372 results about "Thermal expansion" patented technology

The invention provides a disc laser cutting, chamfering and splitting method, and relates to the technical field of glass product processing, and the method comprises the following steps: carrying out annular shape cutting on a to-be-processed glass raw material by using Bessel laser, and determining a mark point at the center of the to-be-processed glass raw material; according to the marking points, a camera is used for marking and positioning, and coordinate values of chamfering are obtained; performing laser chamfering on the current glass raw material according to the chamfering coordinate value to obtain a chamfered workpiece; the chamfered workpiece is sequentially moved below an outer ring heating block and an inner ring heating block, outer ring waste materials and inner ring waste materials sequentially and automatically fall off through the thermal expansion and cold contraction effect, and the finished annular glass piece is obtained. The problems of high glass processing cost, poor precision and environmental pollution in the prior art are solved.

The invention relates to the field of textile detection, and discloses a fabric flame retardance analysis method based on infrared thermal imaging sensing data, which comprises the following steps: performing non-contact temperature measurement on a fabric sample in a controlled heat shock disturbance field, acquiring an infrared imaging signal sequence, and performing energy projection rearrangement on the infrared imaging signal sequence; based on the discontinuous change of the energy flow density in the primary thermal behavior field, establishing a boundary disturbance model of a local overheating region, and comparing the morphological difference between a thermal expansion path and a radiation energy attenuation region; mapping the heat potential difference of each region in the critical response diagram into an energy constraint state inside the material, and deducing time bias distribution of energy conduction; introducing a spectrum equalization function under time offset distribution, and executing asymmetric compensation on local abnormal points of the infrared response data; and based on the decomposition threshold dynamic trajectory, calculating a flame-retardant response equilibrium rate and an energy flow retention rate, and forming a flame-retardant performance evaluation index. The method has the advantage of improving the accuracy of flame retardant detection.

The invention discloses a test device for measuring the compression strength of a composite material plate, which comprises an upper box body and a lower box body, a guide column is arranged between the upper box body and the lower box body, an upper clamping assembly is arranged at the lower end of the upper box body, a lower clamping assembly is arranged at the upper end of the lower box body, and the upper clamping assembly and the lower clamping assembly have the same structure and opposite installation directions. The upper clamping assembly or the lower clamping assembly comprises two wedge-shaped clamping block units which are oppositely arranged, and the end part of the test piece is clamped between the two wedge-shaped clamping block units. The invention also discloses a test method for measuring the compression strength of the composite material plate. The test device can stably work for a long time in high and low temperature environments, meets the test requirements of a compression test, adopts a split design, is rapid in clamping, can effectively resist bending and torsional deformation, improves the test efficiency and accuracy, keeps reliable clamping all the time in the test process, and is simple in structure and convenient to operate. And the problem of clamping failure caused by thermal expansion and cold contraction is effectively solved.

The invention provides a preparation method and application of ceramic slurry for high-temperature bonding of aluminum nitride ceramics, and relates to the technical field of high-temperature ceramic materials.The preparation method comprises the following steps that firstly, an organic carrier is prepared, a polymer binder, an organic solvent, a plasticizer and a dispersing agent are weighed according to the weight ratio and stirred at the temperature of 60-70 DEG C till complete dissolution and clarification are achieved for use; 2, an inorganic functional phase is prepared, aluminum nitride powder, yttrium oxide powder and alkaline earth metal oxide powder are weighed according to the weight proportion and placed in a ball milling tank to be evenly mixed, the obtained ceramic slurry serves as a bonding layer, the tolerable temperature can reach 1000 DEG C or above and is far higher than that of metal brazing filler metal, and the ceramic slurry is suitable for severe environments such as aerospace and high-temperature sensors. The main components of the bonding layer are consistent with the base material, and the thermal expansion coefficient is highly matched, so that the thermal stress can be greatly relieved, and the failure of the device caused by thermal fatigue in the temperature cycle is avoided.

The invention discloses a manufacturing method for preventing a pole piece from cracking and the pole piece, and the method comprises the following steps: preparing double-layer composite slurry with matched thermal expansion coefficient gradient, coating the double-layer composite slurry on the surface of a copper foil, and coating surface slurry on bottom slurry; the coated pole piece sequentially passes through a copper foil side infrared radiation heating area, a coating surface cold and hot air alternate drying area and an alternating magnetic field treatment area, bottom layer slurry is preferentially shrunk through infrared radiation, surface layer solvent gradient volatilization is controlled through cold and hot air alternation, and a magnetic field induces graphene to be directionally arranged so as to fill microcracks; performing pulse laser scanning on the dried pole piece, and softening a surface adhesive to realize in-situ self-repairing; coating strain distribution is monitored in real time, and drying parameters are dynamically adjusted. Compared with the prior art, the manufacturing method can effectively prevent cracks from appearing on the surface of the pole piece.

The invention discloses a heat distribution pipeline heat preservation and energy saving device, and relates to the technical field of pipeline heat preservation, in particular to a heat distribution pipeline heat preservation and energy saving device which comprises a heat distribution pipeline and an outer pipe wrapping the heat distribution pipeline, and a rubber pipe capable of deforming is arranged between the heat distribution pipeline and the outer pipe. Through the thermal expansion and cold contraction characteristics of inert gas filled in the extrusion cavity and the arrangement that the first heat preservation cabin is communicated through the first communication opening, when the external environment temperature distribution is uneven, the inert gas in the extrusion cavity of the perpendicular incidence face expands to push the rubber pipe to deform; carbon dioxide in a first heat preservation cabin in a compressed area is transferred to the shady side through a first communication opening, a heat preservation gas layer on the shady side is promoted to expand and thicken, and meanwhile a main movable plate is driven to rotate around a limiting column so that the whole heat preservation structure can deviate. The purposes of dynamically adjusting the thickness of the heat-preservation air layer according to the environment temperature difference, strengthening the heat-preservation effect of the shady face and reducing heat loss are achieved.

The invention provides a doped yttrium hydride neutron moderation material and a preparation method and application thereof, and belongs to the technical field of radiation shielding materials. At least one of samarium, europium and gadolinium is doped in yttrium hydride in the form of hydride, and the mass ratio of metal yttrium to metal gadolinium to metal europium to metal samarium is controlled, so that the neutron moderation effect of the neutron moderation material can be improved. According to the invention, at least one of gadolinium hydride, europium hydride and samarium hydride is mixed with yttrium hydride under the protective atmosphere, so that the mass content of each element in the doped yttrium hydride neutron moderation material can be accurately controlled. According to the invention, the mixture is sintered and molded, and the sintering parameters of sintering and molding are controlled, so that the components of the mixture are sintered in a compact state, cracks generated by thermal expansion and cold contraction can be reduced, and the doped yttrium hydride keeps high density and has fewer cracks and defects.

The invention belongs to the technical field of sliding component casting, and particularly relates to a cast iron sliding component and a preparation method thereof.The cast iron sliding component is made of silicon solid solution ferrite nodular cast iron, the structure of the material is uniform and single ferrite, and the cast iron sliding component comprises, by mass, 2.90%-3.20% of C, 3.9%-4.35% of Si, smaller than or equal to 0.4% and not larger than 0 of Mn, smaller than or equal to 0.04% and not larger than 0 of P, smaller than or equal to 0.02% and not larger than 0 of S and the balance Fe and inevitable impurities. The alloy comprises the following components in percentage by weight: less than or equal to 0.020% of S but not 0, 0.040-0.060% of Mg, 0.005-0.009% of Sb and the balance of iron and inevitable trace elements. The sliding component has a full-ferrite matrix structure and is good in structure uniformity, machining residual stress is reduced, meanwhile, the thermal expansion coefficient is reduced, nitriding deformation is avoided, annealing heat treatment is not needed after casting knockout and before honing, secondary honing after nitriding is omitted, and the non-uniformity of the final nitriding structure is reduced.

The invention discloses a high-temperature-resistant epoxy resin-based mold prepreg as well as a preparation method and application thereof, and belongs to the technical field of resin-based composite materials. The preparation method comprises the following steps: mixing and stirring the epoxy resin A and the heat-conducting filler, and grinding to obtain a premix I; mixing and stirring a curing agent and epoxy resin B to obtain a premix II; mixing and stirring the premix I and the premix II to obtain a mixture; and coating release paper with the mixture, covering the release paper with fiber cloth, and carrying out hot-pressing impregnation to obtain the high-temperature-resistant epoxy resin-based mold prepreg. The invention also discloses the high-temperature-resistant epoxy resin-based mold prepreg prepared by the method and application of the high-temperature-resistant epoxy resin-based mold prepreg in preparation of a composite material mold. The prepreg prepared by the method has excellent high temperature resistance, low thermal expansion coefficient and high heat conductivity coefficient, and the service life of a composite material mold can be greatly prolonged.

The invention discloses an in-situ device and method for measuring curvature change of a sample in an ion irradiation process, and the in-situ device comprises a sample clamping and beam measurement assembly which is used for positioning the sample in the irradiation direction of an ion beam, can achieve the safe clamping of the sample and the free generation of curvature change at the same time, and is used for measuring the curvature change of the sample. The measurement of irradiation fluence, temperature and curvature can be realized at the same time; the temperature measurement and control assembly can measure and control the temperature of the sample; the in-situ profile measurement assembly can realize in-situ surface curvature measurement of the sample in the irradiation and heating processes; the vacuum component is used for providing a vacuum environment for the components; and the in-situ device is arranged at the terminal of the ion accelerator to measure the curvature change of the sample in the ion irradiation process. The method can be used for researching material size change, modulus, thermal expansion rate change and the like caused by factors such as defects, crystal growth and helium bubbles in the irradiation process of materials, and provides means for research, development, screening and evaluation of nuclear materials.

The invention provides a polyurethane composite material as well as a preparation method and application thereof, and relates to the field of polyurethane materials. The polyurethane composite material comprises the following components or is formed by the following raw materials in parts by weight: 100 parts of a polyurethane prepolymer; 10 to 40 parts of modified whisker; 5 to 20 parts of modified nanofiber; the modified crystal whiskers are crystal whiskers modified by a first isocyanate modifier and a first free radical modifier, and the chain extender is modified by a second isocyanate modifier and a second free radical modifier; the modified nanofiber is a nanofiber modified by a first diisocyanate type modifier and a second free radical type modifier. According to the polyurethane composite material provided by the invention, grafted and modified whiskers and nanofibers are introduced and directly react with polyurethane to form a molecular-level interpenetrating network, so that the linear thermal expansion coefficient of the polyurethane material is remarkably reduced, and meanwhile, the mechanical property of the polyurethane material is improved.

The invention relates to the technical field of heat treatment, and discloses a heat treatment process and heat treatment equipment for a nanocrystalline magnetic core, the heat treatment equipment comprises a bottom plate I, the top of the bottom plate I is fixedly connected with a base, the heat treatment equipment further comprises a heating mechanism, the heating mechanism comprises a heating frame fixedly connected to the inner wall of the base, and the outer wall of the heating frame is fixedly connected with a cooling fan; by arranging the heating mechanism, the device abandons traditional bolt fastening and other fixing modes, the placing assembly can be rapidly fixed or disassembled only by lifting a connector at the top, the operation process is simple and efficient, the time for replacing and installing a magnetic core of equipment is greatly shortened, and the replacement efficiency of the magnetic core of the equipment is improved. Meanwhile, by means of the physical characteristic that materials expand with heat and contract with cold, the fastening effect between the containing assembly and the equipment body can be enhanced in the heating state, it is guaranteed that the magnetic core does not displace or shake in the hot working process, and the hot working effect of the equipment is improved.

The invention relates to the technical field of thermal barrier coatings, in particular to a gadolinium oxide and aluminum oxide co-doped modified YSZ: Dy thermal barrier sensing coating material as well as a preparation method and application thereof. The invention provides a thermal barrier sensing coating material. The chemical composition of the thermal barrier sensing coating material is Y Gd Al < c > Zr < d > DeyOf, wherein a is equal to 0.01 to 0.04, b is equal to 0.15 to 0.35, c is equal to 0.40 to 0.60, d is equal to 0.35 to 0.70, e is equal to 0.01 to 0.02, and f is equal to 1.50 to 1.70. The temperature measurement upper limit of the thermal barrier sensing coating material is 1200 DEG C, and the average thermal expansion coefficient is increased by 18% at the room temperature of 1200 DEG C, so that the thermal shock resistance of the thermal barrier sensing coating is effectively improved, and the service life of the thermal barrier sensing coating is prolonged.

Provided is a glass which can replace a Li2O-Al2O3-SiO2-based crystallized glass and which has a low coefficient of linear thermal expansion and excellent light transmittance. A glass characterized by containing, in mass%, 45 to 80% of SiO2, 10 to 30% of Al2O3, 0 to 12% of B2O3, and 0 to 5% of Li2O.

A method of integrating a first substrate having a first surface with a first insulating material and a first contact structure with a second substrate having a second surface with a second insulating material and a second contact structure. The first insulating material is directly bonded to the second insulating material. A portion of the first substrate is removed to leave a remaining portion. A third substrate having a coefficient of thermal expansion (CTE) substantially the same as a CTE of the first substrate is bonded to the remaining portion. The bonded substrates are heated to facilitate electrical contact between the first and second contact structures. The third substrate is removed after heating to provide a bonded structure with reliable electrical contacts.

The present invention provides a susceptor comprising: a base member; and a dielectric plate adhered to the base member by means of an adhesive layer, wherein the base member is a metal-ceramic composite, and a thermal expansion coefficient ratio of the metal-ceramic composite to a ceramic material of the dielectric plate is less than 1.5 in the entire temperature range of -100℃ to 200℃.

Provided is an alloy having a high strength and a low thermal expansion coefficient. The alloy according to the present disclosure includes a chemical composition containing, in mass %: C: 0.10% or less, Si: 0.50% or less, Mn: 0.15 to 0.60%, P: 0.015% or less, 5: 0.0030% or less, Ni: 30.0 to 40.0%, Cr: 0.50% or less, Mo: 0.50% or less, Co: 0.250% or less, Al: 0.0150% or less, Ca: 0.0050% or less, Mg: 0.0300% or less, N: 0.0100% or less, O: 0.0300% or less, Pb: 0.0040% or less, and Zn: 0.020% or less, one or more elements selected from the group consisting of Nb: 0 to less than 0.145%, Ti: 0 to less than 0.145%, and. V: 0 to less than 0.145%: 0.015 to less than 0.145% in total, with the balance being Fe and impurities, and satisfying Formula (1).(Nb+3×Ti+V) / (C+N)≤6.00  (1)

The utility model relates to the technical field of PEEK shaft sleeves, and discloses a PEEK shaft sleeve for isolating shaft current, which comprises a shaft, the right side of the outer surface of the shaft is sleeved with a PEEK shaft sleeve, and the right side of the outer surface of the PEEK shaft sleeve is provided with a glue groove. According to the PEEK shaft sleeve for isolating the shaft current, through the arrangement of only one group of PEEK shaft sleeves, the PEEK shaft sleeve is convenient to install, does not have any influence on other parts, is a simple and feasible scheme, can effectively isolate the shaft current and prevent electrocorrosion of a bearing, is low in cost and does not need regular maintenance, meanwhile, the PEEK shaft sleeve is made of a PEEK material, and the PEEK material has relatively high mechanical performance, so that the shaft current can be isolated effectively. Compared with other plastic materials, the composite material has the advantages of higher mechanical rigidity, high temperature resistance, corrosion resistance, thermal expansion coefficient close to that of metal and small humidity influence, so that the composite material can provide a stable size in a wide-temperature and high-humidity environment, can ensure a stable matching relationship between the composite material and a bearing and a shaft, and ensures the system stability.

The invention relates to the technical field of functional material preparation, in particular to a high-low-temperature-resistant high-performance packaging composite material for a vehicle energy storage system and a forming process of the high-low-temperature-resistant high-performance packaging composite material. 30-50 parts of a heat-conducting filler; 5-10 parts of a high and low temperature resistant modifier; 3-8 parts of a toughening agent; 0.5-2 parts of a catalyst; 1-3 parts of an auxiliary agent; a three-dimensional heat conduction network is formed in the composite material, the heat conduction coefficient is larger than or equal to 3.5 W / (mK), the low-temperature tensile strength at-40 DEG C is larger than or equal to 15 MPa, the high-temperature tensile strength at 150 DEG C is larger than or equal to 12 MPa, the volume resistivity is larger than or equal to 1 * 10 < 14 > omegacm, and the thermal expansion coefficient is smaller than or The material is excellent in thermal conductivity, balanced in high and low temperature resistance and mechanical property, good in aging resistance and barrier property, optimized in forming process and high in performance consistency, and provides reliable guarantee for safe and stable operation of a vehicle energy storage system.

This invention belongs to the field of glass technology and relates to a high-temperature resistant structural glass material, its preparation method, and its applications. The glass is composed of the following components by mass percentage: 60%-70% silicon dioxide, 5.5%-11% boric acid, 0.1%-5% aluminum hydroxide, 0%-3% potassium nitrate, 5.5%-13% potassium carbonate, 0%-12% sodium carbonate, 0.1%-4% calcium carbonate, 0%-2% calcium fluoride, 0%-1% lithium carbonate, 0%-2% basic magnesium carbonate, 0.1%-1% titanium dioxide, 0%-2% zirconium dioxide, and 0%-1% cerium dioxide; the total mass percentage of potassium nitrate, potassium carbonate, sodium carbonate, and lithium carbonate does not exceed 22%. This structural glass possesses a high softening temperature, a suitable coefficient of thermal expansion, high-temperature resistance, thermal shock resistance, and processing performance, making it suitable as a structural material for optoelectronic devices.

The present invention discloses a low-expansion glass-ceramic, a preparation method, and applications thereof. The low-expansion glass-ceramic comprises the following components by weight: 56-67% SiO2, 18-27% Al2O3, 3.1-7.0% Li2O, 0.1-0.5% MgO, 0.1-0.9% ZnO, 1.0-2.9% P2O5, 1.0-2.9% TiO2, 1.0-2.9% ZrO2, 0.5-4% Gd2O3, 0.6-1.5% SnO2, and 0.1-0.4% CaF2. The low-expansion glass-ceramic prepared by the present invention has excellent properties such as a low thermal expansion coefficient and good visible light transmittance. The low-expansion glass-ceramic prepared by this method can be used in the field of extreme ultraviolet lithography.

Provided is a glass substrate that reduces errors in the correction of thermal deformation.　This glass substrate has a rectangular main surface (MS1). When the main surface is divided into nine equal parts in a direction perpendicular to a first side (S1) and divided into nine equal parts in a direction perpendicular to a second side (S2), thereby dividing the main surface into a group of 81 rectangular regions (A11-A99), the rectangular regions, in the group of 81 rectangular regions, the centers of which are located on a diagonal line of the main surface passing through a first vertex (P1) that is an intersection point of the first side and the second side, satisfy expression (1A), where TZ11、TZ22、TZ33、TZ44、TZ55、TZ66、TZ77、TZ88、and TZ99 are zero crossover temperatures in ˚C, at which the thermal expansion coefficient of the glass substrate becomes 0 ppb / K, starting from the closest to the first vertex. (1A): (TZ11+TZ99)-(TZ22+TZ88)＜0.00

The invention discloses a method and device for measuring the expansion coefficient of an epoxy material, and the method comprises the steps: obtaining an epoxy material sample, gradually increasing the temperature value in an expansion cavity, and measuring the size of the epoxy material sample at the temperature value through a laser system, a signal receiving system and a data processing system, and generating a size-temperature change curve based on the size of the epoxy material sample at each temperature value, and calculating the expansion coefficient of the epoxy material sample at each temperature section according to the size-temperature change curve. Therefore, when the epoxy material is measured in the expansion cavity, the method can be suitable for a large-size sample, the epoxy material is heated in the expansion cavity and is not limited by high temperature, so that the measurement of the expansion coefficient of the epoxy material has a wider temperature range, and the expansion coefficient of the epoxy material can be measured by constructing a curve of the size of the epoxy material changing along with the temperature. The expansion coefficient of the epoxy material is represented more comprehensively and accurately, so that the applicability of the epoxy material in various temperature scenes is determined more accurately.

The invention relates to the technical field of dissimilar metal-based composite materials for module packaging, and discloses a copper-molybdenum-copper-copper composite material with a step structure and a preparation method of the copper-molybdenum-copper-copper composite material. In order to solve the product failure problems of buckling deformation, large size fluctuation and the like existing in an existing complex molybdenum-copper-copper structural part preparation method, copper with high flexibility and high heat conductivity is adopted as a bending part, and a copper-molybdenum-copper composite material with a direct welding flux at the bottom and a low thermal expansion coefficient is combined to serve as a novel structure; cladding combination of dissimilar interface materials is achieved through a laser welding method, internal stress is released through a pulse laser shock method on a weld joint, and the bending strength and reliability of a welded material structure are improved. The precise copper-molybdenum-copper / copper strip with the step structure can be efficiently and continuously prepared on a large scale, the reliability is high, the process is simple, the yield is high, and the method is worthy of production and popularization.

A glass includes silica, alumina, boria, and yttria. The glass may have high fracture toughness, often greater than 1 MPa·m1 / 2, as well as high Vickers hardness, on the order of 800 kgf / mm2 or greater. Furthermore, Applicants find that, due to surprisingly large high-temperature coefficient of thermal expansion (e.g., over 35 ppm / °C at about 875°C) and high elastic modulus (e.g., >120 GPa) the glass may be particularly suitable for thermal tempering, which may strengthen a corresponding article comprising the glass.

The utility model discloses a zipper machine for conveying high-temperature materials, and relates to the technical field of material conveying equipment, the zipper machine comprises a conveying groove body and a driving unit, a transmission shaft is rotatably arranged in the conveying groove body, the driving unit is used for driving the transmission shaft to rotate, and extension shafts are coaxially and fixedly arranged at the two ends of the transmission shaft; the two sides of the conveying groove body communicate with supporting sleeves, the extending shafts on the corresponding sides are sleeved with the supporting sleeves, the ends, away from the conveying groove body, of the supporting sleeves communicate with sealing covers, the distance between the sealing covers and the conveying groove body is not smaller than 300 mm, and oil seals are arranged in the sealing covers and used for sealing gaps between the extending shafts and the supporting sleeves. The extension shaft is sleeved with a bearing, and the outer ring of the bearing is fixedly connected with the sealing cover. The influence of heat transferred by high-temperature materials on the bearing and the oil seal can be effectively reduced, the problem that lubricating oil needs to be frequently filled due to high-temperature evaporation is solved, and meanwhile structural thermal deformation and damage caused by thermal expansion are prevented.

The application discloses a flue gas heat exchanger pipe connecting structure capable of preventing heat stress from causing leakage. The structure comprises a heat exchange pipe, which is connected with a flue wall in a soft manner to eliminate the influence of heat stress between the heat exchange pipe and the flue wall. An expansion joint is arranged on the heat exchange pipe in the flue to provide a buffer space for the deformation of the heat exchange pipe caused by thermal expansion and contraction in the axial direction. The heat exchange pipe and the flue wall are connected in a soft manner by using a fixing nut, an elastic gasket and a fixing ring, and the gasket is made of polytetrafluoroethylene material. The axial and radial deformation of the heat exchange pipe caused by thermal expansion and contraction is effectively absorbed while the sealing is considered, so as to offset the influence of heat stress between the heat exchange pipe and the flue wall. The heat exchange pipe and the expansion joint are welded in the flue, and the expansion joint provides a buffer space for the deformation of the heat exchange pipe body caused by thermal expansion and contraction in the axial direction, so that the influence of heat stress on the connecting point of the flue gas heat exchanger and the flue wall can be further inhibited.

The utility model relates to the technical field of water-based building emulsion production, in particular to a raw material storage device for water-based building emulsion production, which comprises a storage tank, the top of the storage tank is connected with a top cover, a pressure adjusting mechanism is mounted on the top cover, and the pressure adjusting mechanism comprises a fixing ring fixedly mounted on the top cover. A conical telescopic cover is connected to the bottom of the fixing ring, a pressure sensor is fixedly installed on the inner top of the fixing ring and electrically connected with the alarm device, and a telescopic force application piece matched with the pressure sensor is arranged at the inner bottom of the conical telescopic cover. According to the utility model, automatic expansion and contraction adjustment is facilitated, the problem of raw material deterioration caused by fracture due to hot dirty and cold contraction is solved, meanwhile, the storage space is ensured not to change, and the storage in a temperature difference region is facilitated.

The invention relates to the technical field of anti-seepage membrane construction, in particular to a multi-layer composite long-acting durable anti-seepage construction process which comprises the following steps: preparation before construction: providing a laying and welding plane layout diagram, checking the quality of a construction site and an anti-seepage membrane, and ensuring that construction equipment and materials are qualified; the anti-seepage film is cut, transported and loaded according to the design requirement, the film is smoothly and firmly attached during laying, the length of expansion caused by heat and contraction caused by cold is reserved, and materials are prevented from being damaged; a double-welding-seam overlap welding process is adopted, the surface is cleaned before welding, a welding machine gun head is kept vertical, the change of the overlap width is paid attention to, and an air pressure leak detection test is conducted after welding; anchoring an impermeable membrane: excavating and flattening an anchoring groove, wherein the compaction degree of backfill soil is not less than 95%; according to temporary measures in the construction process, ballast measures are adopted to prevent the impermeable film from being blown up by wind, construction records are made, and by optimizing the construction process of the HDPE impermeable film and improving the welding technology and the anchoring technology, the construction quality of the impermeable film is effectively improved, and the construction cost is reduced.

The invention provides a method for solving crazing defects of a composite material product, which comprises the following steps: a) controlling the temperature of liquid resin to be within a preset range in the process of applying the liquid resin to the inside and the surface of a solid material component of the composite material product; b) in the pre-curing process of the composite material, controlling the actual heating rate of the liquid composite material to be within a preset range; and c) in the post-curing / heat treatment process of the composite material, controlling the actual temperature of the composite material to be within a preset range. By controlling the infiltration, permeation and adsorption process of the liquid-state base material, the liquid-state base material reaches the optimized infiltration and adsorption state on the molecular level on each interface of different materials and different combined structures; and meanwhile, local stress concentration caused by the difference of thermal expansion and cold contraction multi-mode response of the material is controlled to be lower than a critical value for inducing craze formation, so that the craze whitening phenomenon of a composite material product is solved.