Method for improving damping performance of FeMn-based alloy and FeMn-based alloy thereof

Abstract

The invention provides a method for improving the damping performance of a FeMn-based alloy and the FeMn-based alloy. The method for improving the damping performance of the FeMn-based alloy comprises the following steps: stretching the FeMn-based alloy; wherein in the stretching process, stacking faults and twin crystals are introduced into the FeMn-based alloy. According to the method, the stacking fault and the twin crystal are introduced into the FeMn-based alloy through stretching, and the stacking fault energy is changed and the phase change free energy is improved through the stacking fault and the twin crystal, so that a close-packed hexagonal structure in the FeMn-based alloy is prevented from being converted into a face-centered cubic structure, and the damping performance of the FeMn-based alloy is improved; therefore, the problems of complex process flow and high cost caused by regulating and controlling components and adding elements are avoided.

Description

Technical Field

[0001] The invention relates to a method for improving the damping performance of a FeMn-based alloy and the FeMn-based alloy. Background Art

[0002] At present, metal damping materials are the most widely used in damping materials. Among them, damping alloy is a functional structural material widely used in the field of vibration reduction and noise reduction with broad prospects. It not only has the strength of structural materials, but also can use various microscopic physical mechanisms inside the alloy to convert external vibration energy into heat energy dissipation.

[0003] Currently, metal damping alloys include complex phase type, twin type, dislocation type, ferromagnetic type, FeMn-based, shape memory alloy (SMA) and other alloys. Most of the alloys studied are based on iron-based, copper-based and nickel-titanium-based SMA. Although SMA can be used as a damping material, there are still many problems that limit its use.

[0004] For example, the publication number is CN115323240A, and the name is a high-strength and tough metastable two-phase FeMnCrCo high-entropy alloy and its preparation method. First, the stacking fault energy of the high-entropy alloy is adjusted by controlling the atomic percentage variation range of the Mn element content (31%-36%), and the phase composition in the alloy is controlled. Then, through heat treatment and rolling processes, it is made to obtain a good match between strength and plasticity. The publication number is CN106756445A, and the name is an additive for improving the corrosion resistance of Fe-Mn-based high-damping alloys and a method for using the additive. An additive for smelting Fe-Mn-based high-damping alloys is provided. The use of the additive can reduce the corrosion rate of Fe-Mn-based high-damping alloys by more than 10 times in marine environments.

[0005] It can be seen that the current technology mainly focuses on enhancing damping performance by adjusting material composition and adding specific elements. However, these methods are not only complex and costly, but also difficult to effectively balance economic costs while pursuing improved damping performance. More importantly, the improvement of damping performance is highly dependent on controlling the composition, but the accuracy of composition control is very low, which affects the effect of improving damping performance. Summary of the invention

[0006] The present invention aims to solve the problem of complicated process flow and high cost caused by adjusting composition and adding elements, and provides a method for improving the damping performance of FeMn-based alloy and FeMn-based alloy thereof.

[0007] The technical method of the present invention is as follows:

[0008] The invention provides a method for improving the damping performance of a FeMn-based alloy. The method comprises: stretching the FeMn-based alloy; wherein, during the stretching process, stacking faults and twins are introduced into the FeMn-based alloy.

[0009] Optionally, the stacking faults and twins are introduced into the FeMn-based alloy to hinder the close-packed hexagonal structure in the FeMn-based alloy from transforming into a face-centered cubic structure.

[0010] Optionally, the stretching formula (1) is

[0011] Y = a*b% (1);

[0012] Wherein, Y is the stretched length, a is the length of the FeMn-based alloy before stretching, b is the stretching rate, and 1<b≤35.

[0013] Optionally, 1<b≤20.

[0014] Optionally, the stretching is performed using a stretching machine.

[0015] Optionally, during the stretching process, the stretching machine clamps both ends of the FeMn-based alloy, and at least one end is used for stretching.

[0016] Optionally, the FeMn-based alloy is Fe 65-x Mn 20 Cr 15 Co x Alloy; wherein x is 5-30.

[0017] Optionally, x is 5, 10, 15, 20, 25, or 30.

[0018] Optionally, the FeMn-based alloy is at least one of a cast alloy, an annealed alloy, and a nitrided alloy.

[0019] The present invention also provides a FeMn-based alloy, which is prepared by the above method for improving the damping performance of the FeMn-based alloy. The FeMn-based alloy damping is applied at a temperature of room temperature to 300° C., and the damping value is greater than or equal to 0.015.

[0020] The beneficial effects of the present invention are:

[0021] 1. The present invention introduces stacking faults and twins into the FeMn-based alloy by stretching, changes the stacking fault energy and improves the phase transition free energy through the stacking faults and twins, thereby hindering the transformation of the close-packed hexagonal structure in the FeMn-based alloy into a face-centered cubic structure, improving the damping performance of the FeMn-based alloy, thereby avoiding the problem of complex process flow and high cost caused by adjusting the composition and adding elements.

[0022] 2. Compared with the alloy with a damping value less than 0.01 in the prior art, the present invention increases the damping value to greater than or equal to 0.015 (a high damping performance alloy), thereby making the damping performance of the alloy better and having a wider range of application scenarios.

[0023] 3. The present invention introduces stacking faults and twins into the FeMn-based alloy through stretching, changes the stacking fault energy and increases the phase transition free energy through stacking faults and twins, thereby hindering the transformation of the close-packed hexagonal structure in the FeMn-based alloy into a face-centered cubic structure, improving the damping performance of the FeMn-based alloy, and overcoming the problem that the use temperature is limited to 200°C in the prior art. The present invention can increase the temperature to 300°C, expanding the range of the use temperature, so that the alloy can be used in more scenarios.

[0024] 4. During the stretching process of the present invention, the stretching machine clamps both ends of the FeMn-based alloy, and at least one end is used for stretching, thereby ensuring that the stretching amount is controllable and the stretching process is more uniform, so that the overall performance is more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The unstretched cast Fe in Examples 1-12 of the present invention 65-x Mn 20 Cr 15 Co x X-ray diffraction patterns of (x=5,10,15,20,25,30) alloys;

[0026] Figure 2 The unstretched annealed Fe 65-x Mn 20 Cr 15 Co x X-ray diffraction patterns of (x=5,10,15,20,25,30) alloys;

[0027] Figure 3 The unstretched cast Fe in Examples 1-12 of the present invention 65-x Mn 20 Cr 15 Co x Differential scanning calorimetry diagram of (x=5,10,15,20,25,30) alloys;

[0028] Figure 4 The unstretched cast Fe in Examples 1-12 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys;

[0029] Figure 5The cast Fe stretched by 10% in Examples 1-6 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys;

[0030] Figure 6 The cast Fe stretched by 20% in Examples 7-12 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys;

[0031] Figure 7 The unstretched annealed Fe 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys;

[0032] Figure 8 The annealed Fe stretched 10% in Example 13 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The present invention provides a method for improving the damping performance of an FeMn-based alloy, the method comprising: stretching the FeMn-based alloy. During the stretching process, stacking faults and twins are introduced into the FeMn-based alloy, and the stacking fault energy is changed and the phase transition free energy is increased by the stacking faults and twins, so that the phase transition from a close-packed hexagonal structure to a face-centered cubic structure requires higher energy to occur, thereby improving the damping applicable temperature range and damping performance of the FeMn alloy.

[0035] Optionally, the stretching formula (1) is

[0036] Y=a*b%; (1)

[0037] In one embodiment, Y is the stretched length, a is the length of the FeMn-based alloy before stretching, b is the stretching rate, and 1<b≤35. Within this range, first, the applicable damping temperature range of the alloy can be improved, second, the damping peak value will not be reduced, and third, the mechanical properties of the alloy will be affected to a great extent. Preferably, 1<b≤20. For example, b is 3, 7, 10, 15, 17. Here, as the stretching amount increases, the applicable damping temperature range moves to the high temperature zone, but the damping peak value will also decrease. If the stretching amount is further increased (b>35), although the applicable damping temperature will be increased, the damping peak value will also be reduced, which will further affect the mechanical properties of the alloy.

[0038] In one embodiment, the stretching is performed using a stretching machine. Here, during the stretching process, the stretching machine clamps both ends of the FeMn-based alloy, and at least one end is used for stretching, so that the stretching amount can be controlled and the stretching process is more uniform, so that the overall performance is more stable.

[0039] In one embodiment, the FeMn-based alloy is Fe 65-x Mn 20 Cr 15 Co x alloy; wherein x is 5-20. For example, x is 6, 9, 12, 15, 17, 19. Preferably, x is 5, 10, 15, 20. Here, the contents of Fe, Mn, and Co in the FeMn-based alloy are adjustable, so that the FeMn-based alloy is more widely used.

[0040] In one embodiment, the FeMn-based alloy is at least one of a cast alloy, an annealed alloy, and a nitrided alloy. Here, FeMn-based alloys in different states can be applied to different application scenarios to meet the needs of different industrial fields.

[0041] Here, the FeMn-based alloy can be prepared by vacuum non-consumable arc melting. Further, after the FeMn-based alloy is vacuum non-consumable arc melting, it can be polished with sandpaper, cleaned with ultrasonic waves, and dried.

[0042] Here, the sandpaper may be 80 mesh. Ethanol may be used for ultrasonic cleaning. The cleaning time may be 5-15 minutes. The drying treatment may be performed by heating. The heating time may be 15-30 minutes. The heating temperature may be 120-200°C. For example, the heating time may be 20, 25, or 29 minutes. The heating temperature may be 150°C, 170°C, or 190°C.

[0043] The present invention also provides a FeMn-based alloy, which is prepared by the above method for improving the damping performance of the FeMn-based alloy. The FeMn-based alloy damping is applied at a temperature of room temperature to 300° C., and the damping value is greater than or equal to 0.015.

[0044] The present invention improves the damping performance of the FeMn-based alloy by stretching, overcomes the problem of the use temperature being limited to 200°C in the prior art, and can increase the temperature to 300°C, thereby expanding the use temperature range and being applicable in more scenarios. At the same time, compared with the prior art, in which the alloy with a damping value greater than 0.01 is a high damping performance alloy, the present invention also increases the damping value to greater than or equal to 0.015, thereby having better performance and a wider range of application scenarios.

[0045] The present invention is described in detail below by way of examples and experimental examples, but these are merely examples and do not limit the present invention in any form.

[0046] Embodiment 1:

[0047] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 35 Mn 20 Cr 15 Co 30 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0048] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 10%. The stretching value calculation formula is: 40mm*10%, where 40mm is the original length of the sample without stretching, and 10% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 250℃ to around 275℃, and the damping applicable temperature range of the alloy is extended from 225℃-275℃ to 200℃-350℃, and the damping peak of the alloy is greater than 0.05 FeMn-based alloy.

[0049] Embodiment 2:

[0050] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 40 Mn 20 Cr 15 Co 25 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0051] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 10%. The stretching value calculation formula is: 40mm*10%, where 40mm is the original length of the sample without stretching, and 10% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 240℃ to around 260℃, and the damping applicable temperature range of the alloy is extended from 210℃-270℃ to 200℃-325℃, and the damping peak of the alloy is greater than 0.05 FeMn-based alloy.

[0052] Embodiment 3:

[0053] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 45 Mn 20 Cr 15 Co 20 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0054] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 10%. The stretching value calculation formula is: 40mm*10%, where 40mm is the original length of the sample without stretching, and 10% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 240℃ to around 260℃, and the damping applicable temperature range of the alloy is extended from 210℃-260℃ to 200℃-310℃, and the damping peak of the alloy is greater than 0.05 FeMn-based alloy.

[0055] Embodiment 4:

[0056] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 50 Mn 20 Cr 15 Co 15 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0057] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 10%. The stretching value calculation formula is: 40mm*10%, where 40mm is the original length of the sample without stretching, and 10% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 210℃ to around 240℃, and the damping applicable temperature range of the alloy is extended from 190℃-230℃ to 175℃-300℃, and the damping peak of the alloy is greater than 0.05 FeMn-based alloy.

[0058] Embodiment 5:

[0059] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 55 Mn 20 Cr 15 Co 10 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0060] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 10%. The stretching value calculation formula is: 40mm*10%, where 40mm is the original length of the sample without stretching, and b is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 200℃ to around 210℃, and the damping applicable temperature range of the alloy is extended from 175℃-225℃ to 150℃-275℃, and the damping peak of the alloy is greater than 0.05 FeMn-based alloy.

[0061] Embodiment 6:

[0062] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 60 Mn 20 Cr 15 Co5 FeMn-based alloy ingot. Use 80-mesh sandpaper to polish the oxide layer on the surface of the ingot. Put the ingot into ethanol for ultrasonic cleaning for 10 minutes, and then dry it in a vacuum drying oven at 200℃×30 minutes. Use wire cutting to cut the ingot into samples with specifications of 40*6*2mm.

[0063] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 10%. The stretching value calculation formula is: 40mm*10%, where 40mm is the original length of the sample without stretching, and 10% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 190℃ to around 200℃, and the damping applicable temperature range of the alloy is extended from 160℃-210℃ to 150℃-250℃, and the damping peak of the alloy is greater than 0.05 FeMn-based alloy.

[0064] Embodiment 7:

[0065] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 35 Mn 20 Cr 15 Co 30 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0066] Stretching treatment: clamp both ends of the sample and use a stretching machine to stretch the alloy by 20%. The stretching value calculation formula is: 40mm*20%, where 40mm is the original length of the sample without stretching, and 20% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 250℃ to around 280℃, and the damping applicable temperature range of the alloy is extended from 225℃-275℃ to 200℃-350℃. A new damping peak appears at 100℃-125℃, and the damping peak of the alloy is greater than 0.05 of FeMn-based alloys.

[0067] Embodiment 8:

[0068] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 40 Mn 20 Cr 15 Co 25 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0069] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 20%. The stretching value calculation formula is: 40mm*20%, where 40mm is the original length of the sample without stretching, and 20% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 240℃ to around 260℃, and the damping applicable temperature range of the alloy is extended from 210℃-270℃ to 200℃-350℃. A new damping peak appears at 100℃-125℃, and the damping peak of the alloy is greater than 0.05 of FeMn-based alloys.

[0070] Embodiment 9:

[0071] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 45 Mn 20 Cr 15 Co 20 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0072] Stretching treatment: clamp both ends of the sample and use a stretching machine to stretch the alloy by 20%. The stretching value calculation formula is: 40mm*20%, where 40mm is the original length of the sample without stretching, and 20% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 240℃ to around 260℃, and the damping applicable temperature range of the alloy is extended from 210℃-260℃ to 175℃-350℃. A new damping peak appears at 100℃-125℃, and the damping peak of the alloy is greater than 0.05 of FeMn-based alloy.

[0073] Embodiment 10:

[0074] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 50 Mn 20 Cr 15 Co 15 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0075] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 20%. The stretching value calculation formula is: 40mm*20%, where 40mm is the original length of the sample without stretching, and 20% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 210℃ to around 240℃, and the damping applicable temperature range of the alloy is extended from 190℃-230℃ to 150℃-350℃. A new damping peak appears at 100℃-125℃, and the damping peak of the alloy is greater than 0.05 of FeMn-based alloy.

[0076] Embodiment 11:

[0077] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 55 Mn 20 Cr 15 Co 10 FeMn-based alloy ingots were cast. The oxide layer on the surface of the ingots was polished with 80-mesh sandpaper. The ingots were ultrasonically cleaned in ethanol for 10 minutes and then dried in a vacuum drying oven at 200°C for 30 minutes. The ingots were cut into samples with a size of 40*6*2 mm using wire cutting.

[0078] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 20%. The stretching value calculation formula is: 40mm*20%, where 40mm is the original length of the sample without stretching, and 20% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 200℃ to around 225℃, and the damping applicable temperature range of the alloy is extended from 175℃-225℃ to 150℃-350℃. A new damping peak appears at 100℃-125℃, and the damping peak of the alloy is greater than 0.05 of FeMn-based alloy.

[0079] Embodiment 12:

[0080] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 60 Mn 20 Cr 15 Co5 FeMn-based alloy ingot. Use 80-mesh sandpaper to polish the oxide layer on the surface of the ingot. Put the ingot into ethanol for ultrasonic cleaning for 10 minutes, and then dry it in a vacuum drying oven at 200℃×30 minutes. Use wire cutting to cut the ingot into samples with specifications of 40*6*2mm.

[0081] Stretching treatment: clamp the two ends of the sample and use a stretching machine to stretch the alloy by 20%. The stretching value calculation formula is: 40mm*20%, where 40mm is the original length of the sample without stretching, and 20% is the stretching rate. Finally, the temperature corresponding to the damping peak is increased from around 190℃ to around 225℃, and the damping applicable temperature range of the alloy is extended from 160℃-210℃ to 150℃-350℃. A new damping peak appears at 100℃-125℃, and the damping peak of the alloy is greater than 0.05 of FeMn-based alloy.

[0082] Embodiment 13:

[0083] Sample preparation: The atomic ratio of Fe was prepared by vacuum non-consumable arc melting. 65-x Mn 20 Cr 15 Co x FeMn-based alloy ingots with (x=10, 20, 25, 30). Use 80-grit sandpaper to polish the oxide layer on the surface of the ingot. The ingot is ultrasonically cleaned in ethanol for 10 minutes, and then dried in a vacuum drying oven at 200℃×30min. The ingot is placed in an alumina crucible and then placed in a vacuum tube furnace. Use argon to wash the furnace for 10 minutes, and keep the argon input during the heating and insulation process. Heat to 1000℃ at a heating rate of 10K / min and keep it for 24h, then take out the ingot and water cool it. The alloy after solution treatment is rolled several times in the thickness direction to reduce its thickness by 50% to obtain a cold-rolled alloy. The cold-rolled alloy is dried in a vacuum drying oven at 250℃×40min. The cold-rolled alloy is placed in a vacuum tube furnace and heated to 1000℃ and kept for 5min, then taken out and water-cooled to obtain a recrystallization annealed alloy. The alloy after recrystallization annealing was placed in a vacuum tube furnace and heated to 700°C for 5 hours, then taken out and water-cooled. The ingot was cut into samples with specifications of 40*6*2mm by wire cutting.

[0084] Stretching treatment: Clamp the two ends of the sample and use a stretching machine to stretch the alloy by 10%. The stretching value calculation formula is: 40mm*10%, where 40mm is the original length of the sample without stretching, and 10% is the stretching rate. Finally, the temperature corresponding to the damping peak value x=10 increases from about 200℃ to about 210℃, x=15 increases from about 240℃ to about 250℃, x=25 increases from about 250℃ to 260℃, and x=30 increases from about 260℃ to 280℃. ℃, the damping applicable temperature range of the alloy is extended from 175℃-225℃ to 150℃-275℃ for x=10, from 200℃-260℃ to 200℃-350℃ for x=15, from 210℃-280℃ to 225℃-350℃ for x=20, and from 240℃-300℃ to 240℃-350℃ for x=30, and a new damping peak appears at 100℃-125℃, and the damping peak value of the alloy is greater than 0.05 of FeMn-based alloys.

[0085] Performance Test:

[0086] The FeMn-based alloy used in Examples 1-13 of the present invention was tested for crystal structure using an X-ray diffractometer. The sample size was 10mm×10mm×4mm, the sample surface was polished flat with 400-mesh sandpaper, and the angle scanning range was 5°-110°. The damping test was performed using a dynamic thermomechanical analyzer TA-Q800. The sample size was 36mm×6mm×1mm, and the sample surface was polished flat with 80-mesh sandpaper. The temperature scanning range was 25°C-390°C, and the test mode was single cantilever.

[0087] Figure 1 The unstretched cast Fe in Examples 1-12 of the present invention 65-x Mn 20 Cr 15 Co x X-ray diffraction patterns of (x=5,10,15,20,25,30) alloys; Figure 2 The unstretched annealed Fe 65-x Mn 20 Cr 15 Co x X-ray diffraction patterns of (x=5,10,15,20,25,30) alloys; Figure 3 The unstretched cast Fe in Examples 1-12 of the present invention 65- x Mn 20 Cr 15 Co x Differential scanning calorimetry diagram of (x=5,10,15,20,25,30) alloys; Figure 4The unstretched cast Fe in Examples 1-12 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys; Figure 5 The cast Fe stretched by 10% in Examples 1-6 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys; Figure 6 The cast Fe stretched by 20% in Examples 7-12 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys; Figure 7 The unstretched annealed Fe 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys; Figure 8 The annealed Fe stretched 10% in Example 13 of the present invention 65-x Mn 20 Cr 15 Co x Damping diagram of (x=5,10,15,20,25,30) alloys.

[0088] from Figure 1-8 It can be seen that the crystal structure of all unstretched alloys is HCP+FCC dual-phase structure, and the HCP structure is dominant. All unstretched alloys have phase transition peaks around 200℃.

[0089] from Figure 1-8 It can be seen that:

[0090] (1) The temperature range corresponding to the damping peak of the unstretched alloy is narrow and mainly located near 200°C, and the damping peak is relatively sharp and concentrated, indicating that the applicable range of temperature damping of the alloy is narrow and the temperature damping life is short. After the strain is introduced by stretching, the damping performance of the FeMn-based alloys used in all embodiments can be improved.

[0091] (2) Compared with the unstretched alloys, the temperature range of the damping peaks of all alloys moved toward the high temperature range after the introduction of 10% strain and 20% strain, and the damping peaks changed from sharp to diffuse, indicating that the applicable range of the temperature damping of the alloys was expanded and the temperature damping life was improved.

[0092] (3) Compared with the unstretched alloy, the damping peak values ​​of all alloys decreased after 10% and 20% stretching, but were all greater than 0.05, indicating that all alloys maintained high damping properties after the introduction of strain.

[0093] (4) The introduction of 10% strain in the present invention can not only expand the applicable range of temperature damping of the alloy and improve the temperature damping life, but also keep the damping peak at a high level. At the same time, the improvement effect brought about is better than the improvement effect brought about by 20% strain.

[0094] (5) The strain introduced by the present invention will cause the FeMn-based alloy used in Examples 1-13 to have a new damping peak at 100°C-150°C, thereby enhancing the overall damping performance.

[0095] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for improving the damping performance of FeMn-based alloys, characterized in that: The method comprises: The FeMn-based alloy is stretched; wherein, during the stretching process, stacking faults and twins are introduced into the FeMn-based alloy.

2. The method according to claim 1, characterized in that The stacking faults and twins introduced into the FeMn-based alloy hinder the transformation of the close-packed hexagonal structure in the FeMn-based alloy into a face-centered cubic structure.

3. The method according to claim 1 or 2, characterized in that: The stretching formula (1) is: Y = a*b% (1); Wherein, Y is the stretched length, a is the length of the FeMn-based alloy before stretching, b is the stretching rate, and 1<b≤35.

4. The method according to claim 3, characterized in that 1＜b≤20。 5. The method according to claim 1, characterized in that The stretching is performed using a stretching machine.

6. The method according to claim 5, characterized in that During the stretching process, the stretching machine clamps both ends of the FeMn-based alloy, and at least one end is used for stretching.

7. The method according to claim 1, characterized in that The FeMn-based alloy is Fe 65-x Mn 20 Cr 15 Co x Alloy; wherein x is 5-30.

8. The method according to claim 7, characterized in that The x is 5, 10, 15, 20, 25, or 30.

9. The method according to claim 1, characterized in that: The FeMn-based alloy is at least one of a cast alloy, an annealed alloy, and a nitrided alloy.

10. A FeMn-based alloy, characterized in that: The FeMn-based alloy is prepared by the method for improving the damping performance of the FeMn-based alloy according to any one of claims 1 to 9. The FeMn-based alloy damping is applied at a temperature of room temperature to 300° C., and the damping value is greater than or equal to 0.015.

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