentage of Al can be 0.75%, 0.85%, 0.95%, 1.05%, 1.15%, or 1.25%, the mass percentage of Ti can be 2.25%, 2.35%, 2.45%, 2.55%, 2.65%, or 2.75%, and the mass percentage of B can be 0.003%, 0.005%, 0.007%, 0.009%, or 0.01%, but not only limited to the listed values, other values not listed within the above numerical ranges are also applicable.

[0025] As a preferred technical solution of the present application, the temperature of the solid solution treatment is 1150-1200°C, for example, it can be 1150°C, 1160°C, 1170°C, 1180°C, 1190°C, or 1200°C, but not only limited to the listed values, other values not listed within the above numerical ranges are also applicable.

[0026] Preferably, the temperature of the aging treatment is 800-850°C, for example, it can be 800°C, 810°C, 820°C, 830°C, 840°C, or 850°C, but not only limited to the listed values, other values not listed within the above numerical ranges are also applicable.

[0027] Preferably, the base holding time t1 of the solution treatment is 30-40 min, for example, it can be 30 min, 32 min, 34 min, 36 min, 38 min or 40 min, but not limited to the listed values, other values not listed in the above value range are also applicable.

[0028] Preferably, the base holding time t2 of the aging treatment is 40-60 min, for example, it can be 40 min, 45 min, 50 min, 55 min or 60 min, but not limited to the listed values, other values not listed in the above value range are also applicable.

[0029] The skilled in the art knows that the base holding time is related to the temperature of the corresponding treatment, generally when the treatment temperature is high, the base holding time is short.

[0030] As a preferred technical solution of the present application, the heating rate of the high-molybdenum cobalt-nickel-based alloy during the solution treatment is 50-100℃ / h, for example, it can be 50℃ / h, 60℃ / h, 70℃ / h, 80℃ / h, 90℃ / h or 100℃ / h, but not limited to the listed values, other values not listed in the above value range are also applicable.

[0031] By controlling the heating rate of the high-molybdenum cobalt-nickel-based alloy during the solution treatment to be 50-100℃ / h, the material can be uniformly heated, the internal stress can be reduced, the deformation or cracking caused by thermal stress can be avoided, at the same time, it can ensure that the strengthening phase is dissolved into austenite to form a uniform supersaturated solid solution. If the heating rate is less than 50℃ / h, the solution treatment time will be prolonged, and the production efficiency will be reduced. If the heating rate is greater than 100℃ / h, the material will be deformed or cracked due to excessive thermal stress, at the same time, the rapid heating will also lead to the incomplete dissolution of the strengthening phase due to the non-uniform local temperature, resulting in insufficient strength of the finished product after aging treatment, further, the rapid heating will also cause the overheating of some areas and the fine grains in other areas, affecting the consistency of mechanical properties, at the same time, it will also lead to the precipitation of harmful phases, affecting the high-temperature durability of the finished product.

[0032] Preferably, the heating rate of the high-molybdenum cobalt-nickel-based alloy during the aging treatment is 50-100℃ / h, for example, it can be 50℃ / h, 60℃ / h, 70℃ / h, 80℃ / h, 90℃ / h or 100℃ / h, but not limited to the listed values, other values not listed in the above value range are also applicable.

[0033] The application can make the supersaturated solid solution after solid solution treatment precipitate high-density γ' or γ" phase by controlling the heating rate of the aging treatment process of high-molybdenum cobalt-nickel-based alloy at 50-100℃ / h. If the heating rate is less than 50℃ / h, the aging treatment time will be prolonged, the production efficiency will be reduced, the alloy will be pre-precipitated, the coarse or irregular strengthening phase will be formed, and the strength of the finished product will be reduced. If the heating rate is greater than 100℃ / h, the γ' or γ" phase will be densely precipitated in the local overheated area, and insufficiently precipitated in other areas, so that the performance of the final product is uneven.

[0034] As a preferred technical solution of the application, the cooling process in the solid solution treatment and the aging treatment independently comprises air cooling.

[0035] Preferably, the cooling rate of air cooling in the solid solution treatment is 10-50℃ / min, for example, it can be 10℃ / min, 20℃ / min, 30℃ / min, 40℃ / min or 50℃ / min, but is not limited to the listed values, and other values not listed in the above value range are also applicable.

[0036] The application limits the cooling rate of air cooling in the solid solution treatment to 10-50℃ / min, rapidly cools the alloy after solid solution treatment, suppresses the precipitation of harmful phase, retains the supersaturated solid solution, and suppresses the abnormal growth of grains, so as to maintain a fine and uniform structure.

[0037] Preferably, the cooling rate of air cooling in the aging treatment is 10-50℃ / min, for example, it can be 10℃ / min, 20℃ / min, 30℃ / min, 40℃ / min or 50℃ / min, but is not limited to the listed values, and other values not listed in the above value range are also applicable.

[0038] The application limits the cooling rate of air cooling in the aging treatment to 10-50℃ / min, slowly cools the alloy after aging treatment, reduces the residual stress, forms a stable structure, and makes the high-molybdenum cobalt-nickel-based alloy after heat treatment have good high-temperature endurance performance and room temperature tensile performance at the same time.

[0039] As a preferred technical solution of the application, the heat treatment method comprises:

[0040] (1) placing the high-molybdenum cobalt-nickel-based alloy with the molybdenum and cobalt content both exceeding 9% into a heat treatment furnace with a temperature of 1150-1200℃, and performing solid solution treatment on the high-molybdenum cobalt-nickel-based alloy, wherein the heating rate of the high-molybdenum cobalt-nickel-based alloy in the solid solution treatment process is 50-100℃ / h, and after the temperature of the high-molybdenum cobalt-nickel-based alloy is raised to 1150-1200℃, the high-molybdenum cobalt-nickel-based alloy is kept at the temperature for t1+(70-90)×D·ω1·ω2 0.5min, and then cooled to 20-25 DEG C at a rate of 10-50 DEG C / min to obtain the solution-treated alloy;

[0041] (2) placing the solution-treated alloy into a heat treatment furnace at a temperature of 800-850 DEG C for aging treatment, wherein the solution-treated alloy is heated at a rate of 50-100 DEG C / h during the aging treatment, and after the temperature of the solution-treated alloy is raised to 800-850 DEG C, the solution-treated alloy is kept at the temperature for t2+(300-360)xD*ω1 0.3 min, and then cooled to 20-25 DEG C at a rate of 10-50 DEG C / min to obtain the solution-treated alloy;

[0042] In a second aspect, the present application provides a high-molybdenum cobalt-nickel-based alloy product, which is obtained by the heat treatment method of the first aspect.

[0043] The high-molybdenum cobalt-nickel-based alloy product obtained by the present application has good high-temperature endurance and room-temperature tensile properties.

[0044] As a preferred technical solution of the present application, the tensile strength of the high-molybdenum cobalt-nickel-based alloy product is ≥1100 MPa, and the endurance time of the high-molybdenum cobalt-nickel-based alloy product is ≥300 h, wherein the tensile strength can be 1100 MPa, 1120 MPa, 1140 MPa, 1160 MPa, 1180 MPa, 1200 MPa or 1220 MPa, and the endurance time can be 300 h, 310 h, 320 h, 330 h, 340 h or 350 h, but is not limited to the listed values, and other values not listed in the above range are also applicable.

[0045] Compared with the prior art, the present application has at least the following beneficial effects:

[0046] The present application controls the holding time of solution treatment and aging treatment according to the size of the high-molybdenum cobalt-nickel-based alloy and the content of molybdenum and cobalt in the alloy, so that the high-molybdenum cobalt-nickel-based alloy product after heat treatment has good high-temperature endurance and room-temperature tensile properties, wherein the high-temperature endurance time is ≥300 h, and the tensile strength is ≥1100 MPa. DETAILED DESCRIPTION

[0047] To facilitate understanding of the present application, the present application lists the following examples. It should be understood by those skilled in the art that the examples are only to help understand the present application and should not be regarded as a specific limitation on the present application.

[0048] Example 1

[0049] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, the mass percentage of molybdenum ω1 and the mass percentage of cobalt ω2 in the high-molybdenum cobalt-nickel-based alloy are each 10% in 100% of the mass percentage of the high-molybdenum cobalt-nickel-based alloy, and the heat treatment method comprises the following steps:

[0050] (1) placing the high-molybdenum cobalt-nickel-based alloy with an effective thickness D of 43 mm into a heat treatment furnace with a temperature of 1170 ℃, and performing solid solution treatment on the high-molybdenum cobalt-nickel-based alloy, so that the heating rate of the high-molybdenum cobalt-nickel-based alloy during the solid solution treatment is 80 ℃ / h, after the temperature of the high-molybdenum cobalt-nickel-based alloy is raised to 1170 ℃, the high-molybdenum cobalt-nickel-based alloy is kept at 1170 ℃ for t1+80×D·ω1·ω2 0.5 min=35+80×43×0.1×0.1 0.5 min=144 min, and then air cooling at a rate of 30 ℃ / min to 25 ℃ to obtain an alloy after solid solution treatment;

[0051] (2) placing the alloy after solid solution treatment into a heat treatment furnace with a temperature of 820 ℃ to perform aging treatment, so that the heating rate of the alloy after solid solution treatment during the aging treatment is 70 ℃ / h, after the temperature of the alloy after solid solution treatment is raised to 820 ℃, the alloy after solid solution treatment is kept at 820 ℃ for t2+330×D·ω1 0.3 ·ω2min=50+330×43×0.1 0.3 ×0.1 min=761 min, and then air cooling at a rate of 20 ℃ / min to 20 ℃ to obtain a high-molybdenum cobalt-nickel-based alloy product.

[0052] The material of the high-molybdenum cobalt-nickel-based alloy comprises M-252, and the high-molybdenum cobalt-nickel-based alloy further comprises, in 100% of the mass percentage of the high-molybdenum cobalt-nickel-based alloy, Ni 54%, C 0.15%, Si 0.2%, Mn 0.04%, P 0.014%, S 0.01%, Cr 19%, Fe 3%, Al 1%, Ti 2.5% and B 0.005%.

[0053] Embodiment 2

[0054] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, the mass percentage of molybdenum ω1 in the high-molybdenum cobalt-nickel-based alloy is 10.5% in 100% of the mass percentage of the high-molybdenum cobalt-nickel-based alloy, the mass percentage of cobalt ω2 in the high-molybdenum cobalt-nickel-based alloy is 9%, and the heat treatment method comprises the following steps:

[0055] (1) put high-molybdenum cobalt-nickel-based alloy with effective thickness D of 40 mm into a heat treatment furnace with a temperature of 1150 °C, and perform solid solution treatment on the high-molybdenum cobalt-nickel-based alloy, so that the heating rate of the high-molybdenum cobalt-nickel-based alloy during the solid solution treatment is 50 °C / h, after the temperature of the high-molybdenum cobalt-nickel-based alloy rises to 1150 °C, the high-molybdenum cobalt-nickel-based alloy is kept at the temperature for t1+70×D·ω1·ω2 0.5 min=40+70×40×0.105×0.09 0.5 min=128 min, and then air-cooled at a rate of 10 °C / min to 20 °C to obtain the alloy after solid solution treatment;

[0056] (2) put the alloy after solid solution treatment into a heat treatment furnace with a temperature of 850 °C, and perform aging treatment on the alloy after solid solution treatment, so that the heating rate of the alloy after solid solution treatment during the aging treatment is 100 °C / h, after the temperature of the alloy after solid solution treatment rises to 850 °C, the alloy after solid solution treatment is kept at the temperature for t2+360×D·ω1 0.3 ·ω2min=40+360×40×0.105 0.3 ×0.09 min=699 min, and then air-cooled at a rate of 50 °C / min to 20 °C to obtain the high-molybdenum cobalt-nickel-based alloy product.

[0057] The material of the high-molybdenum cobalt-nickel-based alloy includes M-252, and the high-molybdenum cobalt-nickel-based alloy further includes, with the mass percentage of the high-molybdenum cobalt-nickel-based alloy being 100%, Ni 51.32%, C 0.2%, Si 0.5%, Mn 0.08%, P 0.015%, S 0.015%, Cr 20%, Fe 4.86%, Al 1.25%, Ti 2.25%, and B 0.003%.

[0058] Example 3

[0059] The embodiment provides a heat treatment method of high-molybdenum cobalt-nickel-based alloy, the mass percentage ω1 of molybdenum in the high-molybdenum cobalt-nickel-based alloy is 9% with the mass percentage of the high-molybdenum cobalt-nickel-based alloy being 100%, the mass percentage ω2 of cobalt in the high-molybdenum cobalt-nickel-based alloy is 11%, and the heat treatment method comprises the following steps:

[0060] (1) put high-molybdenum cobalt-nickel-based alloy with effective thickness D of 45 mm into a heat treatment furnace with a temperature of 1200 °C, and perform solid solution treatment on the high-molybdenum cobalt-nickel-based alloy, so that the heating rate of the high-molybdenum cobalt-nickel-based alloy during the solid solution treatment is 100 °C / h, after the temperature of the high-molybdenum cobalt-nickel-based alloy rises to 1200 °C, the high-molybdenum cobalt-nickel-based alloy is kept at the temperature for t1+90×D·ω1·ω2 0.5 min=30+90×45×0.09×0.11 0.5min = 151 min, and then air-cooled at a rate of 50°C / min to 25°C to obtain the solution-treated alloy;

[0061] (2) The solution-treated alloy is placed in a heat treatment furnace at a temperature of 800°C for aging treatment, so that the heating rate of the solution-treated alloy during the aging treatment is 50°C / h, and after the temperature of the solution-treated alloy rises to 800°C, the solution-treated alloy is kept at this temperature for t2+300×D·ω1 0.3 ·ω2min = 60 + 300 x 45 x 0.09 0.3 x 0.11 min = 781 min, and then air-cooled at a rate of 10°C / min to 25°C to obtain the high-molybdenum cobalt-nickel-based alloy product.

[0062] The material of the high-molybdenum cobalt-nickel-based alloy includes M-252, and the high-molybdenum cobalt-nickel-based alloy further includes, with the mass percentage of the high-molybdenum cobalt-nickel-based alloy being 100%, Ni 58.3%, C 0.1%, Si 0.03%, Mn 0.005%, P 0.012%, S 0.001%, Cr 18%, Fe 0.5%, Al 0.75%, Ti 2.25%, and B 0.003%.

[0063] Example 4

[0064] The present example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from example 1 only in that the mass percentage ω1 of molybdenum in the high-molybdenum cobalt-nickel-based alloy is adjusted from 10% to 5%, the reduction is proportionally distributed to other components of the high-molybdenum cobalt-nickel-based alloy, i.e., the mass ratio of molybdenum to cobalt in the high-molybdenum cobalt-nickel-based alloy is 0.5:1, the holding time for solution treatment is correspondingly adjusted to 91 min, the holding time for aging treatment is correspondingly adjusted to 697 min, and the rest is the same as example 1.

[0065] Example 5

[0066] The present example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from example 1 only in that the mass percentage ω1 of molybdenum in the high-molybdenum cobalt-nickel-based alloy is adjusted from 10% to 15%, the increase is proportionally deducted from other components of the high-molybdenum cobalt-nickel-based alloy, i.e., the mass ratio of molybdenum to cobalt in the high-molybdenum cobalt-nickel-based alloy is 1.5:1, the holding time for solution treatment is correspondingly adjusted to 193 min, the holding time for aging treatment is correspondingly adjusted to 854 min, and the rest is the same as example 1.

[0067] Example 6

[0068] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that the mass percentage ω2 of cobalt in the high-molybdenum cobalt-nickel-based alloy is adjusted from 10% to 6%, the reduction is proportionally distributed to other components of the high-molybdenum cobalt-nickel-based alloy, that is, the mass ratio of molybdenum to cobalt in the high-molybdenum cobalt-nickel-based alloy is 0.6:1, the holding time of the solid solution treatment is correspondingly adjusted to 123 min, the holding time of the aging treatment is correspondingly adjusted to 508 min, and the rest is the same as the embodiment 1.

[0069] Embodiment 7

[0070] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that the mass percentage ω2 of cobalt in the high-molybdenum cobalt-nickel-based alloy is adjusted from 10% to 16%, the increase is proportionally distributed to other components of the high-molybdenum cobalt-nickel-based alloy, that is, the mass ratio of molybdenum to cobalt in the high-molybdenum cobalt-nickel-based alloy is 1.6:1, the holding time of the solid solution treatment is correspondingly adjusted to 163 min, the holding time of the aging treatment is correspondingly adjusted to 1232 min, and the rest is the same as the embodiment 1.

[0071] Embodiment 8

[0072] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that the temperature of the solid solution treatment in the step (1) is 1100 DEG C, and the rest is the same as the embodiment 1.

[0073] Embodiment 9

[0074] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that the temperature of the aging treatment in the step (2) is 750 DEG C, and the rest is the same as the embodiment 1.

[0075] Embodiment 10

[0076] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that the heating rate of the high-molybdenum cobalt-nickel-based alloy in the solid solution treatment process in the step (1) is adjusted from 80 DEG C / h to 40 DEG C / h, and the rest is the same as the embodiment 1.

[0077] Embodiment 11

[0078] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that the heating rate of the high-molybdenum cobalt-nickel-based alloy in the solid solution treatment process in the step (1) is adjusted from 80 DEG C / h to 120 DEG C / h, and the rest is the same as the embodiment 1.

[0079] Embodiment 12

[0080] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that, except that the temperature increasing rate of the high-molybdenum cobalt-nickel-based alloy in the aging treatment process in step (2) is adjusted from 70 DEG C / min to 30 DEG C / min, the rest is the same as the embodiment 1.

[0081] Example 13

[0082] The embodiment provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that, except that the temperature increasing rate of the high-molybdenum cobalt-nickel-based alloy in the aging treatment process in step (2) is adjusted from 70 DEG C / min to 120 DEG C / min, the rest is the same as the embodiment 1.

[0083] Comparative Example 1

[0084] The comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that, except that the holding time of the high-molybdenum cobalt-nickel-based alloy in the solid solution treatment process in step (1) is t1+80xD*ω1*ω2 min=35+80*43*0.1*0.1 min=69 min, the rest is the same as the embodiment 1.

[0085] Comparative Example 2

[0086] The comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that, except that the holding time of the high-molybdenum cobalt-nickel-based alloy in the solid solution treatment process in step (1) is t1+40xD*ω1*ω2 0.5 min=35+40*43*0.1*0.1 0.5 min=89 min, the rest is the same as the embodiment 1.

[0087] Comparative Example 3

[0088] The comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that, except that the holding time of the high-molybdenum cobalt-nickel-based alloy in the solid solution treatment process in step (1) is t1+120xD*ω1*ω2 0.5 min=35+120*43*0.1*0.1 0.5 min=198 min, the rest is the same as the embodiment 1.

[0089] Comparative Example 4

[0090] The comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from the embodiment 1 only in that, except that the holding time of the high-molybdenum cobalt-nickel-based alloy in the aging treatment process in step (2) is t2+330xD*ω1*ω2 min=50+330*43*0.1*0.1 min=192 min, the rest is the same as the embodiment 1.

[0091] Comparative Example 5

[0092] The present comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from Example 1 only in that, except that the holding time of the high-molybdenum cobalt-nickel-based alloy during the aging treatment in step (2) is t2+ 200 x D x ω1 0.3 x 0.1 min = 481 min, the rest is the same as Example 1. 0.3

[0093] Comparative Example 6

[0094] The present comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from Example 1 only in that, except that the holding time of the high-molybdenum cobalt-nickel-based alloy during the aging treatment in step (2) is t2+ 500 x D x ω1 0.3 x 0.1 min = 1127 min, the rest is the same as Example 1. 0.3

[0095] Comparative Example 7

[0096] The present comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from Example 1 only in that, except that the effective thickness D of the high-molybdenum cobalt-nickel-based alloy is 30 mm, and the holding time of the solution treatment in step (1) is 144 min, and the holding time during the aging treatment in step (2) is 761 min, the rest is the same as Example 1.

[0097] Comparative Example 8

[0098] The present comparative example provides a heat treatment method of a high-molybdenum cobalt-nickel-based alloy, which is different from Example 1 only in that, except that the effective thickness D of the high-molybdenum cobalt-nickel-based alloy is 60 mm, and the holding time of the solution treatment in step (1) is 144 min, and the holding time during the aging treatment in step (2) is 761 min, the rest is the same as Example 1.

[0099] The high-temperature stress rupture properties and room temperature tensile properties of the high-molybdenum cobalt-nickel-based alloy finished products obtained by Examples 1-13 and Comparative Examples 1-8 were tested, wherein the high-temperature stress rupture properties were tested according to ASTM E139, and the room temperature tensile properties were tested according to ASTM E8, and the test results are shown in Table 1.

[0100] Table 1

[0101]

[0102] ​​

[0103] From the test results, it can be seen that:

[0104] (1) From Examples 1 to 3, it can be seen that, according to the size of the high-molybdenum cobalt-nickel-based alloy and the content of molybdenum and cobalt in the alloy, the holding time of the solid solution treatment and the aging treatment is regulated, so that the high-molybdenum cobalt-nickel-based alloy product after heat treatment has good high-temperature endurance performance and room temperature tensile performance, wherein the high-temperature endurance time is ≥343.4h, and the tensile strength is ≥1177MPa.

[0105] (2) From Examples 1 and 4-7, it can be seen that, by controlling the mass ratio of molybdenum and cobalt in the nickel-based alloy (0.9-1.1):1, the high-temperature performance can be improved, the brittle phase such as σ phase and μ phase can be inhibited, and the service life can be prolonged, so that the high-molybdenum cobalt-nickel-based alloy product after heat treatment has good high-temperature endurance performance and room temperature tensile performance.

[0106] (3) From Examples 1 and 8-9, it can be seen that, in Example 1, the solid solution treatment temperature in step (1) is 1170℃, and the aging treatment temperature is 820℃, and the tensile strength of the high-molybdenum cobalt-nickel-based alloy product after heat treatment is 1214MPa, and the high-temperature endurance time is 343.4h; while in Example 8, the solid solution treatment temperature in step (1) is 1100℃, and the tensile strength of the high-molybdenum cobalt-nickel-based alloy product after heat treatment is 1322MPa, and the high-temperature endurance time is 195.8h, and in Example 9, the aging treatment temperature in step (1) is 750℃, and the tensile strength of the high-molybdenum cobalt-nickel-based alloy product after heat treatment is 1255MPa, and the high-temperature endurance time is 321.7h, which shows that, by controlling the solid solution treatment and aging treatment temperature of the high-molybdenum cobalt-nickel-based alloy, the high-molybdenum cobalt-nickel-based alloy product after heat treatment has good high-temperature endurance performance and room temperature tensile performance.

[0107] (4) By example 1 and example 10-11 can be seen, the heating rate in the solid solution treatment process in example 1 is 80 ℃ / h, the tensile strength of the high molybdenum cobalt nickel-based alloy finished product after heat treatment is 1214 MPa, and the high temperature enduring time is 343.4 h;While the heating rate in the solid solution treatment process in example 10 is 40 ℃ / h, the tensile strength of the high molybdenum cobalt nickel-based alloy finished product after heat treatment is 1031 MPa, and the high temperature enduring time is 433.2 h, the heating rate in the solid solution treatment process in example 11 is 120 ℃ / h, the tensile strength of the high molybdenum cobalt nickel-based alloy finished product after heat treatment is 1305 MPa, and the high temperature enduring time is 259.4 h, thus indicating that, by controlling the heating rate of the high molybdenum cobalt nickel-based alloy in the solid solution treatment process to be 50-100 ℃ / h, the material can be uniformly heated, and the internal stress can be reduced, so as to avoid deformation or cracking caused by thermal stress, and at the same time, the strengthening phase can be dissolved into austenite to form a uniform supersaturated solid solution, so that the high molybdenum cobalt nickel-based alloy finished product after heat treatment has good high temperature enduring performance and room temperature tensile performance at the same time.

[0108] (5) By example 1 and example 12-13 can be seen, the heating rate in the aging treatment process in example 1 is 70 ℃ / h, the tensile strength of the high molybdenum cobalt nickel-based alloy finished product after heat treatment is 1214 MPa, and the high temperature enduring time is 343.4 h;While the heating rate in the aging treatment process in example 12 is 30 ℃ / h, the tensile strength of the high molybdenum cobalt nickel-based alloy finished product after heat treatment is 1053 MPa, and the high temperature enduring time is 403.3 h, the heating rate in the aging treatment process in example 13 is 120 ℃ / h, the tensile strength of the high molybdenum cobalt nickel-based alloy finished product after heat treatment is 1297 MPa, and the high temperature enduring time is 277.2 h, thus indicating that, by controlling the heating rate of the high molybdenum cobalt nickel-based alloy in the aging treatment process to be 50-100 ℃ / h, the supersaturated solid solution after solid solution treatment can precipitate high-density γ' or γ'' phase, so that the high molybdenum cobalt nickel-based alloy finished product after heat treatment has good high temperature enduring performance and room temperature tensile performance at the same time.

[0109] (6) By example 1 and comparative example 1-3 can be seen, the holding time of the solid solution treatment is regulated according to the size of the high molybdenum cobalt nickel-based alloy and the content of molybdenum and cobalt in the alloy, so that the high molybdenum cobalt nickel-based alloy finished product after heat treatment has good high temperature enduring performance and room temperature tensile performance at the same time.

[0110] (7) By example 1 and comparative example 4-6 can be seen, the holding time of the aging treatment is regulated according to the size of the high molybdenum cobalt nickel-based alloy and the content of molybdenum and cobalt in the alloy, so that the high molybdenum cobalt nickel-based alloy finished product after heat treatment has good high temperature enduring performance and room temperature tensile performance at the same time.

[0111] (8) It can be seen from the embodiment 1 and the comparative examples 7-8 that, according to the size of the high-molybdenum cobalt-nickel-based alloy, the holding time of the solid solution treatment and the aging treatment is regulated, so that the high-molybdenum cobalt-nickel-based alloy product after heat treatment has good high-temperature durability and room temperature tensile properties at the same time.

[0112] In summary, according to the size of the high-molybdenum cobalt-nickel-based alloy and the content of molybdenum and cobalt in the alloy, the holding time of the solid solution treatment and the aging treatment is regulated, so that the high-molybdenum cobalt-nickel-based alloy product after heat treatment has good high-temperature durability and room temperature tensile properties at the same time, wherein the high-temperature durability is ≥ 300 h, and the tensile strength is ≥ 1100 MPa.

[0113] The applicant declares that the above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and it should be understood by those skilled in the art that any changes or replacements within the technical scope disclosed by the present application can be easily thought of by those skilled in the art, and all fall within the protection scope and disclosure scope of the present application.

Claims

1. A heat treatment method for a high-molybdenum cobalt-nickel based alloy, characterized in that, The heat treatment method includes: sequentially performing solution treatment and aging treatment on the high-molybdenum cobalt-nickel-based alloy to obtain the finished high-molybdenum cobalt-nickel-based alloy; The heat treatment holding time is: t1 + a × D·ω1·ω2 0.5 min, where t1 is the basic heat preservation time of the solution treatment, and the unit of t1 is min; the value of a ranges from 70 to 90; D is the effective thickness of the high molybdenum cobalt nickel-based alloy, and the unit of D is mm; ω1 is the mass percentage of molybdenum in the high molybdenum cobalt nickel-based alloy, and ω2 is the mass percentage of cobalt in the high molybdenum cobalt nickel-based alloy, with the mass percentage of the high molybdenum cobalt nickel-based alloy being 100%; The heat preservation time for the aging treatment = t2 + b × D·ω1 0.3 ·ω2min, where t2 is the basic heat preservation time of the aging treatment, the unit of t2 is min, and the value of b ranges from 300 to 360.

2. The heat treatment method according to claim 1, characterized in that, The molybdenum content in the high-molybdenum cobalt-nickel based alloy is 9–10.5% by mass. Preferably, the mass percentage of cobalt in the high-molybdenum cobalt-nickel-based alloy is 9-11%; Preferably, the mass ratio of molybdenum to cobalt in the high-molybdenum cobalt-nickel based alloy is (0.9-1.1):

1.

3. The heat treatment method according to claim 1 or 2, characterized in that, The high-molybdenum cobalt-nickel based alloy is made of material M-252.

4. The heat treatment method according to any one of claims 1-3, characterized in that, The high-molybdenum cobalt-nickel-based alloy also includes Ni, C, Si, Mn, P, S, Cr, Fe, Al, Ti and B. Preferably, based on 100% by mass, the high-molybdenum cobalt-nickel-based alloy comprises 51.32–60.346% Ni, 0.1–0.2% C, 0.03–0.5% Si, 0.005–0.08% Mn, 0.012–0.015% P, 0.001–0.015% S, 18–20% Cr, 0.5–5% Fe, 0.75–1.25% Al, 2.25–2.75% Ti, and 0.003–0.01% B.

5. The heat treatment method according to any one of claims 1-4, characterized in that, The solution treatment temperature is 1150–1200℃; Preferably, the aging treatment temperature is 800–850°C; Preferably, the basic heat preservation time t1 for the solution treatment is 30 to 40 minutes; Preferably, the basic heat preservation time t2 of the aging treatment is 40 to 60 minutes.

6. The heat treatment method according to any one of claims 1-5, characterized in that, The heating rate of the high-molybdenum cobalt-nickel-based alloy during the solution treatment process is 50–100 °C / h. Preferably, the heating rate of the high-molybdenum cobalt-nickel-based alloy during the aging treatment is 50–100 °C / h.

7. The heat treatment method according to any one of claims 1-6, characterized in that, The cooling processes in the solution treatment and the aging treatment each independently include air cooling; Preferably, the air cooling rate during the solution treatment is 10–50 °C / min; Preferably, the air cooling rate in the aging process is 10–50 °C / min.

8. The heat treatment method according to any one of claims 1-7, characterized in that, The heat treatment method includes: (1) A high-molybdenum cobalt-nickel-based alloy with molybdenum and cobalt contents both exceeding 9% is placed in a heat treatment furnace at a temperature of 1150–1200°C to perform a solution treatment. During the solution treatment, the heating rate of the high-molybdenum cobalt-nickel-based alloy is 50–100°C / h. After the temperature of the high-molybdenum cobalt-nickel-based alloy reaches 1150–1200°C, it is held at that temperature for t1+(70–90)×D·ω1·ω2. 0.5 min, and then cool to 20-25℃ at a rate of 10-50℃ / min to obtain the solution-treated alloy; (2) The solution-treated alloy is placed in a heat treatment furnace at a temperature of 800–850°C for aging treatment. During the aging treatment, the heating rate of the solution-treated alloy is 50–100°C / h. After the temperature of the solution-treated alloy reaches 800–850°C, it is held at that temperature for t2 + (300–360) × D·ω1 0.3 ·ω2min, and then cool to 20-25℃ at a rate of 10-50℃ / min to obtain the high-molybdenum cobalt-nickel based alloy product.

9. A high-molybdenum cobalt-nickel based alloy product, characterized in that, The high-molybdenum cobalt-nickel-based alloy product is obtained by the heat treatment method described in any one of claims 1-8.

10. The high-molybdenum cobalt-nickel based alloy product according to claim 9, characterized in that, The high-molybdenum cobalt-nickel based alloy product has a tensile strength ≥1100MPa and a creep rupture time ≥300h.

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