32results about How to "Strong ablation resistance" patented technology

The invention provides a dual-rotational-flow inspirator, which comprises a top cover, a nozzle, an upper bottom, a middle bottom, a gas whirlcone and an inspirator cavity, wherein the inspirator cavity is a barrel-shaped hollow cylinder; a fuel cavity is formed between the top cover and the upper bottom of the inspirator; a gas oxidizing agent cavity is formed between the upper bottom and the middle bottom of the inspirator; a water cavity is formed between the middle bottom of the inspirator and the base of the inspirator; an inner nozzle passes through mounting holes in the upper bottom, the middle bottom and the inspirator cavity and is fixedly arranged on the upper bottom via a thread; the gas whirlcone is installed on the nozzle by a thread; water nozzles are water holes evenly distributed on the circumstance on the base of the inspirator. The inspirator provided by the invention has the characteristics of simple structure, low cost, good atomization performance and stable flame.

The invention relates to a preparation method of a multi-element composite reinforced molybdenum alloy. The preparation method sequentially comprises the following steps that the Mo source, the Ti source, the Zr source, the C source, the Hf source and the Re source are weighed according to a certain weight ratio, the raw materials are prepared and mixed to obtain the uniform molybdenum alloy powder; the molybdenum alloy powder is placed in a mold cavity of a mold and is subjected to compression forming treatment to obtain a forming blank; high-temperature sintering treatment on the formed blank is carried out under vacuum to obtain a sintered blank; forging or rolling deformation processing is carried out on the sintered blank to obtain a forged blank or a rolled blank; and annealing heattreatment on the forged blank or the rolled blank is carried out to obtain the molybdenum alloy plate or a rod material. According to the preparation method, the steps and the process conditions are reasonable in design and good in using effect, the prepared molybdenum alloy material has excellent performance, the tensile strength Ra is greater than or equal to 200 MPa at a high temperature of 1600 DEG C, the percentage elongation after fracture is larger than or equal to 20%, and the oxygen content is less than or equal to 100 ppm.

The invention belongs to the field of high-power pulses, and in particular relates to a closed planar three-electrode spark switch and a preparation method thereof. It includes the bottom PCB board, the circuit layer, the PP layer and the top PCB board in turn. The bottom PCB board is the substrate of the switch circuit layer; the circuit layer includes the anode, the cathode and the trigger electrode and the pads connected to them; the PP layer corresponds to the position of the pad There is a window for the pad, and an electrode window is set at the position corresponding to the electrode; the top layer PCB is provided with a pad slot corresponding to the pad, and a blind slot is provided at the position corresponding to the electrode; the PP layer is used as the top PCB board and the bottom layer The dielectric layer bonded to the PCB board uses the PP layer to press the bottom PCB and the bottom PCB board to form a cavity inside the entire switch. The invention utilizes printed circuit board technology to make the plane three-electrode spark switch into a closed type, which stabilizes the working environment of the switch, improves the ability of the switch to withstand high overload, and greatly reduces the cost, and can be widely used in explosive foil detonators, Pulse power systems such as electric guns.

The invention relates to a remote high-voltage pulse nanosecond switch applying insulating oil. The remote high-voltage pulse nanosecond switch comprises an organic glass shell, an electrode disk, a cathode, an anode, a triggering electrode, an electromagnet, a refined rapeseed oil serving as an insulating medium and a remote triggering and controlling system. The cathode, the anode and the electrode disk are tightly fixed together through bolts; the head of an electromagnet shell is provided with a thread and is connected with the organic glass shell of the switch; the tail end of an electromagnet core is connected with the triggering electrode through an organic glass rod; and the remote triggering and controlling system consists of a wireless remote controller, a receiving antenna, a high-frequency receiving module packaged in a metallic shield shell, a decoding integrated circuit (IC), a driving circuit, a relay and a storage battery. According to the remote high-voltage pulse nanosecond switch, radio signals emitted from the controller are received by the antenna, transmitted to the high-frequency receiving module and decoded by the decoding IC, the relay is driven by the driving circuit to energize the electromagnet and push the triggering electrode to move towards a main electrode, so that quick high voltage discharging is safely, reliably and conveniently realized, anda pulse wave form of which the rising edge is a nanosecond level is formed.

A method for preparing a composite ceramic coating on the surface of a carbon / carbon composite material belongs to the field of aerospace technology, and the specific steps are: taking Si, SiC and MoSi according to the amount ratio of substances 2 Mix the powder, add the binder according to the ratio, and mix thoroughly to form a mixture; add deionized water to the mixture to make a viscous suspension, stir it again after standing still, and evenly coat the suspension on C / The surface of the C composite material forms a pre-coating; after air-intervention drying treatment, the surface is coated with SiC‑MoSi 2 Pre-coated carbon / carbon composite sample placed in a mold for calcination, SiC‑MoSi 2 The chemical reaction between the pre-coating layer and the carbon / carbon composite material substrate produces SiC~MoSi on the surface of the carbon / carbon composite material 2 Composite ceramic coating. The surface SiC~MoSi of the carbon / carbon composite material prepared by the invention 2 The composite ceramic coating is tested by scanning electron microscope and metallographic microscope to be closely combined with the substrate, and has good oxidation resistance and ablation resistance.

A hydrogen-oxygen igniter using electric glow plugs includes an oxygen chamber top cover, a head, a body, electric glow plugs and a hydrogen chamber top cover. The hydrogen chamber cover is set on the outside of the upper part of the body, and the head is welded on the top of the body. A hydrogen collection chamber is formed between the hydrogen chamber cover, the head and the body, and the cavity of the head is connected with the cavity of the body to form an ignition The inner cavity of the device; the hydrogen collection cavity communicates with the cooling jacket of the body through the throttle hole. The top cover of the oxygen chamber is welded on the head; an oxygen collection chamber is formed between the top cover of the oxygen chamber and the head, and a blind hole is processed on the top of the head, which communicates with the inner cavity of the igniter. injector. Two glow plugs are installed symmetrically on the head, and a hydrogen injection cavity, a hydrogen injector and two hydrogen flow channels are also processed in the head, each hydrogen flow channel is perpendicular to the axis of the glow plug hole, and is used to connect the hydrogen collection The hydrogen injection cavity in the cavity and the head, the hydrogen injection cavity communicates with the inner cavity of the igniter through the hydrogen injector. The invention improves the ignition reliability and expands the applicable field of the electric igniter.

The invention belongs to the technical field of anti-ablation protection of aluminum alloy, and particularly relates to an anti-ablation rubber composition used as an anti-ablation protective coatingin an aluminum alloy product, an aluminum alloy product and a preparation method of the aluminum alloy product. The invention provides an application of the anti-ablation rubber composition as the anti-ablation protective coating in the aluminum alloy product. The aluminum alloy product provided by the invention comprises a cylinder body and an anti-ablation protective coating adhered to the innersurface of the cylinder body, and the anti-ablation protective coating is primarily prepared from an anti-ablation rubber composition. The preparation method provided by the invention can be used todirectly cure modified silicone rubber material on the inner surface of a thin-wall aluminum alloy closing cylinder body; the thin-wall aluminum alloy closing cylinder body is protected from ablationunder the erosion of high-temperature high-pressure gas; and the method is particularly suitable for the anti-ablation protection of bullet shells and the inner surface of a small-caliber cartridge. The anti-ablation rubber composition provided by the invention has the characteristics of low cost, high safety factor and strong anti-ablation capability.

A preparation method of a SiC-ZrC segmented ceramic matrix composite spray pipe is characterized in that the ceramic matrix composite comprises a porous C / C composite framework, a SiC coating and a ZrC coating. A CVI (chemical vapor infiltration) method is adopted to prepare a porous C / C precast body which is placed into absolute ethyl alcohol for ultrasonic oscillation and cleaning and placed into a graphite crucible after drying; Si is placed on the surfaces of a straight section and a skirt part of the porous C / C precast body, the porous C / C precast body with Si is then embedded by SiC powder, and the porous C / C precast body embedded by the Sic powder is placed into a tube furnace and heated to a high temperature; Zr is placed at the skirt section of the porous C / C precast body, and the porous C / C precast body with Zr is then placed into the tube furnace and heated to the high temperature; a melt is infiltrated into the porous body through capillary force and reacts to obtain the SiC-ZrC segmented ceramic matrix composite spray pipe. Obtained ceramic matrix composite has the advantages of light weight, high strength, low porosity, high antioxidant and ablation-resistant capacities, short preparation period and low cost.

The invention discloses a magnetic plasma thruster provided with a conical porous hollow cathode and belongs to the electric propulsion field. The magnetic plasma thruster provided with the conical porous hollow cathode is of a cylindrical structure as a whole. The exterior of the magnetic plasma thruster provided with the conical porous hollow cathode sequentially comprises a middle connection piece, an anode connection piece and an anode from left to right. The anode connection piece is connected with the anode and the middle connection piece at the same time. The interior of the magnetic plasma thruster provided with the conical porous hollow cathode sequentially comprises a second cathode connection piece, a first cathode connection piece, an insulator and the cathode from left to right, and the second cathode connection piece, the first cathode connection piece, the insulator and the cathode are coaxially matched; the second cathode connection piece is provided with the first cathode connection piece in a matched manner in the radial direction; the insulator is arranged in the anode connection piece in a clamped and sleeved manner; the cathode is clamped to the insulator and the conical face of the first cathode connection piece; and the conical face of the cathode and the conical face of the first cathode connection piece are closely matched through a 5-degree conical angle. The magnetic plasma thruster provided with the conical porous hollow cathode has the beneficial effects that the cathode is wrapped in the cathode connection pieces, the second cathode connection piece tightly presses the tail portion of the cathode, it is guaranteed sufficient pressing force exists on the cathode, and the situation that the cathode becomes less crowded because of thermal expansion is prevented; and a porous structure is adopted for the head portion of the cathode, a larger current emitting area is achieved, and the current emitting capacity is improved.

The invention discloses a novel cavel combination gap. The novel cavel combination gap comprises an H-shaped steel base, a first base sliding block, a second base sliding block, a third base sliding block, a cavel gap combination, an adjustable supporting column, a metal plate and a metal plate supporting seat. The first base sliding block, the second base sliding block and the third base sliding block are respectively embedded in the H-shaped steel base, and can slide along the H-shaped steel base; a first supporting column insulator is carried by the first base sliding block; the second base sliding block is used for supporting a second supporting column insulator; the metal plate is fixed to the second supporting column insulator through the metal plate supporting seat; the third base sliding block is used for carrying the adjustable supporting column; the cavel gap combination comprises a first insulator supporting column, a first cavel electrode arranged on the first insulator supporting column, the adjustable supporting column and a second cavel electrode arranged on the adjustable supporting column. Due to the implement of the novel cavel combination gap, the metal plate is additionally arranged between the cavel electrodes, and accordingly gap thunder and lightning withstand voltages of the gap under the same gap length condition can be increased and the power-frequency breakdown voltages of the gap can be reduced.