28 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 discloses high-performance brittle-crack-resistant steel for nuclear power pressure-bearing equipment and a manufacturing method of the high-performance brittle-crack-resistant steel. The high-performance brittle-crack-resistant steel comprises the following chemical components: 0.16%-0.24% of C, 0.20%-0.40% of Si, 1.25%-1.60% of Mn, less than or equal to 0.010% of P, less than or equal to 0.005% of S, 0.25%-0.45% of Cr, 0.25%-0.40% of Cu, 0.30%-0.50% of Ni, 0.005%-0.008% of Ca, 0.65%-1.25% of Mo and 0.04%-0.08% of V. The manufacturing method comprises the steps of smelting, continuous casting, heating rolling and heat treatment. The thickness of the steel plate is 30-120 mm, and through hardening and tempering and simulated postweld heat treatment, the normal-temperature tensile yield strength is larger than or equal to 620 MPa, the tensile strength is larger than or equal to 770 MPa, the 360-DEG C high-temperature tensile yield strength is larger than or equal to 518 MPa, the tensile strength is larger than or equal to 618 MPa, the impact absorption energy at the temperature of-40 DEG C is 195 J or above, the non-ductility transition temperature is smaller than or equal to-52 DEG C, and the grain size is larger than or equal to 8.5 grades. The steel provided by the invention has good mechanical properties and brittle crack resistance, and fully meets the requirements of steel for pressure-bearing equipment of a nuclear power unit.

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 materials, in particular to an anti-brittle fracture high-temperature alloy and a preparation method and application thereof. The embrittlement-resistant high-temperature alloy comprises a heterogeneous grain structure, the heterogeneous grain structure comprises a plurality of equiaxed grain areas and a plurality of columnar grain areas, each equiaxed grain area is formed by gathering equiaxed grains, each columnar grain area is formed by gathering columnar grains, and the average size of the columnar grains is larger than that of the equiaxed grains; the columnar grain areas and the equiaxed grain areas are distributed at intervals, and the total number of low-angle grain boundaries and coincident position lattice grain boundaries in formed grain boundaries is larger than that of high-angle grain boundaries. According to the high-temperature alloy, the equiaxed grain form in an existing high-temperature alloy is changed, starting from the angle of grain and grain boundary dual improvement or further from the angle of phase distribution, the brittleness of the high-temperature alloy is greatly reduced, and the cracking risk is reduced. The material can serve for a long time in a high-temperature environment and can be used for aero-engines, power units, oil and gas exploitation equipment, gas turbines and the like.

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.

The invention discloses a low-temperature nodular cast iron production process which specifically comprises the following steps: S1, raw material preparation, S2, smelting detection treatment, S3, spheroidizing inoculation treatment and S4, casting molding: the casting temperature is controlled to be 1340-1400 DEG C, the situation that the graphite spheroidizing rate is reduced due to high temperature is avoided, the raw materials are obliquely poured into a preheating mold, and surface burrs are cleaned after cooling; and S5, heat treatment. The invention relates to the technical field of metal material manufacturing. According to the low-temperature nodular cast iron production process, the prepared nodular cast iron has the tensile strength larger than or equal to 500 MPa, the impact absorbing energy larger than or equal to 15 J / cm < 2 > and the elongation larger than or equal to 18% in the environment of-60 DEG C, the tensile strength is obviously superior to the traditional QT400-18AL standard (the tensile strength is larger than or equal to 360 MPa, and the impact absorbing energy is larger than or equal to 12 J / cm < 2 >), graphite nodules are evenly distributed and regular in shape, the matrix ferrite proportion is larger than or equal to 85%, low-temperature brittle crack propagation is effectively inhibited, and the service life of the nodular cast iron and through an auxiliary pouring system and a segmented inoculation process, the pouring defect rate is reduced to 1% or below, and the production efficiency is improved by 20%.

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 copper-zirconium-titanium composite target material and a preparation method thereof, and belongs to the technical field of metallurgy. The composite target material is of a double-layer structure, one layer is a copper-zirconium-titanium alloy target material, and the other layer is a copper plate combined to one side of the copper-zirconium-titanium alloy target material. The copper-zirconium-titanium alloy target material consists of the following components in atomic percent: 40 to 70 percent of Cu, 20 to 50 percent of Zr and 1 to 10 percent of Ti. According to the copper-zirconium-titanium composite target material obtained through the preparation method, the copper-zirconium-titanium alloy target material layer is high in density, component control is accurate, the structure is uniform and free of segregation, the forming rate is high, and the brittle cracking problem of the target material can be 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 utility model relates to a PPR (pentatricopeptide repeats) pipe fitting capable of preventing low-temperature brittle cracking, which is used for connecting pipes and comprises a pipe inserting part and a reducing part, wherein the pipe inserting part is used for being connected with a pipe in a hot melting and inserting mode, the reducing part comprises a glue bearing groove used for containing welding overflowing glue and a connecting inclined face used for being connected with parts with different diameters, and the glue bearing groove comprises a guiding inclined face with one end making contact with a pipe body and a stop block located in the center of the glue bearing groove and used for limiting. Wherein the guide inclined surface is used for changing the thicknesses of different positions of the glue bearing groove to adapt to different ring stress requirements, and the stop block is used for limiting to prevent a pipe from being inserted too deep; according to the utility model, the reducing part is arranged at the welding part, and the glue bearing groove is formed in the reducing part, so that the problem that the pipe fitting is easy to brittle and crack in a low-temperature test due to stress concentration generated by extrusion of overflowing glue and the pipe fitting in a hot-melting socket-and-spigot process is solved.

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 invention relates to the technical field of wire welding, in particular to a thermocouple wire welding device which comprises a main body unit, a welding machine main body, a welding mechanism arranged on one side of the welding machine main body and a sealing mechanism arranged on one side of the welding machine main body and used for providing a sealing environment for welding. The air injection mechanism is arranged in the sealing mechanism and is used for injecting inert gas to the wire welding position; through the multi-sealing design of the sealing box, the corrugated sleeve, the annular bag body and the transparent glass cover, a relatively closed welding space is constructed, inert gas is sprayed to the welding position in cooperation with the gas spraying mechanism, a gas protection layer is formed for the wire welding position, and therefore the problems that the wire welding spot contact resistance is increased, the mechanical strength is reduced, and brittle cracks exist are solved; and meanwhile, after welding is completed, redundant inert gas is pumped out along with the wire and overflows, secondary protection can be formed on the welding spots in the cooling stage, and the welding quality of the wire is further improved.

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.

The invention relates to the technical field of sheet metal stamping, and provides a hot press forming method and stamping equipment. The hot press molding method comprises the following steps: heating a plate to an austenitizing temperature, and keeping the temperature for a set time length; and the plate is transferred to stamping equipment with a water bath condition, the plate is moved into a water bath before the temperature of the zinc-based plating layer is reduced to the melting point of the zinc-based plating layer, and stamping operation is conducted on the plate while the plate enters the water bath. According to the hot press forming method, under the condition that the zinc-based coating of the plate is still in liquid, the plate is moved into the water bath to be stamped, the high-temperature plate can instantly form an air film on the surface of the zinc-based coating of the plate after entering the water bath, the coating can be well protected against impact damage, and the service life of the plate is prolonged. The problem that liquid metal is prone to causing brittle cracks in the machining process of the zinc-based plating plate through existing direct thermal forming is solved, and therefore the direct thermal forming machining process suitable for the zinc-based plating plate is provided.

The invention relates to the technical field of engine component detection, in particular to an engine cylinder cover strength detection device which comprises a bottom cover and the like. A clamping assembly used for clamping an engine cylinder cover is installed in the bottom cover, heating test simulation assemblies are evenly arranged in the bottom cover, the firepower face of the engine cylinder cover makes contact with the heating test simulation assemblies, an upper cover is arranged above the bottom cover, and the upper cover is driven by a first driving assembly to move up and down. When the upper cover is in contact with the bottom cover, a closed space can be formed. The piston cylinder, the movable cover, the test rod and other parts are arranged, thermal load borne by an engine in actual work can be simulated through impact of high-temperature substances on a combustion chamber of an engine cylinder cover, meanwhile, the movable cover moves upwards, and then mechanical impact can be applied to the test rod; therefore, the brittleness, crack generation and expansion behavior of the cylinder cover at high temperature can be detected, and the judgment of the reliability of the material in long-term use is facilitated.

This invention provides a high-strength steel plate with excellent low-temperature toughness and brittle crack initiation suppression performance, based on a simplified manufacturing process using direct quenching and tempering. The steel plate of this invention has a specified composition, with a retained austenite content of less than 1.7% by volume (1 / 4 t), and a Charpy absorption energy of over 200 J at -196°C when using a full-size test piece and over 100 J when using a half-size test piece.