19 results about "Brittle crack" patented technology

The utility model belongs to the technical field of disc type filters, and particularly discloses a joggle joint lining center shaft of a disc type filter, which comprises a shaft body, a plurality of runners extending along the axial direction of the shaft body are arranged in the shaft body, special-shaped liners are respectively arranged in the runners in a matched mode, the special-shaped liners comprise a plurality of lining assemblies which are connected along the axial direction of the runners, and the lining assemblies are arranged in the shaft body. The adjacent lining assemblies are connected through mortise and tenon joint structures which are arranged in a matched mode, cavities in the middles of the lining assemblies are communicated with one another to jointly form a slurry channel for slurry to flow, and due to the sectional design of the special-shaped lining, the phenomena of brittle cracking and stripping caused by thermal stress of the whole ceramic tube are thoroughly avoided; the sectional joggle joint design of the special-shaped linings ensures accurate positioning of the adjacent ceramic special-shaped pipe sections in the axial direction and the circumferential direction, the concentricity, the connecting strength and the sealing performance of the linings are good, and the special-shaped lining is particularly suitable for a filter to filter high-abrasiveness and high-corrosivity slurry.

The invention relates to the technical field of road engineering materials, and particularly discloses an ultra-thin anti-sliding layer material based on industrial solid waste. According to the composite filler provided by the invention, the waste plastic, the fly ash and the polymer coated rubber powder are compounded, and a continuous network or sea island structure is formed by the waste plastic, so that rubber powder particles are effectively locked, and the softening flow of the rubber powder particles at high temperature is inhibited, thereby greatly improving the rut resistance of an anti-skid layer material; the elastic particles of the rubber powder are also used as stress concentration points and flexible buffer units, so that the brittle crack propagation of the plastic phase at low temperature is prevented, and the low-temperature crack resistance is improved; the silanized fly ash serves as rigid particles and is dispersed in an organic matrix, when the material is stressed, the rigid particles can bear and disperse stress and improve modulus and compressive strength, after the material is treated by a silane coupling agent, the fly ash particles and organic phases (rubber powder and plastic) form chemical bonds or strong physical adsorption, stress is effectively transmitted at an interface, and the mechanical property of the material is improved. The toughness of the material is improved.

The invention relates to the technical field of metal processing, and discloses a three-dimensional metal trademark manufacturing process which comprises the following steps: preparing a coating composition from the following raw materials: modified silicon dioxide nanoparticles, oxidized polyethlene wax emulsion and alkali-soluble acrylic resin emulsion; an aluminum alloy base material is selected, the back face of the aluminum alloy base material is milled to be thin, the front face is subjected to anodic oxidation and hole sealing treatment, and a coating composition is coated to form a protective coating; stamping forming is carried out, extrusion stamping is carried out through cooperation of corner heightening convex points of an upper die punch and corner deepening concave pits of a forming insert, and the base material is forced to plastically flow to fill character grooves; after forming, a top coating and surface metal are removed through CNC cutting, metal three-dimensional characters are reserved, and the remaining coating is cleaned and removed through a weak alkaline solution. The stress dispersion and lubrication performance of the coating is utilized, brittle cracking and whitening of the anodic oxide film in the stamping process are effectively prevented, and the three-dimensional metal trademark with the sharp contour, the complete side face oxidation and the highlight top face is obtained in cooperation with the cutting technology.

The invention discloses an impact-wear-resistant flux-cored wire for welding a high-manganese steel lining plate and a surfacing method, belongs to the technical field of surface engineering, and aims to solve the problems that a traditional high-manganese steel lining plate is embrittled, a surfacing layer is peeled off and deformed and the like. A flux core of the flux-cored wire comprises high-carbon ferrochrome powder, micro-carbon ferrochrome powder, graphite powder, ferrosilicon powder, ferromanganese powder, ferrotitanium powder, ferromolybdenum powder, ferrovanadium powder, ferroboron powder, calcium fluoride powder and nickel powder; the balance is iron powder; the outer skin is a low-carbon cold-rolled steel strip, the diameter is 2.4-3.2 mm, and the filling rate is 42-50%; the surfacing method comprises the steps that pretreatment and drying are conducted, plasma arc automatic surfacing is adopted, the current ranges from 135 A to 180 A, the welding speed ranges from 350 mm / min to 650 mm / min, the wire feeding speed ranges from 1800 mm / min to 2200 mm / min, compressed gas and protective gas are both argon, and the surface temperature of the high manganese steel lining plate is controlled; through solid solution of the nickel powder and weak self-protection of the calcium fluoride powder, the surfacing layer is high in hardness, high in wear resistance, small in matrix deformation and free of interface cracking.

The application discloses an electrode cap for resistance spot welding, which comprises a front end part, a trunk part and a transition part. The front end part is the part that first contacts the material to be welded during welding, and the outer arc surface of the front end part is formed by rotating a preset circular arc as a generatrix and taking the central axis of the electrode cap as a rotation center. The bottom of the trunk part is provided with a cavity, and the electrode cap is assembled with an electrode rod through the cavity. The outer cylindrical surface of the trunk part is formed by rotating a preset straight line as a generatrix and taking the central axis of the electrode cap as a rotation center. One end of the transition part is connected with the front end part, and the other end of the transition part is connected with the top of the trunk part. The outer arc surface of the transition part is formed by rotating a preset arc line as a generatrix and taking the central axis of the electrode cap as a rotation center, and the preset circular arc and the preset arc line are tangent. The application solves the technical problem of brittle cracks of liquid metal in the welding joint.

A structurally enhanced analyte sensor (41) is disclosed having a plurality of substrates (411a, 411b, 411d, 411e, 411f). After prefabrication of the substrates (411a, 411b, 411d, 411e and 411f) is completed, the substrates are combined into a whole through adhesion, so that insulation failure caused by insufficient curing of substrate materials can be avoided, brittle cracks are avoided, electric signal crosstalk between wires or electrodes is further prevented, noise generated in detection signals is further prevented, and meanwhile, the detection accuracy is improved. At least one protective layer (412) is arranged on the surface of the substrate (411) and covers at least the edges of the electrodes (4131, 4231 and 4331), the adhesive force between the edges of the electrodes (4131, 4231 and 4331) and the substrate (411) is increased, and the edges of the electrodes (4131, 4231 and 4331) are prevented from curling, bubbling and falling off. Meanwhile, the protective layer (412) can also increase the mechanical strength of the substrate (411) of the sensor (41), prolong the service life of the sensor (41), and improve the detection reliability of the sensor (41).

A cold rolling line, a steel sheet production line, a cold rolling method, and a steel sheet production method can suppress work roll deformation and brittle cracking during rolling. The cold rolling line includes one or more cold mills configured to inject coolant towards a work roll and a metal steel strip and to cold roll the metal steel strip, rollers provided upstream from the one or more cold mills in a conveyance direction of the metal steel strip and used to convey the metal steel strip, and a control unit that controls a height difference of the rollers. The control unit controls the rollers so that the metal steel strip is at a lower position towards a downstream side in the conveyance direction at an upstream side of at least a portion of the one or more cold mills including a most upstream mill provided farthest upstream.

The application discloses a method for evaluating viscoelastic cracking performance of rubber asphalt mixture, and aims at solving the problem that current evaluation of cracking performance of rubber asphalt mixture is limited to brittle cracking at low temperature and does not involve evaluation of viscoelastic cracking performance. The evaluation method comprises the following steps: 1, cutting a Marshall test piece; 2, image recognition; 3, performing an indirect tensile test on the Marshall test piece of the asphalt mixture to determine a control load; 4, collecting photos of the asphalt mixture in a loading process of the indirect tensile test; 5, calculating and obtaining a surface strain field of the Marshall test piece of the asphalt mixture in the indirect tensile test process; 6, calculating a high strain index to determine a high strain area proportion; 7, calculating a viscoelastic protection index; 8, constructing a discrete element test piece model; 9, performing indirect tensile simulation; 10, counting mortar tension chains; 11, calculating a mortar tension chain score; and 12, evaluating. The application combines the image recognition technology and the discrete element modeling, and effectively improves the accuracy of the evaluation result.

The application relates to the technical field of high polymer materials, and discloses a low-temperature brittle-fracture-resistant mulch film as well as a preparation method and application thereof. The low-temperature brittle-fracture-resistant mulch film is prepared from the following raw materials: PLA, PBAT, PE and a compatibilizer. The compatibilizer comprises PLA-PEG-NH2 and polyolefin grafted maleic anhydride. Through the technical scheme, the problem that PE is incompatible with polar PBAT and PLA in related technologies, leading to the low-temperature brittle fracture of the mulch film, is solved.

The invention discloses a kind of welding high manganese steel lining plate's impact wear resistant flux-cored wire and surfacing method, belong to surface engineering technical field, for the problem such as traditional high manganese steel lining plate brittle crack, surfacing layer peeling and deformation, flux-cored wire: high-carbon chromium iron powder, micro-carbon chromium iron powder, graphite powder, silicon iron powder, manganese iron powder, titanium iron powder, molybdenum iron powder, vanadium iron powder, boron iron powder, calcium fluoride powder, nickel powder, the balance is iron powder;Outer skin is low-carbon cold-rolled steel strip, diameter 2.4~3.2mm, filling rate 42~50%;Surfacing method: pretreatment, drying, adopt plasma arc automatic surfacing: current 135~180A, welding speed 350~650mm / min, wire feeding speed 1800~2200mm / min, compressed gas and protective gas are argon, control high manganese steel lining plate surface temperature;The invention realizes that surfacing layer hardness is high, wear resistance is strong, substrate deformation is small and there is no interface cracking by nickel powder solid solution, calcium fluoride powder weak self-protection.

This invention discloses a high-performance steel for nuclear power plant pressure-bearing equipment resistant to brittle cracking and its manufacturing method. The chemical composition is: C 0.16~0.24%, Si 0.20~0.40%, Mn 1.25~1.60%, P≤0.010%, S≤0.005%, Cr 0.25~0.45%, Cu 0.25~0.40%, Ni 0.30~0.50%, Ca 0.005~0.008%, Mo 0.65~1.25%, V 0.04~0.08%. The manufacturing method includes smelting, continuous casting, hot rolling, and heat treatment. The steel plate, with a thickness of 30-120 mm, undergoes quenching and tempering and simulated post-weld heat treatment. At room temperature, its tensile yield strength is ≥620 MPa and tensile strength is ≥770 MPa; at 360℃, its tensile yield strength is ≥518 MPa and tensile strength is ≥618 MPa; its impact absorption energy at -40℃ is above 195 J; its non-ductile transition temperature is ≤-52℃; and its grain size is ≥8.5. This invention possesses excellent mechanical properties and resistance to brittle cracking, fully meeting the requirements for steel used in pressure-bearing equipment of nuclear power units.

The invention provides an injection molding part for a freezing chamber and a preparation method of the injection molding part, belongs to the field of manufacturing of injection molding parts for freezing chambers, and aims at solving the problems that in the prior art, an injection molding process is short in closed loop, poor in parameter adaptation, prone to embrittlement at low temperature and insufficient in size precision. The preparation method comprises the steps from raw material preprocessing to whole-process maintenance, a closed loop is formed through intelligent sensing, decision making and execution, a decision making module comprises exclusive algorithms such as risk prediction, and data iterative optimization of every 500 / 1000 moduli is matched. The injection molding part is prepared by the method, the main body is polypropylene, the panel is transparent polystyrene, food grade and environmental protection standards are met, embrittlement is avoided at the temperature of-18 DEG C or below, the critical dimensional tolerance is smaller than or equal to + / -1.8 mm, and the process stability and the product reliability are improved.

One embodiment of the present invention provides an ultra-thick structural steel having excellent brittle crack initiation resistance, and a manufacturing method therefor, the ultra-thick structural steel comprising, by wt %, 0.03-0.08% of C, 1.6-2.2% of Mn, 0.6-1.3% of Ni, 0.005-0.03% of Nb, 0.005-0.02% of Ti, 0.1-0.4% of Cu, 100 ppm or less of P, 40 ppm or less of S, 1.5 ppm or less of H, and the balance of Fe and other inevitable impurities, wherein the sum of acicular ferrite and granular bainite in the microstructure is 80% or more by area fraction, the sum of the total length of cracks having a size of 30 μm or more per unit area of 1 mm2 in a ±1 mm region on the basis of the thickness center of the steel is 130 μm or less, and the yield strength is 500 MPa or more.

The invention relates to the technical field of weathering resistant steel grade smelting processes, and particularly discloses a production method of American standard weathering resistant steel A588GR.A steel grade. The production method comprises the steps that S1, production organization control is conducted, specifically, the mass percent of smelting components of strip steel with different thickness standards is controlled, and the slab charging temperature is smaller than or equal to 400 DEG C; s2, heating process optimization: controlling the time of a plate blank in a heating furnace, and controlling the furnace temperature; s3, setting rolling process parameters: setting different finish rolling inlet temperatures, finish rolling temperatures, coiling temperatures and cooling strategies according to different thickness standards of the strip steel; s4, quality control: strictly executing surface quality inspection, and controlling surface microcracks of the finished steel coil; copper brittle cracks on the surface of the steel coil are remarkably reduced, and the appearance and using performance of the product are improved; the fault rate and the rejection rate in the production process are reduced through optimized rolling parameters and cooling strategies, and the production efficiency is improved; the energy consumption and the waste of alloy elements are reduced, and the production cost is reduced.

The present application belongs to the field of hydrogen transmission pipeline safety evaluation, and provides a method for evaluating the hydrogen-induced brittle cracking resistance of a backing weld of a pipe girth joint. A single-edge notched specimen of the pipe girth joint is installed on a testing machine, and the specimen is placed in a temperature-controlled high-pressure environment box. A pressure head applies a load to the specimen at a slow displacement growth rate until the specimen breaks, and a load-displacement curve is recorded. The maximum load on the load-displacement curve is taken as the load at which a crack is generated, and the envelope area of the load-displacement curve before the maximum load is reached is taken as the crack formation work. The envelope area of the load-displacement curve after the maximum load is exceeded is taken as the crack propagation work, and the resistance of the material to cracking and crack propagation under the corresponding environment is evaluated. The sensitivity of the material to hydrogen-induced brittle cracking is evaluated according to the fracture morphology, and fibrous cracking is ductile cracking, and crystalline cracking is brittle cracking. The present application solves the problem that the backing weld is difficult to evaluate in terms of safety according to the existing material hydrogen environment compatibility test method due to the small thickness.

The invention discloses an atmospheric plasma thermal barrier coating finite element modeling method and system, and the method comprises the steps: S1, simplifying pores in a ceramic layer into circular holes based on the defect structure characteristics of an atmospheric plasma spraying coating, removing microcracks, and determining the porosity range; s2, acquiring engineering stress-strain data of the substrate layer material at the service temperature, and converting the engineering stress-strain data into real stress-strain data; s3, based on the pore simplification rule and the material data, generating a 2D geometric model containing random circular pores through a programmed script; s4, importing the pore parameters into a Python script, and dynamically constructing a finite element model; and S5, applying a Brittle Cracking criterion to the finite element model to simulate erosion failure. According to the method, complex structure defects in the ceramic layer are separated into single variables such as porosity, pore size and pore distribution, independent research and quantitative prediction are carried out, and blade erosion mechanism analysis and preparation process improvement are guided.

The present application relates to the technical field of building materials, in particular to a kind of high-strength artificial wall sand and its preparation method and application.The present application forms base sand by sodium hexametaphosphate auxiliary cleaning, gradation reconstruction treatment mechanism sand;Then use dopamine and tris to construct biomimetic intermediate layer, and induce iron-calcium-silicon mineral precursor to form organic-inorganic hybrid coating, finally by calcium hydroxide mineralization curing and silane gas phase grafting;With low crushing index, high interfacial bonding strength and excellent impermeability, effectively solve the deep engineering interface loose, high pressure leakage and brittle cracking problem.The material is especially suitable for deep oil and gas cementing, water-rich stratum water curtain, submarine tunnel lining and nuclear waste geological disposal repository and other high water pressure, high confining pressure engineering field.

This invention relates to the field of injection molding technology, specifically to a method for injection molding an insulating cover for terminal blocks and a transparent insulating cover. The method includes monitoring dynamic process parameters during the injection molding stage, including the integral value of the holding pressure curve, the peak value of the melt pressure in the mold cavity, and the pressure fluctuation value of the hydraulic system. The dynamic process parameters are analyzed to obtain the internal stress risk coefficient of the insulating cover under the current injection cycle. Annealing process parameters are determined based on the internal stress risk coefficient, and the insulating cover is annealed according to these parameters. The annealing process parameters include holding temperature and holding time. The molding method and the insulating cover prepared by this invention achieve targeted control of the root cause of internal stress, significantly improving the mechanical toughness of the insulating cover and greatly reducing the risk of brittle cracking due to residual stress during subsequent winding-unwinding dynamic installation and use. Simultaneously, it improves the quality consistency and reliability of the finished product.

The invention relates to a eutectic structure reinforced wear-resistant coating and a preparation method thereof, and belongs to the technical field of surface materials. The preparation method of the eutectic structure reinforced wear-resistant coating comprises the following steps: mixing raw material powder of the coating to obtain mixed powder, wherein the raw material powder of the coating comprises 2.5-4wt% of ferromanganese powder; 5 to 10 weight percent of ferroniobium powder; 0.8 wt.% to 1 wt.% of ferrosilicon powder; 10 to 11 wt% of high carbon ferro-chrome; 2-3 wt% of low-carbon ferrochrome; 0.3 to 0.48 wt.% of pure nickel powder; the balance is spherical iron powder; and the mixed powder is deposited on the surface of a 60CrMnMo forged steel base material in a laser cladding mode, and the wear-resistant coating with the strengthened eutectic structure is prepared. The raw material melting point is reduced, the element yield is increased, and the preparation cost is reduced. The method effectively inhibits the growth of the coating along crystal brittle cracks.