CN-121999747-A - Shape memory alloy phonon crystal sandwich unit and array sandwich structure

CN121999747ACN 121999747 ACN121999747 ACN 121999747ACN-121999747-A

Abstract

The invention discloses a shape memory alloy phonon crystal sandwich unit and an array sandwich structure, wherein the shape memory alloy phonon crystal sandwich unit comprises a crystal cavity formed by surrounding an upper substrate, a lower substrate and a rib plate, and shape memory alloy phonon crystals arranged in the crystal cavity, the shape memory alloy phonon crystals comprise a coating body, a scattering body and a plurality of Ni-Ti shape memory alloy particles, and the Ni-Ti shape memory alloy particles comprise three different transformation forms of austenitic Ni-Ti shape memory alloy, I-type martensitic Ni-Ti shape memory alloy and II-type martensitic Ni-Ti shape memory alloy. The shape memory alloy phononic crystal interlayer design can change the shape-regulating band gap and the sound insulation curve through temperature control, is beneficial to promoting the realization of temperature self-adaptive regulation performance, can widen the sound insulation frequency range of the interlayer structure, and effectively solves the problems of light broadband self-adaptive sound insulation and the like.

Inventors

HUANG QIBAI
FENG YIWEN
MAO ZHIWEN
ZHANG WENXUAN
ZHANG YU

Assignees

华中科技大学

Dates

Publication Date: 20260508
Application Date: 20260304

Claims (10)

1. The shape memory alloy phonon crystal interlayer unit is characterized by comprising an upper substrate, a lower substrate, a rib plate and a shape memory alloy phonon crystal; The rib plate is arranged between the upper substrate and the lower substrate, and is enclosed together with the upper substrate and the lower substrate to form a crystal cavity; the shape memory alloy phonon crystal comprises a cladding body, a scattering body and a plurality of Ni-Ti shape memory alloy particles, wherein the scattering body is arranged in the central area of a lower substrate at the bottom of a crystal cavity, and the plurality of shape memory alloy particles are uniformly distributed on a heat radiation body; The Ni-Ti shape memory alloy particles comprise three different transformation forms of austenite shape Ni-Ti shape memory alloy, I-type martensite shape Ni-Ti shape memory alloy and II-type martensite shape Ni-Ti shape memory alloy.
2. The shape memory alloy photonic crystal sandwich unit according to claim 1, wherein the shape memory alloy particles have a thickness of 1-3mm and a unit cell lattice constant of 12-20mm.
3. The shape memory alloy phononic crystal interlayer unit according to claim 1, wherein the shape memory alloy particles can be transformed into three different shapes according to temperature, and the Ni-Ti shape memory alloy exhibiting a type I martensitic shape when cooled to the transformation temperature, the Ni-Ti shape memory alloy exhibiting a type II martensitic shape, and the shape thereof, and the austenitic Ni-Ti shape memory alloy and the shape thereof are restored when heated to the reverse phase transformation temperature.
4. The shape memory alloy phononic crystal interlayer unit according to claim 1, wherein the three shapes comprise an austenitic shape, an elliptical hollow column-like structure with smooth and closed outer surfaces, an I-shaped martensitic shape, an L-shaped structure with lattice folded and sheared, with geometric opening features pointing towards the center of the structure, and an II-shaped martensitic shape, with lattice unfolded and sheared, with geometric opening features pointing outwards away from the center of the structure.
5. The shape memory alloy phononic crystal interlayer unit of claim 1, wherein the Ni-Ti shape memory alloy particles are trained using an incremental stress gradient thermo-mechanical training process, wherein stress and incubation times exhibit increasing regularity.
6. The shape memory alloy phononic crystal interlayer unit of claim 1, wherein the incremental stress gradient thermo-mechanical training process comprises the steps of: 1) Placing the Ni-Ti shape memory alloy material in a training device, and performing cold and hot circulation for 3-5 times in a full temperature zone without load, wherein the single circulation step comprises heating to the highest temperature for 8-10min, maintaining for 4-6min, cooling to the lowest temperature for 8-10min, and maintaining for 4-6min; 2) Applying a first-stage constant stress, wherein the stress is 30-40% of the yield stress of the alloy martensitic platform, and performing 10-15 times of heat-cold circulation under the low stress, wherein the single heat-cold circulation step is the same as the step 1); 3) The stress level is raised to the second level, and is set to be 60-70% of the yield stress of the alloy martensite, and the alloy martensite is continuously subjected to 15-20 times of heat and cold circulation under the moderate stress, wherein the single heat and cold circulation step is different from the step 1) only in that the holding time of the highest temperature is prolonged to 9-12min; 4) The stress level is raised to the third level, which is set to be 85-95% of the yield stress of the alloy martensite, the last 10-15 hot and cold cycles are carried out under the high stress, and the training is finished in a high-temperature austenite state, wherein the single hot and cold cycle step is only different from the step 1) in that the holding time of the highest temperature is prolonged to be 14-16min.
7. The shape memory alloy phononic crystal interlayer unit according to claim 1, wherein the Ni-Ti shape memory alloy is further provided with an elastic coating on the surface thereof on the basis of incremental stress gradient thermo-mechanical cycle training, and the elastic coating is made of a silicone rubber material with shore hardness of a 40-70.
8. The shape memory alloy phononic crystal interlayer unit according to claim 1, wherein the total number of the Ni-Ti shape memory alloy particles is more than 4, and the Ni-Ti shape memory alloy particles are symmetrically and uniformly arranged on the surfaces of the scatterer and the cladding body in a gluing way.
9. The shape memory alloy phononic crystal interlayer unit according to claim 1, characterized in that the Ni-Ti shape memory alloy material has a Ni content of 50-52at.%.
10. An array sandwich structure based on the shape memory alloy phonon crystal sandwich unit according to any one of claims 1-9 is characterized by comprising an upper substrate, a lower substrate, a plurality of rib plates and shape memory alloy phonon crystals arranged in an array, wherein the rib plates are arranged between the upper substrate and the lower substrate at uniform intervals along the transverse direction and the longitudinal direction of the lower substrate, the rib plates extending transversely are vertically crossed and fixed with the rib plates extending longitudinally, a plurality of crystal cavities distributed in an array are formed by surrounding the upper substrate and the lower substrate together, and a group of shape memory alloy phonon crystals are arranged in each crystal cavity.

Description

Shape memory alloy phonon crystal sandwich unit and array sandwich structure Technical Field The invention relates to the technical field of phonon crystal sandwich structures, in particular to a shape memory alloy phonon crystal sandwich unit, a structure and a preparation method thereof. Background Along with urgent demands of the fields of rail transit, aerospace and the like for lightweight sound insulation materials, the traditional sandwich structure (such as metal-honeycomb core-metal) faces the challenges of poor low-frequency sound insulation performance, limited adjustability, insufficient environmental adaptability and the like. The phonon crystal can inhibit the sound wave propagation of a specific frequency band in a targeted manner due to the band gap characteristic, but the existing phonon crystal still has some defects, such as fixed band gap frequency of a traditional structure (such as a periodic scatterer embedded into a polymer matrix) and incapability of dynamically adapting to noise spectrum change, and the lightweight design often sacrifices the bearing capacity of the structure, so that sound insulation failure is caused under vibration coupling and the like. The super-elastic effect and the temperature-driven phase change characteristic of the Shape Memory Alloy (SMA) provide a new thought for solving the problems, and the band gap frequency of the phonon crystal can be adaptively adjusted in real time through the phase change temperature of the SMA. Patent application CN118898980A and patent CN114623179A both disclose a phonon crystal sandwich structure, which solves the problems of vibration reduction, sound insulation and the like in the corresponding fields. According to the scheme, although the sandwich plate structure is introduced into the phonon crystal, the structure is not adjustable, the sound insulation performance is not adjustable, complex working conditions cannot be met, and the temperature self-adaptive adjusting performance cannot be realized. Further research and design of a novel light broadband self-adaptive noise control structure to cope with complex working environments is a key problem which needs to be solved urgently in the field at present. Disclosure of Invention The invention mainly aims to provide a shape memory alloy phonon crystal sandwich structure, aiming at the problems and the defects existing in the prior shape memory alloy phonon crystal sandwich plate for sound insulation. In order to achieve the above purpose, the invention adopts the following technical scheme: comprises an upper substrate, a lower substrate, surrounding rib plates and shape memory alloy phonon crystals; The rib plate is arranged between the upper substrate and the lower substrate, and is enclosed together with the upper substrate and the lower substrate to form a crystal cavity; the shape memory alloy phonon crystal comprises a cladding body, a scattering body and a plurality of Ni-Ti shape memory alloy particles, wherein the scattering body is arranged in the central area of a lower substrate at the bottom of a crystal cavity, and the plurality of shape memory alloy particles are uniformly distributed on a heat radiation body; The Ni-Ti shape memory alloy particles comprise three different transformation forms of austenite shape Ni-Ti shape memory alloy, I-type martensite shape Ni-Ti shape memory alloy and II-type martensite shape Ni-Ti shape memory alloy. As a preferable embodiment of the present invention, the scatterer is made of a metal material such as lead, aluminum alloy, or steel. Further, the diffuser is embedded in the center of the cover. Further, the thickness of the scatterer is the same as the thickness of the clad. As a preferable embodiment of the present invention, the coating body is made of nitrile rubber, silicone rubber, neoprene rubber, or the like. Further, the thickness of the shape memory alloy particles is 1-3mm, and the unit cell lattice constant is 12-20mm. Further, the shape memory alloy particles are symmetrically distributed along the phonon crystal axis in the shape memory alloy phonon crystal. Further, the shape memory alloy particles may change three different shapes according to temperature changes. Further, the three shapes comprise an austenite (basic austenite configuration), an alloy particle with an elliptical hollow elliptic cylinder structure with a smooth outer surface and a closed (no opening), a high-temperature high-symmetry phase corresponding to the alloy, an I-type martensite (self-cooperation martensite configuration), an L-shaped structure formed by folding and shearing the alloy particle in a lattice, wherein the geometric opening characteristic of the L-shaped structure points to the center of the structure, and an II-type martensite, which shows an L-shaped structure formed by unfolding and shearing the lattice, and the geometric opening characteristic of the L-shaped structure points to the outer side away from the cen