189 results about "Stress relaxation" patented technology

The invention discloses a cultural relic preventive protection method based on big data analysis, belongs to the technical field of cultural relic protection, and mainly aims to solve the technical problem that a complex damage mechanism caused by mutual coupling of torsional deformation and inclined deformation in cultural relic protection is difficult to accurately predict. A dual-mode deformation data stream is obtained through a multi-point sensor, accurate data alignment is achieved through millisecond-level time synchronization processing, and correlation characteristics between deformation modes are recognized by calculating a coupling strength coefficient through correlation analysis. And when the coupling strength exceeds a threshold value, determining a deformation propagation direction vector by combining a spatial interpolation method, and calculating an internal stress distribution field and positioning a stress concentration area by utilizing a finite difference method. High-frequency sampling tracking is carried out on the high-risk area, and a stress relaxation time constant and a creep coefficient are obtained. Accurate prediction and active protection of cultural relic deformation damage are realized.

The invention discloses a light-weight manufacturing method and system for a PET bottle for food packaging, particularly relates to the technical field of PET bottle blank manufacturing, and aims to solve the problem that the subsequent blow molding quality is affected due to the fact that complex internal stress is generated in a bottle blank due to a rapid cooling process after injection molding in the prior art. Image information and temperature distribution data of a bottle blank after injection molding are obtained, geometric features and cooling rate differences are analyzed and recognized based on multi-physics coupling, a stress cause weight evaluation model is established to generate a stress distribution map, and then structural entropy increase factors under different temperature adjustment paths are simulated and calculated according to thermodynamic parameters, so that the temperature adjustment precision is improved. And carrying out partitioned temperature adjustment treatment on the bottle blank, and finally, carrying out constant-temperature and constant-humidity standing to sufficiently relax the stress. The internal stress distribution of the bottle blank can be effectively controlled, and the wall thickness uniformity and the mechanical property consistency of the light-weight PET bottle are improved.

The invention provides a data processing method and system based on intelligent construction, and relates to the technical field of intelligent construction.The method comprises the steps that viscosity, a temperature peak value, temperature and humidity and time delay distortion data in the solidification stage are collected in real time in the concrete pouring construction process, and a material stress relaxation model is constructed to calculate three-dimensional stress distribution; meanwhile, mapping sound wave time delay distortion data into a spatial topological graph, and extracting propagation anomaly features by using a space-time graph convolutional network; and generating a crack risk distribution diagram by fusing stress distribution and abnormal characteristics, and finally, accurately positioning a potential defect area according to risk gradient change. The early warning capability of concrete construction quality defects is improved.

The invention discloses an invasion limit surrounding rock excavation method for a large deformation section of soft rock, and relates to the technical field of invasion limit surrounding rock excavation construction for the large deformation section of the soft rock. The invasion limit surrounding rock excavation method for the large deformation section of the soft rock comprises the steps that refined partitioning of an invasion limit body is achieved through dense scanning and loose circle testing; dividing the invasion limiting body into a core pressure-bearing area and a peripheral stress relaxation area; a main stress diversion arch crossing an invasion limit section is constructed through full-ring radial grouting reinforcement and erection of a strong profile steel temporary cover arch, and effective stress transfer is achieved; the mode of subarea gradual type dismantling and chiseling and instant supporting is adopted, a peripheral stress relaxation area is treated firstly, then a core pressure-bearing area is treated, and surrounding rock disturbance is reduced; the circumferential stress equalization is realized by compensating grouting in stages and dynamically adjusting the grouting pressure according to real-time monitoring data. According to the method, the excavation construction safety of the invasion limit surrounding rock of the large deformation section of the soft rock can be improved, surrounding rock disturbance is reduced, stress distribution is optimized, and the treatment efficiency of the invasion limit surrounding rock is improved.

The invention discloses a heavy-duty gas turbine blade creep fatigue life design method considering an anisotropic effect, and relates to the technical field of gas turbine key component creep fatigue life evaluation.The method comprises the steps that orientation factor parameters on characteristic orientation are determined based on tensile data on [001] crystal orientation; constructing a modified stress relaxation formula; constructing an anisotropic failure strain energy density equation based on the pure creep performance data and the orientation factor parameters, and determining an upper platform of failure inelastic strain energy density on [001] crystal orientation; further determining an upper platform of the failure inelastic strain energy density on the feature orientation; constructing a creep damage prediction model based on a modified stress relaxation formula and an anisotropic failure strain energy density equation; and adopting the creep damage prediction model to obtain the creep fatigue life of the anisotropic turbine blade material sample. The method meets the actual requirements of service life evaluation of the high-temperature part of the heavy-duty gas turbine.

The invention provides an intelligent temperature control method and system for relieving stress of a glass annealing kiln. The method comprises the following steps: transmitting acoustic surface waves through a distributed sonic sensor to collect stress propagation data in glass, decoupling coupling characteristics of sound velocity and temperature, extracting a relaxation time constant, and generating a stress relaxation rate; performing time difference cross-correlation analysis to construct a stress propagation three-dimensional gradient field, establishing an incidence relation between the relaxation rate and the gradient field, and constructing a mapping strategy of the temperature set value and the relaxation rate according to the incidence relation; generating a dynamic temperature adjusting parameter and converting the dynamic temperature adjusting parameter into a heater power control signal; and dynamically adjusting a stress data feature extraction rule to match a real-time stress state according to the relevance between the gradient field update frequency and the temperature adjustment rate. According to the application, dynamic mutual optimization of the annealing stress elimination efficiency and the kiln temperature setting precision is realized, the glass residual stress is reduced, and the hidden danger of plate explosion is eliminated.

The invention discloses a manganin current sampling on-line self-correction method and system of an intelligent fusion terminal. The method and system are applied to the intelligent fusion terminal comprising a manganin diverter assembly. The assembly comprises a working resistor connected in series in a main current loop and a reference resistor for monitoring, the working resistor and the reference resistor are thermally coupled, and the reference resistor does not bear working current during normal sampling. The method comprises the following steps: respectively measuring real-time resistance values of the two resistors in a silent working window period; calculating a current actually measured resistance value ratio; obtaining an ideal resistance value ratio of the two in a stress relaxation-free ideal state; obtaining a correction resistance value ratio variable quantity according to a difference value between an actual measurement ratio and an ideal ratio; and finally, calculating a correction coefficient and updating a sampling channel parameter so as to compensate resistance drift caused by long-term electric thermal stress and realize automatic correction of subsequent current sampling. According to the method, on-line and high-precision self-correction independent of an external reference is realized, and the problem of long-term stress relaxation of a manganese-copper material is effectively solved.

An optical component including: a substrate on which an optical element is mounted; a transparent sealing member disposed above the substrate and configured to seal the optical element; and a bonded portion in which a plurality of metal films are laminated, and which is configured to bond the transparent sealing member and the substrate. The bonded portion includes: one or more stress relaxation layers constituted by one or more metal films having a Young's modulus of less than or equal to 150 GPa, the one or more stress relaxation layers having a total thickness of greater than or equal to 1.2 μm; and a diffusion prevention layer disposed on each of both sides in a thickness direction of each of the one or more stress relaxation layers, and configured to prevent diffusion of metal constituting the stress relaxation layer.

The invention relates to the technical field of material performance test devices, in particular to a low-temperature tensile test device for an insulating material. The problems that an existing low-temperature stretching tool is poor in clamping and fixing effect on an insulating material in the nuclear fusion field, a sample is prone to torsion sliding in a test, stress relaxation is generated, and adaptability is insufficient are mainly solved. According to the technical scheme, the testing device comprises a clamp, a loading controller, a loading rod, a tensile sample, a force sensor, a supporting device, a testing machine reaction frame and a low-temperature environment box; the clamp comprises an upper clamp and a lower clamp; the low-temperature environment box is arranged outside the testing machine reaction frame, and the supporting device is installed outside the low-temperature environment box. According to the test device, stable positive pressure is applied to a sample, torsion sliding and stress relaxation are prevented, it is ensured that the stretching position of the sampled sample is stable and free of errors, the test failure rate is reduced, the qualification rate is increased, the clamp structures are the same, the pressing blocks are detachable, and universality and efficiency are improved.

The present application relates to the technical field of liquid rocket engine nozzle, and discloses a manufacturing method of an extension section of a large-scale liquid rocket second-stage engine nozzle, which is characterized in that the extension section is divided into n cylinder sections according to the size of the plate and the elongation rate of the plate, and each cylinder section is divided into m melon pieces to be prepared by means of tailor welding; the number n of the cylinder sections ensures that the number of the girth welds of the extension section is the least, and the welding of the girth welds is maximally avoided; the cylinder sections of the extension section are obtained by stress relaxation heat correction treatment of preformed cylinder sections, and the uncontrollable welding deformation problem is overcome. The present application solves the problem that the uncontrollable deformation caused by the springback of the sheet metal forming in the block welding leads to the difficulty in guaranteeing the profile tolerance of the inner surface of the nozzle extension section, improves the welding quality, reduces the rejection rate and production cost of the finished product, improves the production efficiency, has a wide application prospect, and any large-diameter thin-walled product can be processed according to the method of the present application.

The present invention relates to: an optical component (10) obtained by bonding a transparent sealing component (14) to a substrate (44) on which an optical element (12) is mounted, thereby sealing the optical element (12); the transparent sealing component (14); the substrate (44); and a method for producing the optical component (10).According to the present invention, each metallized layer (24, 46) that bonds the transparent sealing component (14) and the substrate (44) is provided with: one or more stress relaxation layers (30), each composed of a metal film having a modulus of elasticity of 150 GPa or less and having a total thickness of 1.2 µm or more; and diffusion prevention layers (28, 32) arranged on both sides of the stress relaxation layers (30) in the thickness direction, which prevent the diffusion of a metal from which the stress relaxation layers (30) are composed.

The invention provides a method for analyzing time-history stress relaxation of anchoring force of a pre-stressed anchor cable under high-pressure stress, and relates to the technical field of geotechnical engineering. According to the method, engineering geological investigation, ground stress testing and indoor triaxial rheological testing are systematically combined, a potential high-stress area is accurately recognized, key rheological parameters of a rock-soil body are obtained, and then the stress self-adaptive creep coupling constitutive model with the long-term strength of the rock body as the criterion is constructed; and finally, accurately predicting the time-history creep strain of the rock-soil body and the anchoring force loss of the anchor cable under the high stress condition through numerical calculation. According to the method, the defect that a traditional creep theory describes a nonlinear creep behavior in a high-pressure stress state and a prestress loss coupling mechanism is effectively overcome, and the prediction precision and reliability of mechanical response of an anchoring system are remarkably improved; a basis is provided for long-term stability evaluation and safety control of prestressed anchoring engineering under complex geological conditions, and geotechnical engineering anchoring design and safety early warning are developed towards the refined and intelligent direction.

The present invention provides a laminated structure which is suitable for the manufacture of a printed board and which can suppress peeling of a wiring pattern when a bending stress is applied to the printed board. A laminated structure includes a resin base material and a metal layer provided on a first surface of the resin base material, the resin base material having a recessed portion which opens on the first surface and an inner surface of the recessed portion having a stress relaxation structure, a portion of the metal layer extending into the recessed portion.

The invention relates to a metal material strain rate effect measurement method based on multiple stress relaxation, which comprises the following steps: carrying out a standard quasi-static stretching or compression test on a material sample at a constant strain rate to obtain a stress-strain curve; analyzing a strain range according to a stress-strain curve, and determining a stress relaxation frequency N to be developed and a corresponding relaxation strain value sequence epsilon i, i = 1... N; a material sample is taken to be subjected to a tensile or compression test at a set strain rate, stress relaxation lasts for relaxation time delta t when the strain sequentially reaches values in each relaxation strain value sequence, and after each stress relaxation, the tensile or compression test is performed according to the set strain rate; obtaining a stress-plastic strain rate curve corresponding to each relaxation strain epsilon i; and obtaining a stress-strain curve corresponding to each strain rate. Stress-strain curves corresponding to different plastic strain rates in a quasi-static range can be obtained through a single sample.

The invention relates to the technical field of rubber product processing control, and discloses a control method and system for a sealing ring automatic production line, and the control method for the sealing ring automatic production line comprises the steps: constructing an equipment reference resistance curve in a no-load state; the servo press is controlled to execute a micro-speed steady-state exhaust sequence, and the position locking state is maintained at the closed tail end; calculating a net rheological torque in combination with the reference curve, and extracting a contact displacement drift amount, an in-situ vulcanization rate index and a stress relaxation rate; according to the parameters, the filling stability and the rubber material rheological state are judged, and a process correction instruction is generated. According to the method, physical and chemical characteristics are accurately decoupled from servo torque signals through a micro-speed test and position locking mechanism, closed-loop control over foreign matter risks, filling quality and vulcanization degree is achieved through multi-dimensional parameters, and the problem of quality instability caused by rubber fluctuation in sealing ring production is effectively solved.

The present invention provides an acoustic sensor that can suppress a decrease in sensitivity. [Solution] The device comprises a support body 10, a support region 21a placed on and supported by the support body 10, and a vibration region 22 connected to the support region 21a and capable of vibration, and a vibration unit 20 that outputs a detection signal according to the deformation of the vibration region 22. The support body 10 has a recess 10a formed in the portion facing the vibration region, the vibration region 22 has a portion that is subjected to compressive stress, and the vibration unit 20 has a stress relaxation hole 81.

The invention provides a parallel rheological framework constitutive model parameter calibration method for high-density polyethylene, and the method comprises the steps: obtaining the stress-strain data of a relaxation and rebound test, picking the stress-strain data at the relaxation end moment and the rebound completion moment, and then stripping time-independent elasticoplastic deformation behaviors, thereby achieving the calibration of the parameters of the parallel rheological framework constitutive model. Determining elastic-plastic parameters of the constitutive model of the parallel rheological framework; then, combining curve fitting of axial tension data and elasticoplastic deformation data to ensure that parameters of an elasticoplastic layer of the parallel rheological frame can be really matched with time-independent mechanical characteristics of a sample piece to be tested; and then loop optimization is carried out on viscoelastic layer parameters by using a second-generation non-dominated sorting genetic algorithm, and a simulation result is quantitatively judged through an equivalent root-mean-square error, so that the suitability of the parameters in stress relaxation and creep scenes is ensured, and finally, efficient and accurate calibration of the constitutive model parameters is realized.

The invention relates to the technical field of gear machining, and discloses an internal gearing powerful gear honing tooth surface residual stress field calculation method based on force-heat coupling. The method comprises the following steps: establishing a honing motion coordinate system to calculate three-dimensional coordinates and relative speed of a contact point, and constructing a three-dimensional to two-dimensional coordinate mapping mechanism; constructing a tooth surface temperature field model based on the relative speed, the correction of heat taken away by cuttings and the point heat source superposition principle; respectively solving mechanical and thermal load stress fields based on the two-dimensional coordinates and the temperature field, and superposing to obtain total elastic stress; and an elastic-plastic constitutive relation and a yield criterion are introduced, stress relaxation calculation is performed through a step-by-step unloading method and a plastic release stress balance equation, and the final residual stress is obtained. The method solves the problems of lack of force-heat coupling mechanism analysis and insufficient stress evolution calculation precision in the prior art, and realizes accurate prediction of the internal meshing gear honing residual stress.

A paste extrusion die comprises a cylinder barrel, a cylinder barrel nut, a sealing ring assembly and a lower die, the cylinder barrel is fixed to the lower die, an extrusion inner cavity of the lower die sequentially comprises a feeding section, a circular deformation section, a stress relaxation section, a film release expansion section, a flat deformation section and a discharging section, and the sealing ring assembly is arranged at the front end of the feeding section. Extrusion cavities in the left die and the right die of the lower die are symmetrically designed; the sealing ring assembly comprises a sealing ring supporting ring, an air bag, an inflation hole and a sealing ring. The air bag is in extrusion fit with the end face of the sealing ring through inflation. According to the extrusion die disclosed by the utility model, the runner between the cylindrical blank body feed port and the flat base band discharge port is integrally designed, and the extrusion inner cavity is designed, so that the flat base band is consistent in density and high in film strength, and the surface quality of the base band is optimized.

This invention relates to a performance testing method for a high-load-bearing, long-stroke air spring assembly, comprising the following steps: S1, determining the model and operating parameters; S2, installation and alignment; S3, air pressure setting; S4, pre-cycle; S5, stretching the air spring; S6, compressing the air spring; S7, unloading and returning; S8, recording deformation data. Before formally recording data, the performance testing method of this invention performs multiple complete compression and rebound pre-cycles on the air spring. This not only eliminates the initial structural stress relaxation of the air spring bladder and cord layer, improving the repeatability and consistency of stiffness testing, but also identifies hidden damage or assembly defects in the air bladder in advance, avoiding sudden failure during formal testing. Furthermore, it allows the rubber material of the air spring to reach a stable hysteresis working state, simulating the actual pre-service break-in process, making the subsequently measured stiffness parameters closer to the true values ​​of long-term stable operation, and thus making the test data more accurate.

The glass-based article includes a stress profile for providing improved drop performance. A glass-based substrate includes a glass transition temperature (Tg), a liquid brittleness index (m), and a hypothetical temperature (Tf), where Tg is less than or equal to 650 DEG C, a value obtained by subtracting Tg from Tf is greater than or equal to-30 DEG C, and m is greater than or equal to 25. The stress relaxation rate is greater than or equal to 10%, 20% or greater. An article may include a lithium-based aluminosilicate composition and a fracture toughness of greater than or equal to 0.75 MPa * m < 0.5 >. The stress profile includes: a spike region extending from the first surface to an inflection point; and a tail region extending from the inflection point to a center of the glass-based article, the tail region comprising: a negative curvature region in which a second derivative of a function of stress and depth is negative; a depth of compression (DOC) greater than or equal to 0.22 t, and a parabolic region originating at the DOC and extending to a center of the glass-based article.

The invention belongs to the technical field of industrial automation control, and particularly discloses and provides a soft bed production stacking intelligent control system which is characterized in that a double-field collaborative distribution diagram containing structure bearing information and surface fragility information is constructed, internal structure weakness and external decoration damage are avoided, and high-quality lossless operation is achieved; the instability risk is quantified by calculating the slip index in real time, and stabilizing measures such as grabbing posture fine adjustment and the like are automatically executed according to the risk level, so that overturning and collapse of the stack caused by accumulative errors or external disturbance can be effectively prevented; the maximum allowable stacking layer number is dynamically calculated by analyzing the stress relaxation gradient of the skeleton and the spatial distribution of supporting points in real time, so that the storage space utilization rate is maximized on the premise of ensuring safety; a dual instability judgment mechanism based on pressure dispersion and interlayer displacement acceleration is set, and dynamic optimization and ultimate safety guarantee of the stacking process are achieved.

The application discloses a high-temperature-resistant beryllium copper alloy for microswitches and a preparation method thereof, and belongs to the technical field of electronic component manufacturing. The alloy composition is as follows in terms of percentage by weight: Be 0.20%-0.50%, Co 1.20%-1.30%, Ni 3.20%-3.50%, W 0.30%-0.50%, Fe 0.12%-0.15%, Zr 0.16%-0.20%, Y 0.12%-0.15%, B 0.010%-0.015%, Pb≤0.003%, Sn≤0.003%, total impurities≤0.01%, and the balance being Cu. The preparation method comprises the following steps: 1280-1300 DEG C. smelting, 1620-1650 DEG C. high-temperature refining, homogenization treatment, hot rolling, annealing, solid solution, twice cold rolling and intermediate annealing, two-stage aging treatment, and finally, a strip with a thickness of 0.5-2.0 mm and an average grain size of 5-7 um is obtained. The obtained product has a yield strength of ≥980 MPa, a tensile strength of ≥1200 MPa, an elongation of ≥5%, and an elastic modulus of ≥115 GPa, and has excellent high-temperature strength, elastic stability and stress relaxation resistance.

The invention relates to the technical field of resin-based composite material structural member forming, in particular to a preparation process of a high-performance carbon fiber cantilever beam free of micromolecule release under vacuum, which comprises the following steps: step 1, tool preparation: 1.1, scrubbing the working surface of a mold with acetone or alcohol to ensure that the surface of the mold is clean and free of grease; 1.2, checking whether the die has defects or not and checking whether scribing is accurate or not; 1.3, a mold release agent is brushed on the molding surface of the mold, and when the mold release agent is brushed, the surface temperature of the mold should be 15 DEG C or above; the problem of creep deformation of a traditional metal cantilever beam is solved, and the traditional metal cantilever beam (such as aluminum alloy and steel) is prone to creep deformation after long-term use or in a high-temperature environment, so that deformation, stress relaxation and even breakage are caused. The cantilever beam is prepared from the carbon fiber composite material, the problems are effectively solved, and the cantilever beam has excellent creep resistance, can still keep stable structure after being used for a long time at normal temperature, and is suitable for high-precision and long-service-life application scenes.

A method includes: providing a passivation layer with an embedded MIM capacitor; forming a redistribution layer (RDL) above the passivation layer; and forming an opening in the RDL above the MIM capacitor, wherein the opening separates the RDL into first and second RDL structures, wherein each of the first and second RDL structures has a convex-shaped profile on a sidewall that defines the opening that separates the first RDL structure from the second RDL structure, and wherein the convex-shaped profile on the sidewalls resists stress migration from the RDL to the MIM capacitor to resist stress migration induced cracks forming in the MIM capacitor. The forming an opening includes: removing a portion of the RDL to a first depth using first etching operations; and removing a portion of the RDL to a second depth by laterally etching sidewalls of the first and second RDL structures.

The invention discloses a metal wire stress relieving process, and belongs to the technical field of metal material heat treatment. The metal wire is sequentially subjected to heating, spheroidizing annealing treatment and slow cooling; in the slow cooling process, the metal wire is kept at a constant temperature in a first preset temperature interval so as to eliminate internal residual stress of the metal wire; namely, spheroidizing annealing and stress relief are integrated in a continuous process, a stress relaxation platform is arranged in a specific cooling stage after wire rod spheroidizing, stress release is achieved through the creep effect of a material in the temperature interval, and independent stress relief treatment does not need to be conducted after spheroidizing annealing. The continuous production line is started to synchronously complete tissue softening and stress relief, so that the treated wire can simultaneously meet the requirements of low hardness and low residual stress, the problems of subsequent drawing cracking, unstable size and the like caused by the residual stress are avoided, and the heat treatment efficiency and the wire processing qualification rate are improved.

This invention discloses a Cu-Ni-Si alloy material and its preparation method, belonging to the field of non-ferrous metal processing technology. The preparation method includes: melting and melt protection, horizontal continuous casting, solution treatment, cold rolling, first-stage aging, intermediate cold working, second-stage aging, and low-temperature tension annealing. By using a copper-silicon alloy as the silicon source and combining a melt protection strategy with protective gas and covering agents, this invention effectively solves the problem of crystallizer blockage caused by Si oxidation and slagging during horizontal continuous casting. Simultaneously, by rapidly cooling the horizontal continuous casting to obtain a supersaturated fine-grained billet, combined with direct large-deformation cold rolling without intermediate annealing, and a synergistic heat treatment process of "pre-aging – intermediate cold working – final aging – low-temperature tension annealing," an excellent match is achieved between high strength (>800MPa), high electrical conductivity (>45% IACS), and low stress relaxation rate (<10%). This invention features a short process, low energy consumption, and high yield, making it suitable for the industrial production of high-performance copper alloy strips.

The invention discloses a double-process multi-pass controlled oxidation machining method and die for a difficult-to-deform alloy plate, and belongs to the technical field of metal material hot working, and the method comprises the steps of original process parameter configuration, plate blank blanking, grinding and polishing, multi-pass machining and forming, workpiece procedure flow direction decision making and part finishing and finished product detection. The multi-pass processing forming comprises oxygen control pre-forming and vacuum thermal shaping which are alternately executed, and the oxygen control pre-forming comprises the steps that in the interval from the room temperature to the service temperature, a uniform forming device is adopted for pre-forming a plate to be in the target shape of the current pass; the vacuum thermal shaping comprises the following steps: placing the preformed part in a shaping mold, closing the mold, vacuumizing, performing high-temperature stress relaxation shaping in a stress relaxation temperature interval, and eliminating springback. According to the method, through alternate execution of oxygen-controlled preforming and vacuum thermal correction, real-time data feedback correction and establishment of a forming feedback channel, the material oxidation degree is effectively reduced, the forming precision and stability are improved, the plate utilization rate is optimized, and the part service performance and surface quality are improved.

The invention discloses a control method for layering defects of medium-wide strip steel for a chain wheel. The control method specifically comprises the following steps: 1) smelting low-sulfur control; (2) controlling the superheat degree of molten steel and equipment precision in the continuous casting process; (3) the continuous casting secondary cooling process is improved, the specific water flow is increased, and internal cracks caused by uneven cooling are avoided; and (4) a casting blank warm charging process: firstly carrying out stack cooling and slow cooling on the continuously cast casting blank for more than 24 hours, and charging after the casting blank is cooled to 100-300 DEG C, so as to finish initial diffusion and escape of hydrogen and stress relaxation of the casting blank. And 5) rough rolling and large rolling reduction: ensuring enough compression ratio in order to ensure that the internal structure of the casting blank is welded in the rolling process. Through multi-dimensional cooperative control of smelting purification, continuous casting homogenization and rolling densification, the internal quality of the steel is remarkably improved.

The invention belongs to the technical field of supporting, and discloses an excavation auxiliary device suitable for an underground space structure of a soft rock stratum, which is characterized by comprising a positioning mechanism, the middle part of the positioning mechanism is rotatably connected with a first supporting mechanism, and the top of the positioning mechanism is also provided with a positioning frame; and the middle part of the positioning frame is rotationally connected with a second supporting mechanism. According to the large-span extra-large-section underground space structure of the soft rock stratum, the whole section is divided into seven pilot tunnels to be excavated in a segmented mode, primary support is immediately constructed after excavation in the segmented pilot tunnels, the phenomenon that the vault settlement value is increased due to overlarge span and tunnel face stress relaxation is eliminated, the stability of the excavation face is enhanced, and the vault settlement value and the ground settlement value are effectively controlled; and when a pilot tunnel a and a pilot tunnel b are excavated, the two sets of devices are placed on the two side walls of the pilot tunnel in a staggered mode, the positioning mechanism 1 is fixed through anchor rods, preliminary supporting of the pilot tunnel a and the pilot tunnel b is achieved, and supporting is more convenient.