NiTi shape memory alloy with functions of energy absorption and vibration reduction, and preparation method and application thereof

Abstract

The invention discloses a nickel-titanium shape memory alloy capable of simultaneously realizing the functions of energy absorption and vibration reduction, and a preparation method and application thereof, and relates to the technical field of NiTi shape memory alloys. A cold-deformed nickel-rich NiTi alloy is used for preparing a hand-shaped structure with a negative poisson ratio characteristic, and the phase change behavior and mechanical property of the NiTi alloy are regulated and controlled through heat treatment to a cold-deformed nickel-rich NiTi alloy component. Thus, stress-inducedmartensitic transformation occurs to the NiTi alloy component in the impact deformation process, and large impact energy is absorbed. The deformed NiTi alloy component is kept in a martensite state, and energy dissipation is promoted due to interaction between martensite variants, so that the component has higher damping performance after completion of impact, and a good damping effect is achieved.

Description

technical field

[0001] The invention belongs to the technical field of NiTi shape-memory alloys, and in particular relates to a NiTi shape-memory alloy with both energy-absorbing and vibration-reducing functions, and a preparation method and application thereof. Background technique

[0002] Collision energy-absorbing devices have broad application prospects in aerospace, transportation and other fields. At present, most energy-absorbing devices are made of aluminum alloy or steel, which undergoes plastic deformation during the collision process, and can convert the impact energy into plastic deformation energy of the material, thereby dissipating the impact energy and achieving the purpose of buffering and energy absorption. However, aluminum alloy or steel materials have lower damping properties. Although it can absorb most of the impact energy after plastic deformation, it cannot effectively suppress the vibration caused by the impact. High-frequency or low-frequency vi...

Examples

preparation example Construction

[0024] The present invention also provides a preparation method of the alloy, which includes the following steps: (1) annealing the cold deformed nickel-rich NiTi shape memory alloy, the annealing temperature ranges from 100°C to 700°C, and the annealing time ranges from 10 minutes to 200°C Hour;

[0025] (2) Adjust the phase transition temperature of the NiTi alloy by annealing to make the martensitic transformation start temperature (M s ) is lower than the working temperature, while the austenite transformation start temperature (A s ) higher than the operating temperature.

[0026] The cold deformed nickel-rich NiTi shape memory alloy selected in the present invention is preferably plate or wire, and its composition range is preferably 50.1 at.% to 51.5 at.% (atomic fraction) of Ni content, and the total deformation is 10% to 90%. , wherein the last pass cold deformation is 10% to 50%; more preferably Ni content is 50.8at.% to 51.0at.% (atomic fraction), the total deform...

Embodiment 1

[0034] A method for processing a NiTi alloy structure with both energy absorbing and vibration damping functions, comprising the steps of:

[0035] (1) Select a nickel-rich NiTi alloy plate with a total deformation of 70% and a final cold deformation of 25%, with a nickel content of 50.8 at.% (atomic fraction).

[0036] (2) Use the mold to shape the NiTi alloy plate through heat treatment, and control its phase transition temperature and mechanical properties at the same time. The setting temperature is 450°C, and the holding time is 1 hour. The phase transition temperature is as follows: Figure 5 shown. It should be pointed out that two phase transition peaks appear during the cooling process, and the first phase transition peak corresponds to the R-phase phase transition in NiTi alloy. Since the strain corresponding to R-phase transformation is less than 1%, it has little effect on the mechanical properties of NiTi alloy in practical application.

[0037] (3) After the a...

technical field

[0001] The invention belongs to the technical field of NiTi shape-memory alloys, and in particular relates to a NiTi shape-memory alloy with both energy-absorbing and vibration-reducing functions, and a preparation method and application thereof. Background technique

[0002] Collision energy-absorbing devices have broad application prospects in aerospace, transportation and other fields. At present, most energy-absorbing devices are made of aluminum alloy or steel, which undergoes plastic deformation during the collision process, and can convert the impact energy into plastic deformation energy of the material, thereby dissipating the impact energy and achieving the purpose of buffering and energy absorption. However, aluminum alloy or steel materials have lower damping properties. Although it can absorb most of the impact energy after plastic deformation, it cannot effectively suppress the vibration caused by the impact. High-frequency or low-frequency vi...

Examples

preparation example Construction

[0024] The present invention also provides a preparation method of the alloy, which includes the following steps: (1) annealing the cold deformed nickel-rich NiTi shape memory alloy, the annealing temperature ranges from 100°C to 700°C, and the annealing time ranges from 10 minutes to 200°C Hour;

[0025] (2) Adjust the phase transition temperature of the NiTi alloy by annealing to make the martensitic transformation start temperature (M s ) is lower than the working temperature, while the austenite transformation start temperature (A s ) higher than the operating temperature.

[0026] The cold deformed nickel-rich NiTi shape memory alloy selected in the present invention is preferably plate or wire, and its composition range is preferably 50.1 at.% to 51.5 at.% (atomic fraction) of Ni content, and the total deformation is 10% to 90%. , wherein the last pass cold deformation is 10% to 50%; more preferably Ni content is 50.8at.% to 51.0at.% (atomic fraction), the total deform...

Embodiment 1

[0034] A method for processing a NiTi alloy structure with both energy absorbing and vibration damping functions, comprising the steps of:

[0035] (1) Select a nickel-rich NiTi alloy plate with a total deformation of 70% and a final cold deformation of 25%, with a nickel content of 50.8 at.% (atomic fraction).

[0036] (2) Use the mold to shape the NiTi alloy plate through heat treatment, and control its phase transition temperature and mechanical properties at the same time. The setting temperature is 450°C, and the holding time is 1 hour. The phase transition temperature is as follows: Figure 5 shown. It should be pointed out that two phase transition peaks appear during the cooling process, and the first phase transition peak corresponds to the R-phase phase transition in NiTi alloy. Since the strain corresponding to R-phase transformation is less than 1%, it has little effect on the mechanical properties of NiTi alloy in practical application.

[0037] (3) After the a...

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