42results about How to "High voltage strength" patented technology

The invention discloses a CuCr40 electric contact prepared by adopting a vacuum melting casting method, which belongs to the technical field of metal material preparation. Its composition by weight percentage is: 40% Cr, and the rest is Cu. It is prepared by the following method: under the protection of low-temperature liquid, the Cr block is processed into Cr powder by grinding and crushing machine, the Cr powder is pressed and sintered into Cr powder, and then the Cu block and Cr powder are put into a vacuum furnace Heating, casting after melting, and then producing CuCr40 electrical contact material after cooling. The invention has the advantages of crushing Cr lumps into Cr powder, and then pressing and sintering to make Cr powder billets, which lowers the melting temperature and shortens the melting time. The preparation method of the invention has simple process and low cost, and the prepared CuCr40 composite material has superior performance compared with the infiltrated CuCr40 composite material.

The present application relates to a reliability testing method, device and system for GaN devices. The reliability testing method obtains the instantaneous current curve of the GaN device; wherein, the instantaneous current curve is obtained by applying a pulse signal to the GaN device; the pulse signal is a signal with a pulse width less than or equal to 1 microsecond. Based on the analysis of the instantaneous current curve, the reliability analysis results of the GaN device are obtained. A pulse signal with a small pulse width can apply short pulse electrical stress to the GaN device, and the gate region of the GaN device can apply a large transient cumulative voltage stress; at the same time, real-time monitoring and analysis of the current of the GaN device after each short pulse electrical stress Waveforms can obtain the dynamic whole-process behavior of device degradation and failure. The test method of the embodiment of the present application is simple and easy to operate. Under the condition of short pulse, a higher voltage intensity than the traditional test method can be applied, and the reliability of the device can be analyzed, and the advantages and disadvantages of different device structural parameters can be compared. .

The invention discloses a method for preparing CuWCr composite material in a consumable electrode arc smelting furnace. First, Cu powder, W powder and Cr powder are mixed in a mixer according to the mass percentage, and then the mixed powder is molded or cold isostatic pressing; then place the pressed billet in a vacuum sintering furnace, and raise the temperature to 950°C to 1050°C for sintering in a vacuum environment with a vacuum degree greater than 10-2Pa to obtain a CuWCr sintered billet. Finally, the CuWCr sintered blank is placed in a vacuum consumable electrode arc melting furnace, and melted in a vacuum environment, so that the CuWCr blank is melted and dropped into a water-cooled copper crucible under the high temperature of the arc, and taken out after cooling to obtain a CuWCr composite material. . The invention combines smelting and directional solidification to prepare a CuWCr composite material with excellent comprehensive properties such as uniform and fine structure, high voltage resistance strength, high density, low gas content, and less impurities.

The invention discloses a solid bus slot with high strength which consists of a shell made of the composite materials, the composition of the composite materials and a preparation method thereof. By adopting the bus slot, as the shell of the bus slot made of the composite materials, the bus slot has good hydrolytic resistance and good anti-salt fog performance. The withstand voltage is as high as5000V or more; and as the linear expansion coefficient of the composite materials are very close to the conductor, the situation of 'extended bite' with each other can not appear due to the mixed-assembled with a plurality of materials with different expansion coefficients, thus improving the insulation protection of the bus slot and having very high insulation performance. The mechanical strengthof the bus slot made of the composite materials is high, which can withstand 15 Joules impact strength. The overload capability of the bus slot is strong, the anti inter-phase short circuit ability is good, the low temperature resistance is good, the protection grade can achieve IP68, and the use life is longer than that of the metal.

The present invention discloses a lead-free glass frit for the dielectric layer of a plasma display, and the glass frit comprises the following raw materials according to the weight percentage: 30%-50% of Bi2O3, 5%-40% of B2O3, 5%-30% of BaO, 0.1%-10% of Al2O3, 0.1%-10% of ZnO, 0.1%-10% of MgO and0.1%-5% of La2O3. The invention has the advantages that the glass frit belongs to environment-friendly materials; various performances are excellent; the cost performance is high; the glass frit has suitably and easily adjusted thermal expansion coefficient and proper sintering temperature, and also has good chemical stability and high dielectric strength; the competitive power is very strong in lead-free performance and cost performance; and the glass frit has wide market development prospect.

The invention discloses a preparation method of a copper-tungsten alloy. After mixing submicron tungsten powder, micron tungsten powder, supermicron tungsten powder and induced Cu powder, they are bonded, dried and sieved to obtain a mixed Powder; the mixed powder is pre-pressed to form a blank, and then the blank is sintered and infiltrated. The CuW alloy and CrCu material prepared above were placed in a high-purity graphite crucible for sintering under a hydrogen protective atmosphere, and then solid solution aging treatment was performed to obtain a CuW-CrCu monolithic material. The present invention prepares CuW alloys with multi-particle sizes by adding different contents of sub-micron and ultra-micron tungsten powders to conventional micron-sized tungsten powders, and the electrical conductivity of the prepared alloys is significantly improved, which is 30% to 50% higher than the national standard . The arc erosion resistance of the CuW alloy prepared under this scheme is enhanced, and its withstand voltage strength is improved; the bonding strength of the prepared CuW‑CrCu monolithic material is significantly improved.

The invention discloses an integrated multi-stage high-voltage pulse isolation inductor. The integrated multi-stage high-voltage pulse isolation inductor comprises a plurality of insulating connecting sections connected in sequence, a copper ring electrode is clamped between every two adjacent insulating connecting sections, each copper ring electrode is coaxially sleeved with a tubular voltage-sharing electrode, and each voltage-sharing electrode and the corresponding copper ring electrode are connected into a whole through bolts. The integrated multi-stage high-voltage pulse isolation inductor further comprises a wire, and the wire is evenly and spirally wound on the outer surface of the insulating connecting sections connected into a whole and is connected with each copper ring electrode in a pressing mode through bolts. The integrated multi-stage high-voltage pulse isolation inductor is higher in voltage resistance strength, small in contact resistance and compact in structure.

A high-voltage capacitor with a rectifying device comprises a casing (1) and two soldering terminals (3). A cover (2) is arranged at the opening end of the casing (1), a capacitor core (9) is arranged in the inner cavity of the casing (1), two electrodes of the capacitor core (9) are respectively soldered with one end of each soldering terminal (3) together, a resistor (7) is arranged between thetwo electrodes, the other ends of the soldering terminals (3) extend outside the cover (2), a silicon pad (5) is arranged between each soldering terminal (3) and the cover (2), and an insulating stool (4) is arranged around the end of each soldering terminal (3) extending outside the cover (2). The high-voltage capacitor also comprises a diode (8) which is arranged inside the inner cavity of the casing (1) and has one end thereof connected with the capacitor core (9) and the other end thereof connected with the cover (2), and insulating paper boards (6) are arranged between the diode (8) and the casing (1), between the diode (8) and the cover (2) and between the diode (8) and each soldering terminal (3). Compared with the prior art, the high-voltage capacitor is characterized by high withstand voltage strength of the diode, and long service life.

The invention relates to the field of electronic ceramics and provides a PTCR ceramic material and a preparation method and application thereof. The PTCR ceramic material has a general formula x(BaTiO3)-y(SrTiO3)-(1-x-y)(CaTiO3)+a mol% M+b mol% N, x is greater than or equal to 0.6 and less than or equal to 0.9, y is greater than or equal to 0.1 and less than or equal to 0.4, a is greater than or equal to 0.1 and less than or equal to 1, b is greater than or equal to 0 and less than or equal to 3, the sum of x and y is less than or equal to 1, M represents any one or more of Y2O3, Bi2O3, La2O3, Sm2O3, Nb2O5, Ta2O5 and Sb2O5, and N represents any one or more of MnO2, CuO, Fe2O3, ZrO2, Al2O3, SiO2, TiO2, BN and B2O3. The PTCR ceramic material has the advantages of low Curie temperature, high resistance abrupt change ratio and high resistance temperature coefficient.