10 results about "Fracture load" patented technology

The present invention relates to a protective helmet (1) comprising spacing elements (11) between an inner shell (102) and an outer shell (101), wherein a first spacing portion (111) is shaped in such a way as to at least partly accommodated a second spacing portion (211) in such a way that, in the event of an impact, said first spacing portion (111) and said second spacing portion (211) are able to be moved in a defined absorption stroke between a mating position and a maximum absorption position, wherein said second spacing portion (211) is housed within said first spacing portion (111) for a maximum height, wherein the first (111) and second (211) spacing portions are able to be solidly coupled at the mating portion (311) having a breaking load lower than the breaking loads of the outer shell (101) and inner shell (102), and wherein at the mating position the second spacing portion (211) is arranged outside the first spacing portion (111) and at the maximum absorption position the first spacing portion (111) is shaped in such a way as to at least partly accommodate the second spacing portion (211) following the breakage of the mating portion (311).

A method for predicting the fracture toughness of graphene and whisker synergistically strengthened ceramic composites is proposed. Based on whisker and graphene modeling methods, two-dimensional structural models of whiskers and graphene are sequentially embedded in the ceramic composite matrix to generate the required whisker / graphene / ceramic composite model. A fracture toughness prediction model for the whisker / graphene / ceramic composite is constructed. This model is then imported into Abaqus software to configure material parameters and boundary conditions, and fracture toughness simulation is performed. Finally, the maximum fracture load is extracted, and the fracture toughness of the whisker and graphene synergistically strengthened ceramic composite is calculated using a novel fracture toughness calculation method, thus completing the fracture toughness prediction. This invention can quickly model graphene, whiskers, and the ceramic matrix, efficiently and accurately predict the optimal content of graphene and whiskers, as well as the fracture toughness of the ceramic composite, providing an effective aid to experimental methods.

A device for manipulating threaded joints, the device including a set of tongs (32), a threaded rod (72), and a break-away member (96a) configured to fracture at a predetermined fracture load to prevent tension in the threaded rod beyond a predetermined tension limit. The set of tongs is formed by a first wrench (36) configured to engage a first member of a threaded joint and a second wrench (40) configured to engage a second member of the threaded joint. The first wrench includes a first lever arm (46) and the second wrench includes a second lever arm (48). The threaded rod is engaged with the first lever arm and the second lever arm to urge the first and second lever arms toward each other through tension in the threaded rod. The threaded rod is configured to maintain tension at the predetermined tension limit upon fracture of the break-away member.

The utility model provides tungsten wire diamond wire bus strength detection equipment, which relates to the technical field of metal material detection, and comprises a base, the top of the base is fixedly connected with a protection box, the inner surface wall of the protection box is fixedly connected with two first guide rods, and a first moving plate is movably sleeved between the outer surface walls of the two first guide rods; the bottom of the inner wall of the protection box and the bottom of the first moving plate are fixedly connected with mounting frames, and the inner surface walls of the two mounting frames are fixedly connected with first clamping blocks. According to the clamping device, secondary clamping of the tungsten wire diamond wire bus is achieved under the interaction of all the components of the clamping device, and the double clamping structure prevents the bus and the clamping components from slipping or falling off by increasing the clamping force and the friction coefficient of the contact surface; it is ensured that the actual fracture load of the material is achieved in the limit load test of the tungsten filament with the limit high rigidity, and the detection precision is guaranteed.

The present invention relates to the technical field of dental materials, and provides an antibacterial resin mixture, and a preparation method therefor and the use thereof. A resin-infiltrated ceramic composite material prepared by infiltrating the antibacterial resin mixture provided in the present invention into a porous ceramic framework and a dental material prepared from the antibacterial resin mixture with a component (2) can kill oral pathogenic bacteria around a prosthesis and effectively prevent secondary caries. Moreover, compared with existing resin-infiltrated ceramic composite materials, the materials have significantly improved mechanical properties, especially significantly improved fracture load, thereby improving the fracture resistance of the existing resin-infiltrated ceramic composite materials, and have good esthetic properties, thereby prolonging the service life of a prosthesis and enabling a prosthesis material to better utilize the excellent properties thereof during service.

This invention belongs to the field of dental restoration technology, and provides an interface activator, its preparation method, application, and application method, solving the problems of weak bonding or insufficient long-term bonding stability of dental zirconia. The interface activator is prepared from raw materials containing the following molar fractions: 50-60 mol% silica, 10-30 mol% alumina, 10-30 mol% magnesium oxide, and 1-6 mol% zirconia. The raw materials are mixed and sequentially melted and crystallized to obtain microcrystalline glass; the microcrystalline glass, solvent, and colorant are then mixed to obtain the interface activator. The activator of this invention, through optimized composition, lowers the temperature during crystallization heat treatment during use; and after application and further heat treatment, it effectively improves bonding strength and durability, reduces the possibility of chipping and detachment of ceramic dentures, and effectively enhances the fracture load and deformation resistance of ceramic dentures.

The application discloses an experimental device for simulating fracture failure of anti-slide piles and a use method thereof, belongs to the technical field of geotechnical engineering reinforcement, adopts modular design, and comprises a pile top module, at least one pile middle module, a pile bottom module and a plurality of variable cross-section ultimate load limiting modules; the pile middle module is an upper and lower plate structure hinged by a flat hinge, the modules are slidably connected through convex and concave guide rails, the ultimate load limiting modules are inserted into aligned wedge-shaped holes, fracture occurs at the middle weak part when the ultimate load is reached, and shear failure and bending failure of the anti-slide pile can be simulated respectively. The fracture load can be accurately controlled by adjusting the thickness of the limiting module, the application has the advantages of simple structure, convenient disassembly and assembly, reusability, high test precision and suitability for research on the fracture failure mechanism of the anti-slide pile under different working conditions.

The present invention provides a novel method for manufacturing a fiber-reinforced plastic molded article, and a novel fiber-reinforced plastic molded article. [Solution] A method for manufacturing a fiber-reinforced plastic molded article, comprising press-molding a nonwoven fabric containing a fiber-reinforced material and a thermoplastic resin to obtain a molded article having a porosity of 1.0 to 29.0%. By this manufacturing method, a fiber-reinforced plastic molded article is produced that contains a thermoplastic resin and a plurality of fiber-reinforced materials oriented in a predetermined direction, and the coefficient of variation (CV) of the bending fracture load measured for each test piece obtained by dividing the molded article into eight equal parts in a width direction perpendicular to the predetermined direction is 6.0% or less.

The invention belongs to the technical field of hydrogen conveying pipeline performance testing, particularly relates to a testing method for determining critical fracture stress of a pipeline girth welding joint in a hydrogen environment, and aims to solve the problems that an existing testing method is too high in time cost, one-sided in evaluation and the like. The method comprises the following steps: processing a tensile sample of a transverse notch of a ring welding joint in the center of a welding seam to obtain N samples; calculating a notch root sectional area based on a transverse notch size of a ring welding head of a weld center; applying a load to the first sample in an air environment at a displacement rate required by a tensile standard until the first sample is fractured to obtain a maximum load; based on the maximum load, carrying out graded loading and holding tensile tests on the second sample to the Nth sample in sequence at a set stress rate to obtain a critical fracture load of each sample; and calculating critical fracture stress based on a threshold load and the notch root sectional area. According to the method, the accurate critical fracture stress value can be obtained, and the basis is provided for comparison of the hydrogen induced cracking resistance of the pipeline girth welding joint.

The application discloses a true triaxial condition rock fracture toughness testing device and testing method, and relates to the technical field of rock mechanics and engineering; the testing device comprises a lateral confining pressure loading system located in a loading chamber; the loading chamber is located between a pressurizing base and a cover plate, and the three form a sealed space; hydraulic oil is continuously filled into the sealed space to apply confining pressure on a rock test piece in the vertical direction; an upper loading column is installed at the bottom of the cover plate, and the upper loading column is in contact with the rock test piece as a fracture fulcrum; a vertical load loading plate is arranged on the pressurizing base, and a lower loading column is fixed on the vertical load loading plate; the lower loading column is lifted under the drive of a hydraulic drive to apply fracture load on the rock test piece; the application can restore the three-direction stress state of the rock under the ground, test the rock fracture toughness under different three-direction confining pressure conditions, and provide important parameter support for the compressibility evaluation of unconventional oil and gas resources and the fracturing engineering design.