956 results about "Slow cooling" patented technology

The invention relates to a hot-rolled wire rod for a 2230 MPa grade stranded wire and a manufacturing method of the hot-rolled wire rod, after a Cr-Nb-Al high-carbon component design is rolled and spun into a wire rod, the wire rod is subjected to online molten salt isothermal toughening treatment, so that the wire rod is firstly subjected to front-section molten salt treatment and enters a sorbite phase region from an austenite state to form a structure taking a sorbite structure as a main structure; and then carrying out rear-section molten salt treatment, reducing the circulation volume of molten salt, promoting the unconverted retained austenite to be continuously converted into sorbite, carrying out isothermal tempering, promoting fusing of a part of sorbite lamellar layers, and finally carrying out slow cooling through a roller way, so as to prepare the hot-rolled wire rod of which the microscopic structure comprises a mixed structure consisting of tempered sorbite, ferrite and fused sorbite, the material cost can be controlled, the tensile strength is 1513-1563 MPa, the percentage reduction of area is 31%-36%, and the structure uniformity and the production efficiency are both considered, so that off-line heat treatment is avoided during stranded wire manufacturing, and the drawing pass and the cracking risk are reduced.

The invention relates to a hot-rolled wire rod for a 2060MPa-grade stranded wire and a manufacturing method of the hot-rolled wire rod. Mn-Cr high-carbon chemical component design and rolling spinning are performed to form a wire rod, then online molten salt isothermal phase change treatment is performed, the wire rod is firstly subjected to front-section molten salt treatment and enters a sorbite phase region from an austenite state to form a structure taking a sorbite structure as a main structure, and then the wire rod is subjected to rear-section molten salt treatment, so that the hot-rolled wire rod is obtained. The method comprises the following steps of: firstly, carrying out heat treatment on the residual austenite, promoting the unconverted residual austenite to be converted into a sorbite structure, simultaneously promoting isothermal tempering of the structure and fusing of a part of sorbite lamellas, and finally, slowly cooling through a roller way to prepare a hot-rolled wire rod of which a microscopic structure comprises a mixed structure consisting of tempered sorbite, tempered ferrite and fused sorbite, so that the material cost can be controlled; the high-strength and high-plasticity performance matching of the wire rod is improved, the tensile strength is 1370-1420 MPa, the percentage reduction of area is 35%-40%, and the mechanical property fluctuation is reduced, so that the wire breaking risk in stranded wire production is reduced, and efficient and stable production is promoted.

The invention relates to a 1200MPa-grade high-strength tool steel wire rod and a manufacturing method thereof, after V-containing chemical components are designed, rolled and spun into a wire rod, the wire rod is subjected to online molten salt isothermal quenching treatment, and the wire rod is controlled to enter a bainite phase region from a high-temperature austenite state at a cooling speed greater than or equal to 32 DEG C / s; the steel wire rod with a microscopic structure comprising tempered bainite and ferrite is prepared through isothermal tempering, toughening and destressing treatment, carbide precipitation control and roller way cover opening and slow cooling, so that generation of deteriorated structures such as martensite can be avoided, the structure state can be effectively adjusted, strong plasticity matching of the steel wire rod is achieved, and the service life of the steel wire rod is prolonged. And the tensile strength is 1120-110MPa, the percentage reduction of area is 63-67%, and the steel is suitable for the application fields of manufacturing 1200MPa-grade high-strength tool steel and the like, and is favorable for being directly processed into tool parts after being subjected to cold processing molding.

The invention relates to a hot-rolled wire rod for a 2100MPa-grade stranded wire and a manufacturing method thereof, after a high-carbon and high-silicon component system is rolled and spun into a wire rod, the wire rod is cooled at a cooling speed of more than or equal to 31 DEG C / s through online molten salt sorbite regulation and control treatment, and enters a sorbite phase region from an austenite state; the method comprises the following steps of: forming a structure mainly comprising a sorbite structure, performing isothermal tempering, promoting fusing of a part of sorbite lamellas, and finally performing roller way cover opening and slow cooling to prepare the hot-rolled wire rod of which the microscopic structure comprises a mixed structure consisting of tempered sorbite, tempered ferrite and fused sorbite, so that alloy components can be simplified, and the strong plasticity matching and the structure uniformity of the wire rod can be improved; the tensile strength is 1420-1470 MPa, the percentage reduction of area is 36%-41%, the composite material is used for the application field of manufacturing 2100 MPa grade stranded wires and the like, off-line heat treatment can be avoided, and the risk of wire breakage during downstream drawing and twisting is reduced.

The invention relates to a high-strength complex-phase hot-rolled wire rod for a 2200MPa-grade stranded wire and a manufacturing method of the high-strength complex-phase hot-rolled wire rod, and the manufacturing method comprises the following steps: rolling and spinning to form a wire rod by adopting a high-hardenability component design, and then carrying out online molten salt mixed phase region quenching isothermal treatment, so that the wire rod is firstly subjected to front-section molten salt treatment and enters a bainite and pearlite phase region from an austenite state; the method comprises the following steps: carrying out high-temperature treatment on austenite to promote part of austenite to be converted into bainite and sorbite, carrying out later-section molten salt treatment, increasing the molten salt temperature, reducing the molten salt circulation amount, promoting unconverted retained austenite to be decomposed and converted into bainite and sorbite, carrying out isothermal tempering, and finally carrying out slow cooling through a roller way, the hot-rolled wire rod with a microscopic structure comprising a complex phase structure composed of tempered bainite and tempered sorbite is prepared, the material cost can be reduced, the complex phase structure and the structure toughness can be regulated and controlled on line, the tensile strength is 1505-1555 MPa, the percentage reduction of area is 32%-37%, efficiency and energy consumption are both considered, off-line heat treatment is avoided, and high-efficiency production of stranded wires is promoted.

The invention relates to a high-strength complex-phase hot-rolled wire rod for a 2360MPa-grade stranded wire and a manufacturing method of the high-strength complex-phase hot-rolled wire rod. After a Mo-V high-carbon component system is rolled and spun into a wire rod, the wire rod is subjected to on-line molten salt weak quenching toughening treatment, so that the wire rod is subjected to front-section molten salt treatment to be quickly cooled, enters a bainite and sorbite mixed phase region from an austenite state, and is subjected to high-temperature heat treatment to form a high-strength complex-phase hot-rolled wire rod; the method comprises the following steps: firstly, carrying out heat treatment on residual austenite to form a structure mainly comprising bainite and sorbite, then carrying out later-section molten salt treatment, increasing the temperature of molten salt, promoting decomposition and conversion of unconverted residual austenite into sorbite, carrying out isothermal tempering, and finally, carrying out roller way slow cooling to prepare a hot-rolled wire rod of which the microscopic structure comprises a complex-phase structure consisting of tempered bainite and tempered sorbite, the method has the advantages that the structure toughness can be regulated and controlled on line, the tensile strength is 1574-1627 MPa, the percentage reduction of area is 28-33%, the mechanical property fluctuation is reduced, the material cost and the production efficiency are both considered, the ultra-high-strength stranded wire can be produced without off-line heat treatment, and the wire breaking risk is reduced.

The invention relates to the technical field of high-performance ceramic preparation, in particular to a partial pressure sintering method of a silicon nitride ceramic chip, which comprises the stages of charging, negative pressure degreasing, partial pressure sintering, pressure sintering and rapid cooling: during charging, charging a green body containing a silicon nitride raw material and Y2O3 and MgO auxiliaries into a furnace, and exhausting air; in the negative-pressure degreasing stage, low-pressure nitrogen and staged heating are used for promoting formation and volatilization of an auxiliary liquid phase; volatile matters are released through stepped nitrogen partial pressure in the partial pressure stage; in the pressurizing stage, gradient increase of pressure from low pressure to 35 bar is achieved through phase change buffering, high-temperature densification, ultra-high-temperature homogenization and slow cooling, and precise pressure control is achieved by combining dynamic pressure-static pressure mode switching; according to the method, the problems of cracking, uneven density and the like of a traditional process are effectively solved, the ceramic chip yield and the dimensional precision are improved, the microstructure and the mechanical property are optimized, the high-temperature applicability and the thermal property are enhanced, meanwhile, the use amount of auxiliaries is reduced, energy consumption is reduced, and practicability and economical efficiency are achieved.

The invention relates to the technical field of HB450-grade thick-specification wear-resistant steel plates, in particular to a flame cutting delayed crack-free HB450-grade thick-specification wear-resistant steel plate and a production method thereof. The steel is composed of the following chemical components in percentage by weight: 0.18%-0.22% of C, 1.00%-1.10% of Si, 0.8%-1.0% of Mn, 0.015%-0.03% of Nb, 0.6%-0.70% of Cr, 0.06%-0.09% of Al, 0.0005%-0.0020% of B, more than or equal to 1.4% and less than or equal to 1.6% of Mn and Cr, and the balance of Fe and inevitable impurities. The production process flow comprises the steps of smelting, refining, slab continuous casting, casting blank heating and slow cooling, slab heating, controlled rolling, stacking and slow cooling, quenching and tempering heat treatment, flame cutting with temperature and slow cooling with hot water. The surface hardness is larger than or equal to HB450, the thickness ranges from 40 mm to 80 mm, the tensile strength is larger than or equal to 1250 MPa, the retained austenite content is 5%-7%, delayed cracks do not exist after fire cutting, the trimming hardness is larger than or equal to HB410, AKV at the temperature of-40 DEG C is larger than or equal to 40 J, and A is larger than or equal to 12%.

The invention relates to the technical field of ceramic intelligent manufacturing, in particular to a ceramic firing process thermal deformation intelligent prediction and self-adaptive temperature precise regulation and control system, which comprises a multi-source sensing module (a thermal infrared camera array, a temperature sensor, a laser displacement meter and a powder characteristic analyzer); a hybrid prediction model (a space-time convolutional neural network constrained by a physical mechanism); and the self-adaptive temperature control actuator comprises a partitioned burner group, a quenching / slow cooling pipeline and a gas-air volume decoupling controller. According to the scheme, through a multi-mode perception-hybrid modeling-dynamic optimization full-process closed-loop architecture, the single-point technical limitation of existing patents is broken through, and the zero-defect precise manufacturing target of ceramic firing is achieved.

The invention relates to the technical field of high-hardness thick-specification high-wear-resistance steel plates, in particular to a high-hardness 30-80mm thick-specification flame-cutting-delayed-crack-free high-wear-resistance steel plate and a production method thereof. New flame cutting delayed crack preventing components and process design are adopted, the chemical components of the steel plate are mainly characterized by medium carbon, high silicon and niobium microalloying, and the wear-resistant steel plate with low impurity content, uniform and fine martensite and a certain amount of retained austenite structures is obtained after refining, continuous casting, controlled rolling and heat treatment. And formation and expansion of delayed cracks during flame cutting can be inhibited. And during flame cutting, thermal stress and structural stress formed in the cutting process of the thick steel plate are reduced through the cutting process of cutting with temperature and slow cooling with hot water after cutting, and the effect of no delayed crack after cutting is achieved. The surface hardness is larger than or equal to HB500, the tensile strength is larger than or equal to 1350 MPa, AKV at-40 DEG C is larger than or equal to 30 J, A is larger than or equal to 10%, retained austenite is 4%-6%, delayed cracks do not exist after flame cutting, and the flame cutting edge hardness is larger than or equal to HB460.

The invention relates to a 1300 MPa-grade high-strength tool steel wire rod and a manufacturing method thereof, after a Cr-Nb-V medium carbon component design is adopted for rolling and spinning to form a wire rod, the wire rod is subjected to online molten salt micro-quenching tempering treatment, the wire rod is controlled to enter a lower bainite phase region from a high-temperature austenite state at a cooling speed greater than or equal to 31 DEG C / s, and a quenching structure mainly comprising quenching bainite is formed; the steel wire rod with a microscopic structure comprising tempered bainite and ferrite is prepared by carrying out isothermal tempering and toughening destressing treatment on a quenched structure and finally carrying out roller way slow cooling, so that the material cost can be properly controlled, the strength and plasticity matching of the steel wire rod is improved, the tensile strength is 1255-1305MPa, and the percentage reduction of area is 58-63%, so that the steel wire rod can be directly processed into a part after being subjected to cold processing molding, and the service life of the steel wire rod is prolonged. And tool steel production energy consumption, cost reduction and efficiency improvement are facilitated.

The invention belongs to the field of dies, and particularly relates to a cam cover die-casting die with a spiral cooling structure, a die table mechanism comprises a lower die table and an upper die table which are combined, and a lower die core and an upper die core which are matched with each other are arranged in the lower die table and the upper die table; the pouring mechanism comprises a pouring end seat arranged on the upper mold table, a pouring channel penetrating through the upper mold core is formed in the pouring end seat, and the other end of the pouring channel penetrates into a closed cavity of the lower mold core and the upper mold core; the track mechanism comprises a track table arranged on the outer side of the cavity; the multi-layer structure of the spiral pipe is in direct contact with the outer wall of the cavity, the spiral flowing path of a cooling medium is combined, the heat exchange area and cooling uniformity are increased, the casting deformation risk is reduced, a temperature sensing end base integrated temperature sensor monitors the temperature of the cavity in real time, and the flow of the cooling medium is dynamically adjusted in cooperation with a deformation piece driven by an air bag piece. And intelligent control of slow-cooling anti-cracking in a high-temperature area and rapid-cooling shaping in a low-temperature area is realized.

The invention discloses a wire rod for 2000MPa-level prestressed steel with the large specification of 15mm and a preparation method of the wire rod, and belongs to the technical field of metal material preparation and metal pressure processing. The invention aims to develop a 15mm large-specification high-performance prestressed steel wire rod with a novel component system and a matched production process thereof, the tensile strength of the wire rod is greater than or equal to 1200MPa, and the percentage reduction of area (after aging) is greater than or equal to 30%; the product can be used as a large-specification high-strength high-speed rail plate prestressed steel wire and a 1960-2000MPa-grade high-performance prestressed steel wire and a steel strand. According to the method, the technological process of molten iron pretreatment, converter smelting, LF refining, RH refining, square billet continuous casting, casting billet slow cooling pit slow cooling, casting billet heating, high-pressure water descaling, controlled rolling and controlled cooling and PF line heat preservation channel slow cooling and a complete and controllable production process system are adopted; and the harsh requirements of large-size high-performance prestressed materials of modern important projects on the performance of the wire rod are met.

The invention discloses a long glass fiber compression molding method and system, and the method comprises the steps: laying a continuous glass fiber plate and a long glass fiber material ball in a mold cavity in a partitioned manner, and obtaining a positioned composite green body; local prepressing is applied to the interlocking area of the composite blank, a mechanical meshing structure is formed, and a prefabricated body with an interface interlocking structure is obtained; establishing a pressure distribution model according to the geometric characteristics of the product to obtain differentiated pressure parameter combinations; placing the preform in a heating mold, and applying pressure in stages according to the pressure parameter combination to obtain a semi-finished product without glass fiber exposure; and for the semi-finished product, under the state that the second pressure value is kept, rapid cooling is conducted on the flange and the corner area, slow cooling is conducted on the large face area, and a final product with the balanced internal stress is obtained. By utilizing the embodiment of the invention, the efficient synergy of the continuous glass fiber plate and the long glass fiber material block can be realized, and the mechanical property and the structural integrity of the product are improved.

The invention belongs to the technical field of steel forging, and particularly relates to martensite heat-resistant steel and a forging method. A forging process is optimized and improved, and after forging, furnace cooling of a forge piece is changed into the mode that the forge piece is rapidly cooled in air to 30-50 DEG C above the Ms transition point firstly, and then the forge piece is put into a furnace to be cooled along with the furnace. And coarse carbides generated during slow cooling of the material in a high-temperature area are avoided, then the material is put into a furnace to be cooled along with the furnace, and the forge piece is prevented from cracking during rapid cooling at the Ms point and below the Ms point. In the forge piece heat treatment process, the quenching charging mode is changed from furnace heating to temperature charging, the forge piece heating rate is increased, the superheat degree in the material austenitizing process is increased, the nucleation rate is promoted to be increased, and the grain size of the quenched forge piece is effectively increased. And the second tempering cooling mode is changed from air cooling to oil cooling. And the generation of second-class tempering brittleness in the tempering process is effectively avoided. A plurality of batches of forgings are produced according to the optimized process scheme, the impact performance tends to be stable, and the situation that the accidental impact performance is unqualified does not occur any more.

The invention discloses a selective laser melting high-temperature preheating device with high-precision temperature control. The selective laser melting high-temperature preheating device comprises a laser; a forming cylinder; the piston is arranged in the forming cylinder in a lifting manner; the mounting plate is arranged on the piston, and a first accommodating groove is formed in the top surface of the mounting plate; the heating plate is arranged in the first accommodating groove and is provided with a heater; the forming base plate is arranged above the heating plate and is provided with a temperature sensor; the cooling mechanism is used for cooling the piston, the mounting plate, the heating plate and the forming base plate; a heat insulation plate is arranged between the bottom wall of the first containing groove of the installation plate and the heating plate. The invention further discloses a selective laser melting high-temperature preheating method with high-precision temperature control. Through the mode, the problem of cracking caused by overlarge temperature gradient in the SLM forming process is solved, the problems of low preheating temperature, low cooling speed and inaccurate temperature control of the formed substrate are also solved, the powder laser absorptivity can be improved to a certain extent, the scanning speed is increased, and the production efficiency is improved.

The invention relates to the technical field of welding processing equipment, and discloses a positioning welding tool for processing a solar photovoltaic support, the positioning welding tool comprises a base, a sealing cover is arranged on the base, and a sealed processing space is formed in the sealing cover and the base; and the opening door is arranged in the middle of one side of the sealing cover and used for a worker to feed in the photovoltaic support before machining and take out the photovoltaic support after machining is completed. By adding and arranging the preheating and slow cooling mechanism, before the solar photovoltaic bracket is welded, the mechanism uniformly preheats the welding end part of the bracket, so that the binding force between a zinc coating and a base material is weakened under the thermal action, and the subsequent efficient removal of the zinc coating on the surface of the bracket is facilitated; meanwhile, base material damage or zinc layer residue caused by forced stripping is avoided, the internal stress of the material can be preliminarily released in the preheating process, the deformation risk caused by shock heating in the welding process is reduced, and the geometric stability of the support structure in the machining process is ensured.

The invention discloses a forming process of a steel lining polytetrafluoroethylene concentric reducing pipe. The forming process comprises the following specific steps that S1, pretreatment is conducted, specifically, after a steel pipe is cut, laser rust removal is conducted, and primer containing a silane coupling agent is sprayed on the surface; s2, powder filling is conducted, specifically, a mold is placed in the center of the steel pipe, and then PTFE-containing powder is added into modified powder according to 1.3 times of the volume between the steel pipe and the mold; the steel pipe enters a sintering area after the temperature of the steel pipe reaches 200 DEG C in a preheating area, PTFE powder is melted at the temperature of 380 DEG C and is subjected to roll coating forming, gradient cooling is conducted in a slow cooling area at the speed of 5 DEG C / min, the temperature is stabilized at 260 DEG C, internal stress is eliminated, an electromagnetic induction coil is arranged in the preheating area, and microwave heating is adopted in a forming area; s4, static pressure forming; s5, reducing forming is carried out; and S6, post-treatment. The forming process of the steel lining PTFE concentric reducing pipe has the effects that the phenomenon that the lining layer is cracked or stripped after cooling is avoided, and the yield is increased.

The invention discloses a novel process for realizing online softening and improving cold heading performance of SCM435 series cold heading steel, and relates to the technical field of cold heading steel processing. The invention discloses a novel process for realizing online softening and improving the cold heading performance of SCM435 series cold heading steel. According to the method, S1, steel billet continuous casting forming, S2, steel billet precise heating, S3, low-temperature rolling molding, S4, wire rod standard spinning, S5, stelmor cooling and S6, heat preservation vestibule slow cooling are carried out, the uniformity of the process performance is remarkably improved, by innovatively optimizing the spinning coefficient and the roller way speed, it is fundamentally guaranteed that the disc shape is neat, the heat dissipation conditions of all positions of the wire rod in a slow cooling vestibule are consistent, and the heat dissipation efficiency of the wire rod is improved. Therefore, uniform transformation of a whole-roll structure and a same-circle structure is achieved, the consistency of cold heading performance is greatly improved, the cracking risk in the cold heading process is effectively reduced, the technology is remarkable in energy-saving and consumption-reducing effect, rolling waste heat is fully utilized for on-line softening, the traditional off-line reheating and annealing procedure is completely omitted, and energy consumption can be saved by about 30% or above.

The manufacturing method comprises the following steps: rolling and spinning high-carbon and high-silicon components of Nb-Mo to form a wire rod, and then carrying out online molten salt strong isothermal toughening treatment, so that the wire rod is firstly subjected to front-section molten salt treatment and is rapidly cooled, and enters a sorbite phase region from an austenite state to form a structure taking a sorbite structure as a main structure; and then carrying out rear-section molten salt treatment, reducing the circulation volume of molten salt, promoting the unconverted retained austenite to be continuously converted into sorbite, carrying out isothermal tempering, promoting fusing of a part of sorbite lamellar layers, and finally carrying out slow cooling through a roller way, so as to prepare the hot-rolled wire rod of which the microscopic structure comprises a mixed structure consisting of tempered sorbite, ferrite and fused sorbite, according to the invention, abnormal tissues can be inhibited, the tensile strength is 1566-1616 MPa, the percentage reduction of area is 33%-38%, and the production efficiency is considered, so that the ultrahigh-strength stranded wire can be produced without off-line heat treatment, and the risk of wire breakage is reduced.

A preparation method of the outdoor high-strength polyester fiber with the radiation refrigeration function comprises the following steps that titanium dioxide, silicon dioxide, silicon carbide and zirconium phosphate are blended and ground in proportion and then dispersed in an acetone solution, a dispersing agent is added, and nano-particle dispersion liquid is formed through ultrasonic treatment; mixing the nano-particle dispersion liquid with the polyester chips; feeding the mixed composite material into a screw extruder for melt blending to form a spinning solution; after being accurately metered by a metering pump, the spinning solution is extruded by a spinneret plate to form fiber tows, and the spinneret plate is provided with a slow cooling and heating device; and performing post-treatment on the fiber tows to obtain the high-strength polyester fibers. According to the invention, a specific combination of titanium dioxide, silicon dioxide, silicon carbide and zirconium phosphate is selected, and a specific slow cooling technology and high-power stretching shaping are matched, so that the fiber has excellent radiation refrigeration performance and mechanical strength, and can be widely applied to the fields of outdoor clothing, awning cloth, car clothing and the like.

The invention provides a vertical position welding method for bridge steel. The vertical position welding method comprises the steps that 1, a groove is manufactured, specifically, the X-shaped groove without a truncated edge is manufactured in a vertical position mode through a flame cutting technology; and the groove is polished and derusted according to requirements. 2, preheating, wherein the bridge steel is preheated to 75 DEG C in an electric heating mode; and 3, welding, wherein solid welding wire argon-rich mixed gas shielded welding is adopted for vertical position welding. And 4, post-weld heat treatment is conducted, specifically, after welding is completed, post-heat treatment is conducted at 200-250 DEG C through a crawler-type heater, and slow cooling is conducted to the room temperature after heat preservation is conducted for 3 hours. By researching and developing a welding material and a welding process matched with the Q890qE high-strength bridge steel, the technical problem of quality of a Q890qE vertical position butt welding seam is solved. Welding forming is stable, efficiency is high, deformation is small, the appearance is good, strength and weather resistance are balanced, the service life is long, and economical efficiency and environment friendliness are both considered; the method is especially suitable for engineering scenes with strict requirements on strength, toughness and durability such as long-span bridges and alpine region bridges, and has remarkable economic advantages and social value.

The invention discloses a production method of a low-cost carbon spiral spring steel wire rod, the chemical components of the steel grade do not contain precious alloy elements, the production process comprises the steps of converter top and bottom combined blowing smelting, LF refining, 6 # small square billet continuous casting, slow cooling and rolling in a wire factory, and the use requirements of users can be met without VD refining furnace production.

The invention relates to the technical field of silica gel injection molding temperature control, in particular to a temperature control system and process for liquid injection molding of a silica gel toy. The process comprises the following steps: S1, according to three-dimensional model data of a silica gel toy, automatically identifying geometric feature information of the silica gel toy; s2, setting initial temperature parameters of each injection molding stage on the basis of the geometrical characteristic information in combination with physical characteristics of the liquid silica gel; s3, in the injection period, based on the initial temperature parameters, micro-heating / mold temperature maintaining / micro-cooling is conducted on different areas of the silica gel toy; s4, in the pressure maintaining period, when the liquid silica gel is filled to the preset filling proportion, the mold temperature of the multicolor injection molding material flow interface area is reduced to the freezing temperature; s5, in the main vulcanization period, a self-adaptive temperature adjustment strategy is executed on the thick-wall area and the thin-wall area; and S6, in the cooling and demolding period, a corresponding rapid cooling strategy / slow cooling strategy is executed on the thick-wall area and the thin-wall area. The size stability and the assembly precision of the complex thin-wall silica gel component are remarkably improved.

The invention discloses an on-line quenching production method for thick Q690D high-strength steel, which relates to the field of steel smelting, and comprises the following steps: producing the thick Q690D high-strength steel by adopting the steps of molten iron pretreatment, converter smelting, LF treatment, RH vacuum treatment, continuous casting, blank slow cooling, casting blank heating, rolling, on-line quenching and tempering treatment, and the thick Q690D high-strength steel comprises the following components: 0.14-0.18% of C, 0.25-0.35% of Si, 1.40-1.55% of Mn, less than or equal to 0.015% of P, less than or equal to 0.015% of S, less than or equal to 0.015% of P and the balance of Fe. The steel comprises the following components in percentage by weight: less than or equal to 0.004% of S, 0.38-0.46% of Cr, 0.18-0.23% of Mo, 0.025-0.035% of Nb, 0.01-0.03% of Ti, 0.0009-0.0022% of B, 0.02-0.04% of Al and the balance of Fe and inevitable impurities. By means of the method, low-cost production of the thick Q690D high-strength steel can be achieved.

A GH3044 high-temperature alloy laser welding method belongs to the field of laser welding technology and is suitable for welding thin-walled overlap structures. It can further improve the welding strength of the weld spot and achieve single-sided welding and double-sided forming. The method includes the following steps: sequentially pickling, alcohol cleaning, and drying the surface of the high-temperature alloy to be welded; fixing the high-temperature alloy to be welded on a laser welding turntable to control the welding gap; adjusting the height of the shielding gas and the inclination angle with the weld interface; programming to confirm the welding path, welding starting point, and preheating and slow cooling time; isolating the front and back surfaces of the workpiece to be welded from the air through inert gas during welding; and using a pulsed welding laser to weld the joint to be welded. The present invention adopts a laser pulse slow cooling welding method to overcome defects such as cracks, pores, and surface depressions in high-temperature alloy laser welded joints, and can effectively improve the reliability of high-temperature alloy laser welded joints.

The invention discloses a laser cutting machining method for a conductive copper-aluminum plate, and belongs to the technical field of laser cutting. The method comprises the following steps that firstly, a to-be-machined plate is placed on a machine body; secondly, a supporting frame on the machine body is started, and the supporting frame drives a laser head to move to the position above the plate for cutting; thirdly, a cooling assembly is started, and the cooling assembly cools the laser head in work; the cooling assembly conveys the cooled gas into the heat preservation part, and the heat preservation part conducts heat preservation and slow cooling on the plates on the two sides of the cutting position; fourthly, the plate to be cut is preheated through a preheating part, and the cutting stability is improved; fifthly, impurities on the plate are blown off through an air blowing assembly arranged at the tail end of the preheating part; through a fan pump and a cooling pipe in the cooling assembly, the working heat of the laser head is effectively taken away, the service life of the laser head is prolonged, the cutting precision is guaranteed, meanwhile, heated gas is used for providing a heat source for follow-up heat preservation and slow cooling and plate preheating, and energy recycling is achieved.

The invention discloses a production method of high-toughness NM500 wear-resistant steel. The steel comprises the following chemical components in percentage by weight: 0.25%-0.26% of C, 0.15%-0.25% of Si, 0.88%-0.95% of Mn, less than or equal to 0.010% of P, less than or equal to 0.002% of S, 0.25%-0.30% of Cr, 0.015%-0.022% of Nb, 0.008%-0.016% of Ti, 0.020%-0.050% of Alt, 0.0014%-0.0020% of B, less than or equal to 0.00015% of H, less than or equal to 0.0040% of N, less than or equal to 0.0015% of O and the balance of Fe and inevitable impurities. CEV is not more than 0.48%, and Pcm is not more than 0.34%. The process comprises the steps of KR deS, converter smelting, LF refining, RH vacuum degassing, continuous casting, heating, rolling, slow cooling and heat treatment. According to the produced NM500 wear-resistant steel plate, the thickness covers 6-25 mm, the surface hardness ranges from 480 HB to 520 HB, the yield strength is larger than or equal to 1300 MPa, the tensile strength is larger than or equal to 1600 MPa, the elongation is larger than or equal to 14%, and the requirements that cold bending is conducted with the 6a diameter being 90 degrees, and the impact Akv at the temperature of-40 DEG C is larger than or equal to 45 J are met.

The invention discloses a high-uniformity extra-thick 420MPa-grade maritime work steel plate for an extremely low temperature environment and a manufacturing method thereof, and belongs to the field of ferrous metallurgy. The steel plate comprises the following chemical components in percentage by mass: 0.03%-0.07% of C, 0.15%-0.35% of Si, 1.40%-1.70% of Mn, less than or equal to 0.002% of S, less than or equal to 0.010% of P, 0.015%-0.045% of Als, 0.03%-0.05% of Nb, 0.10%-0.30% of Cr, 0.010%-0.020% of Ti and the balance of Fe and inevitable impurities, and the carbon equivalent CEV is less than or equal to 0.36%. The manufacturing process comprises the steps of smelting, continuous casting, blank heating, controlled rolling, controlled cooling and stacking slow cooling. The thickness of the obtained steel plate is 50-100 mm, the yield strength is larger than or equal to 420 MPa, the impact energy at the temperature of-60 DEG C is larger than or equal to 200 J, the strength difference of the whole plate is smaller than or equal to 40 MPa, and the steel plate has high strength, high toughness, good weldability and high uniformity and meets the requirement for the deep and far sea extremely-low-temperature environment.

According to the filler wire welding method based on the composite laser, the first laser beam and the second laser beam which are different in wavelength can be irradiated to the welding seam of the to-be-welded aluminum alloy workpiece through the composite laser welding head, and light spots, acting on the to-be-welded aluminum alloy workpiece, of the two laser beams partially coincide or do not coincide; the two light spots are distributed front and back in the welding direction. When the light spot of the first laser beam is in the front and the light spot of the second laser beam is in the rear, the first laser beam can be used for preheating, so that the welding wire melting efficiency can be improved, the reflectivity of aluminum alloy to the second laser beam is reduced, and welding seam forming is improved. When the light spot of the first laser beam is in the rear and the light spot of the second laser beam is in the front, the first laser beam can be used for slowly cooling a welding pool / performing post-heat treatment on a welding seam, so that welding defects are reduced. It can be seen that the welding quality of the to-be-welded aluminum alloy workpiece is improved by means of characteristic cooperation and function complementation between the two kinds of lasers of different wave bands.