12 results about "Impact fracture" patented technology

The invention discloses a method and a device for removing a high-pressure casting pouring system. The method comprises the following steps: generating a preset fracture guide structure on one side of a product body in a connecting area of the product body and a pouring system; the high-pressure casting with the structure is moved along a first axis of movement and is engaged with the moving gating system in a predetermined position by means of a separation tool. Through the synergistic effect of continuous movement of the workpiece and meshing hindering of the separation tool, a composite separation force composed of a shearing force and a bending / drawing force is generated at the preset fracture guiding structure, and therefore the pouring system is separated accurately in a low-damage mode along a preset path. According to the method, through a two-step method of'preset guiding and dynamic composite force separation ', rough impact fracture is converted into a controllable and low-stress crack propagation process, the problems that a product body is prone to being damaged, the fracture surface quality is poor and the percent of pass is low in a traditional process are fundamentally solved, and the automation level and precision of removal operation and the product quality are remarkably improved.

The invention belongs to the field of high-temperature alloy powder metallurgy, and particularly relates to a method for improving the high-temperature plasticity of a GH4698 powder metallurgy workpiece and application. The method comprises the steps that GH4698 spherical powder is adopted for preparing a GH4698 alloy blank, the GH4698 alloy blank is pretreated to obtain a GH4698 alloy intermediate blank, the GH4698 alloy intermediate blank is subjected to heat treatment to obtain a GH4698 alloy workpiece, the high-temperature coordination deformation capacity between powder particles and the high-temperature coordination deformation capacity inside the powder particles of the prepared GH4698 alloy workpiece are enhanced, and the high-temperature coordination deformation capacity between the powder particles and the high-temperature coordination deformation capacity inside the powder particles are improved. The room-temperature impact fracture of the alloy part is mainly fracture in powder particles; under the condition of 750 DEG C, the tensile strength is larger than 880 MPa, the yield strength is larger than 720 MPa, the ductility is larger than 10%, and the percentage reduction of area is larger than 15%.

This invention discloses a surface hardening method for universal joints in screw drills and related universal joints. The method includes: performing heat treatment and finishing on a rough-machined universal joint blank to obtain the universal joint body; after preheating the universal joint body, spot welding a tungsten-cobalt alloy block wrapped with nickel-based brazing filler metal to the wear-resistant contact surface at one end of the universal joint body; spraying nickel-tungsten carbide powder and nickel-coated boron carbide composite powder onto the wear-resistant contact surface to form a hardened layer on the wear-resistant contact surface; after cooling, grinding the sprayed surface to the design dimensions; inspecting the porosity of the ground sprayed surface, filling the porosity with nickel-tungsten carbide powder and nickel-coated boron carbide composite powder, heating and melting to seal the porosity; and after cooling, precision grinding the universal joint to the design dimensions. This invention greatly improves the wear resistance and impact fracture resistance of the universal joint, enabling it to be used in conjunction with other screw drill components resistant to 350℃ high temperatures to form screw drills resistant to 350℃ high temperatures.

The high-temperature wire harness comprises a connecting device, a butt joint device and a limiting device are fixedly installed on the outer ring of the connecting device, the butt joint device comprises a first lantern ring, a guide rod and a protective cover, the guide rod is fixedly installed on the surface of the front end of the first lantern ring, the guide rod is annularly distributed, and the limiting device is fixedly installed on the first lantern ring. The protective covers are symmetrically and fixedly installed on the surface of the front end of the first lantern ring and located on the outer ring of the guide rod, the connecting device comprises a first cable and a second cable, the second cable is slidably inserted into the first cable, and the limiting device comprises a reset spring, a positioning plate, a supporting cavity, an arc groove and a second lantern ring. The reset springs are symmetrically and fixedly installed at the bottom end of the interior of the supporting cavity, and the positioning plate is fixedly installed at the top ends of the reset springs. Through the arrangement of the butt joint device and the limiting device, the purpose of reinforced protection of the high-temperature cable connection part is achieved.

The application discloses a kind of based on dot matrix laser scanning quantization welded joint impact fracture analysis system, method and device, and it is related to welding detection technical field.Solve the problem that existing impact toughness test evaluation method is influenced by model simplification, boundary condition setting and other factors, can only qualitative evaluation welded joint fracture mechanism in actual application.Analysis system includes: fracture sample clamping end, dot matrix laser emission and receiving system, motion platform, control and data processing system;Dot matrix laser emission and receiving system are composed of n dot matrix laser emitter and corresponding ranging receiving sensor unit;Motion platform and for dot matrix laser emission and receiving system one-dimensional direction horizontal motion;Fracture sample clamping end is used to fix the impact fracture sample of welded joint;Control and data processing system are used to control the dot matrix laser emission time sequence of n units and calculate the distance data of n position coordinate points.The application realizes the quantitative evaluation analysis of welded joint impact fracture.

The invention discloses a 500 MPa-grade super-thick steel plate for a low-yield-ratio bridge structure and a manufacturing method of the 500 MPa-grade super-thick steel plate. The steel plate is formed by smelting components in specific mass percent, and the steel plate is manufactured by strictly controlling the processes of KR molten iron pretreatment, BOF converter rough smelting, LF refining, RH vacuum treatment, continuous casting, heating, rolling, accelerated cooling, tempering and the like. The thickness of the steel plate is 100-130mm, and the steel plate has high strength (Rp0.2 is greater than or equal to 500MPa, Rm is 630-750MPa, and A is greater than or equal to 18%), low yield ratio (less than or equal to 0.83), high toughness and brittle failure resistance (longitudinal and transverse KV2 is greater than or equal to 160J at-60 DEG C and the impact fracture shear section rate is greater than or equal to 85% at the position of 1 / 4 of the thickness, and longitudinal and transverse KV2 is greater than or equal to 120J at-40 DEG C and the impact fracture shear section rate is greater than or equal to 70% at the position of 1 / 2 of the thickness) and excellent comprehensive performance (CET is less than or equal to 0.30%, and Pcm is less than or equal to 0.23%), and can

The application discloses a kind of two-dimensional static load under plate rock impact fracture experimental device and method, belong to rock mechanics experimental field.The plate rock dynamic and static loading fracture experimental device is carried out by design, including the steps of preparing test instrument, installing sample, setting experimental parameters, starting experiment and data image processing;Plate rock dynamic and static loading fracture experimental device includes Hopkinson pressure bar experimental system, axial static load loading system, lateral static load loading system, plate rock sample and crack real-time monitoring system, etc.The device can adapt to any placed inclination of plate rock sample during experiment without affecting the independent application of axial static load and impact dynamic load on its left and right ends and lateral static load on its upper and lower ends, as well as the arrangement of monitoring system.It is simple in structure, easy to disassemble and assemble, highly adaptable, easy to use, and can meet the requirements of two-dimensional static load and impact dynamic load coupling under plate rock sample dynamic and static mechanical property experiment and non-contact real-time monitoring of fracture process.

The present invention relates to the technical field of metallurgy, and discloses an ultra-wide Q500qD bridge plate and a production process therefor. The ultra-wide Q500qD bridge plate comprises the following chemical components in percentages by mass: 0.09-0.11% of C, 1.60-1.65% of Mn, 0.55-0.70% of Cr, less than or equal to 0.012% of P, less than or equal to 0.010% of S, 0.035-0.045% of Nb, 0.001-0.007% of V, 0.020-0.035% of Ti, 0.05-0.09% of Mo, and the balance of Fe and inevitable impurities. In the present invention, by using a component design with a low C content, adding Nb, Ti, Cr and Mo for compounding, and using a special rolling and controlled-cooling mode, a steel plate having a multi-phase structure consisting of bainite, ferrite and an extremely small amount of martensite is obtained, ensuring that the strength, the extremely low yield ratio, the impact energy at a low temperature of -20°C, the percentage of fibers on an impact fracture surface and the aging impact energy meet the requirements. Moreover, the Q500qD steel plate produced by means of common normalizing or tempering has a high yield ratio and a relatively small margin in terms of impact toughness.

This invention provides a method and impact-type fracturing device for hard rock, relating to the field of engineering development technology. The method includes: forming multiple pre-splitting holes with small intervals along the outline of the working face at its edge; forming a larger central compensation hole at the center of the working face; dividing the area between the central compensation hole and each pre-splitting hole into multiple impact rock-breaking points; inducing rock-breaking at these points to create a continuous path that extends from the impact rock-breaking points towards the pre-splitting holes and the central compensation hole, and these paths become interconnected. By constructing a "pre-splitting weakening - central stress relief - multi-point synergistic impact" approach, controllable expansion and connection of the crack network at the working face are achieved, allowing the cracks to form stable continuous paths under weakened structural constraints. This method not only utilizes the central compensation hole for stress relief and induced stress redistribution, reducing the required rock-breaking capacity, but also results in a more uniform distribution of the continuous path, reducing the dispersion of rock block size.

The utility model discloses an extensometer protection device for high-temperature stretching, which relates to the field of metal high-temperature stretching detection, comprises a sliding rail, and is characterized in that the upper part of the sliding rail is connected with a first sliding seat and a second sliding seat in a sliding manner, and the upper parts of the first sliding seat and the second sliding seat are respectively and fixedly provided with a base; a frame body is fixedly installed on the upper portion of the base, an extensometer body is slidably connected to the position, between the first sliding base and the second sliding base, of the upper portion of the sliding rail, and locking devices are arranged on the front portion of the first sliding base and the front portion of the second sliding base. According to the extensometer protection device for high-temperature stretching, the first sliding seat and the second sliding seat are arranged on the sliding rail and support the frame body, and the frame body wraps the extensometer main body, so that the ceramic rod of the extensometer main body is not influenced to extend out when the extensometer protection device is used, and the extensometer main body and the ceramic rod of the extensometer main body can be surrounded on the inner side when the extensometer protection device is not used; and moreover, the size of the frame body is adjustable, and the application range is wide.

The application belongs to the field of high-temperature alloy powder metallurgy, and particularly relates to a method for improving the high-temperature plasticity of a GH4698 powder metallurgical part and application thereof. The method comprises the following steps: preparing a GH4698 alloy blank by using GH4698 spherical powder, pretreating the GH4698 alloy blank to obtain a GH4698 alloy intermediate blank, and heat-treating the GH4698 alloy intermediate blank to obtain a GH4698 alloy part. The high-temperature coordinated deformation capacity of the obtained GH4698 alloy part is enhanced, and the room-temperature impact fracture of the alloy part is mainly caused by the internal fracture of the powder particles. Under the condition of 750 DEG C, the tensile strength is greater than 880 MPa, the yield strength is greater than 720 MPa, the elongation is greater than 10%, and the reduction of area is greater than 15%.

The present application belongs to the technical field of material fracture mechanics test, and discloses a metal material ductile-brittle transition temperature confirmation method. Based on selected samples and determined test temperature range, impact tests, fracture toughness tests are carried out on the selected samples at different temperatures, and experimental data are recorded. Based on the experimental data of each sample obtained at different temperatures, experimental data points are plotted, and the ductile-brittle transition temperature is obtained based on the experimental data points. The Charpy impact CVN, fracture toughness CTOD / J test data at five different temperatures can be used to calculate the ductile-brittle transition temperature. The present application can obtain accurate ductile-brittle transition temperature value through five effective tests, effectively reducing the test cost and time. Especially for the characteristics of high-strength structural steel ring weld joint toughness dispersion, the present method can quickly and accurately obtain the ductile-brittle transition temperature of high-strength structural steel and ring weld joint DBTT CTOD50 、 DBTT CVN50 and DBTT J50 .