114results about How to "Low mechanical sensitivity" patented technology

The invention discloses thermit and a preparation method thereof. The thermit comprises, by weight, 20-30 parts of Al powder, 70-80 parts of manganese dioxide and 5-10 parts of additives. The additives comprise one or combination of more of magnesium powder, nickel powder, nitrate barium and polytetrafluoroethene. The preparation method includes a series of steps of drying and dry-blending components and making grain and the like. The thermit is good in thermal stability, low in mechanical sensitivity and sensitivity of rifle bullet impact, good in integral security, high in ignition reliability, stable in burning process and appropriate in burning speed. Heat released by burning and produced high-temperature slag are concentrated in flame jet flow, and only a small amount of liquid slag is produced.

The invention provides a preparation method for reducing mechanical sensitivity of HMX. The preparation method comprises the following steps of: preparing an alkali solution with a pH value being 8-11; dissolving catechol substances into the alkali solution to obtain a catechol alkali solution with concentration being 0.1g / L-20g / L, wherein the pH value of the completely dissolved solution is greater than 7; putting HMX into the catechol alkali solution and stirring for 0.1-24 hours to obtain a mixed dispersion liquid; carrying out suction filtration cleaning on the mixed dispersion liquid treated in the step III, and cleaning the mixed dispersion liquid by distilled water; drying the mixed dispersion liquid for 1-24 hours at a temperature of 50-80 DEG C to obtain an modified HMX material. The preparation method is simple in process, and physical characteristics such as crystal shape, density and the like of the HMX are not changed; and the modified HMX material has relatively low mechanical sensitivity, so that the friction sensitivity can be reduced by 30%, characteristic height is improved by more than one time, and therefore, the HMX has relatively high safety performance.

The invention relates to a desensitizing agent for reducing mechanical sensitivity of a pyrotechnic mixture. The desensitizing agent is prepared by mixing and stirring 92%-98% of dimethicone and 2%-8% of op-10 alkylphenol polyoxyethylene. Containing surface active substances, the desensitizing agent for reducing mechanical sensitivity of a pyrotechnic mixture can penetrate into mixture gaps afterbeing added into a pyrotechnic mixture. The agent not only plays a role in heat absorption and heat insulation, but also has buffering and lubricating effects, and can reduce friction as well as stress concentration phenomena among pyrotechnic mixture crystal grains, thus reducing the probability hot spot generation and effectively preventing mixture hot spot formation and expansion caused by friction. Besides, the desensitizing agent can well mix with other pyrotechnic mixture components uniformly so as to realize the function of reducing the mechanical sensitivity of a pyrotechnic mixture.

The invention provides a recrystallization process for refining 3-nitro-1,2,4-triazole-5-one, which comprises heating acetone through water-bath, controlling the temperature between 48-52 deg. C, completely dissolving 3-nitro-1,2,4-triazole-5-one, vacuum distilling, controlling the vacuity between 0.03-0.04 MPa, finally evaporating acetone completely to obtain the ultra-fine NTO particles.

The invention provides a gas production drug for safety belt pretention unit, which contains adhesives, nitrogen-contained organic compounds, oxidants and endorthermic agents; wherein, the content of the adhesives is larger than 10 per cent to 20 per cent, the content of the nitrogen-contained organic compounds ranges from 30 per cent to 55 per cent, the content of the oxidants ranges from 30 per cent to 55 per cent and the content of the endorthermic agents ranges from 4 per cent to 15 per cent in weight proportion with the total weight of the gas production drug as the datum. As the content of the adhesives is larger than 10 per cent to 20 per cent in weight proportion, the gas production drug for safety belt pretention unit provided by the invention not only has high gas production rate and leads to the favorable shrinkage performance of the safety belt, but also has low mechanical sensitivity and good safety, causes low noise and is low at temperature when being combusted so as to reduce the harms done to the passengers and vehicles.

The invention provides a high-thermal stability PBX explosive and a preparation method thereof. The explosive comprises, by mass, 84-88% of cyclotetramethylenetetranitramine, 8-12% of triaminotrinitrobenzene and 2-6% of a bonding system; and a binder in the bonding system is polyacrylate rubber HyTemp 4454, and a plasticizer in the bonding system is dioctyl sebacate or dioctyl phthalate. The preparation method comprises the following steps: dissolving the bonding system by analytically pure ethyl acetate through adopting a solvent volatilization process, carrying out vibrating dispersion on TATB in analytically pure petroleum ether, and pouring the obtained bonding system solution into an HMX explosive while stirring until the solvent is completely volatilized; and adding the obtained TATBsuspension, performing stirring for 1-2 h until the solvent volatilizes to form a paste, sieving the paste to form 0.5-1.0 mm particles, and drying the particles to obtain the PBX explosive. The PBXexplosive prepared in the invention has the advantages of high energy, low mechanical sensitivity and good thermal stability.

The invention relates to a hole sealing device for blasting water injection in a deep coal seam. The hole sealing device comprises a blasting mechanism and a water injection sealing device, wherein the blasting mechanism comprises an explosive chamber and an explosive, wherein the explosive chamber is of an I-shaped cylinder structure; the water injection sealing device is arranged at an opening of the coal seam and used for sealing the opening of the coal seam and an external space of a blasting mechanism to ensure that the blasting mechanism is completely detonated in a closed space. Hydraulic coupling blasting is combined with coal seam water injection to achieve integration of blasting and injection, the operation process is simplified, operation procedures are reduced, the work intensity of workers is reduced, direct water injection after loose blasting is achieved, the purposes of relieving pressure of the coal seam, shifting the stress forward, wetting coal bodies, improving theplasticity of the coal bodies and reducing dust production are achieved, and the technical problems are solved that in existing blasting and coal falling operation of the deep coal seam, the work intensity of the workers is high, inconvenience is caused during use, the hole sealing effect is poor, and hole sealing devices cannot be recycled. Compared with the prior art, the hole sealing device has the advantage of having a great market prospect and a great development space.

The invention discloses a preparation method for a graphene-based carbohydrazide metal complex crystal energetic material. The preparation method comprises the following steps: S1, dispersing graphene oxide with oxygen content of no less than 45% into water or an organic solvent for 30 to 60 min so as to obtain a graphene oxide suspension; reacting the graphene oxide suspension with a coupling agent at 55 to 65 DEG C for 1.5 to 2 h so as to obtain a graphene oxide activated precursor; dispersing the graphene oxide activated precursor in a dispersing agent I for 30 to 50 min, adding carbohydrazide and carrying out a reaction at 60 to 70 DEG C for 4 h so as to obtain carbohydrazide functionalized graphene oxide; and S4, subjecting the carbohydrazide functionalized graphene oxide prepared in step 3 to cleaning and filtering, then carrying out dispersion in a dispersing agent II for 15 to 60 min, adding a carbohydrazide solution, then adding nitrate or perchlorate, carrying out a reaction at 75 to 85 DEG C for 15 to 60 min and then carrying out vacuum drying so as to obtain the graphene-based carbohydrazide metal complex crystal energetic material. The graphene-based carbohydrazide metal complex crystal energetic material prepared by the invention overcomes the problems of low laser ignition efficiency and complex preparation technology of photosensitive insensitive energetic materials.

The invention discloses a method for spheroidizing a hexanitrohexaazaisowurtzitane (HNIW) explosive. The method comprises the following steps: I. adding explosive crystals into an etching liquid, heating to a certain temperature, mechanically agitating for certain time, and then filtering and washing the explosive; II. adding the explosive in the step I. into a surface polishing solvent, mechanically agitating at normal temperature, then filtering and washing materials, and drying to obtain the spherodized explosive crystals. The method is applicable to spheroidization of CL-20 crystals with various particle size and various crystal forms, is simple in technological flow, mild in reaction conditions, good in reproductivity, high in yield, and applicable to industrial batch production; the prepared spheroidized CL-20 explosive crystal product is approximately spherical, has less edges and smooth surfaces; the internal defects of the particle crystals are fewer, the open-setting stacking density is high, and the mechanical sensitivity is obviously reduced.