31results about How to "Does not compromise structural integrity" patented technology

The invention relates to the technical field of metal-based composite materials, and specifically discloses a boron-doped graphene-reinforced copper-based composite material and a preparation method thereof. The copper-based composite material of the present invention uses boron-doped graphene as a reinforcing body, effectively increases the bonding interface between copper and graphene, and improves the electron transmission at the interface. Among them, boron-doped graphene is boron-doped on the complete graphene sheet, which basically does not destroy the structural integrity of graphene. The electron transport performance of graphene after boron doping is better, and Cu-B-C bonds can be formed between graphene and copper substrate, taking into account interface bonding and electron transport. The invention combines graphene doping, copper raw material and reinforcement mixing, heat treatment and other processes to successfully prepare a copper-based composite material with uniform distribution of boron-doped graphene. Experiments have proved that the tensile strength of the boron-doped graphene-reinforced copper matrix composite is not lower than 308.6 MPa, and the electrical conductivity is not lower than 90.6% IACS.

A transformer digital protection device and method based on full pressure information, including: a transient oil pressure characteristic quantity measurement module, a switch input module, a signal conditioning and acquisition module, and a digital core module; wherein, the transient oil pressure characteristic quantity measurement The module is connected with the signal conditioning and acquisition module, and the signal conditioning and acquisition module and the digital input module are all connected with the digital core module. The invention obtains the digital information of transient oil pressure at multiple measuring points inside the oil tank in real time, calculates and obtains the full value of the operating pressure representing the amplitude of the oil pressure, and utilizes the significant difference of the characteristic value under different operating conditions of the transformer to construct the protection criterion and the threshold value The setting method realizes reliable, rapid and sensitive screening and removal of internal faults in the transformer oil tank, and is not affected by the excitation inrush current. The principle of the invention is simple, the device is easy to implement, and it is suitable for the current and future requirements of large-capacity and high-voltage power transformers for non-electrical protection "four properties".

The invention provides a sheet-shaped acoustic black hole energy harvester group device, comprising a plurality of acoustic black hole energy harvesters and a lower bottom sealing plate of the energy harvester group, and a plurality of acoustic black hole energy harvesters are sequentially bonded and connected; a plurality of acoustic black hole energy harvesters The black hole energy harvester is firmly connected with the lower bottom sealing plate of the energy harvester group. The invention can adjust many parameters, has good vibration reduction effect, is suitable for solving the problem of low-frequency vibration, covers a wide frequency range, and overcomes the shortcomings of low structural strength and weak bearing capacity of the traditional acoustic black hole. In the application of vibration reduction, multiple energy harvester group devices can be arranged in a tiled manner, and acoustic black hole energy harvesters with different structural size parameters can be combined arbitrarily. On the basis of not destroying the integrity of the structure and reducing the safety of the structure, the "swallowing and capturing" function of vibrating in the specified frequency band has been realized. The invention can realize designable control of low-frequency, medium-frequency and high-frequency vibrations. The additional mass of the acoustic black hole energy harvester is small, the realization method is simple and flexible, and the energy absorption efficiency can be adjusted in any combination.