450 results about "Linear expansion coefficient" patented technology

The present invention discloses a hot-end sealing device for an air preheater that compensates for the expansion difference between a sealing sheet and a backing plate, which at least includes a sealing sheet and a backing plate. The sealing sheet is provided with sealing sheet mounting holes distributed along the length direction, and the backing plate is provided with backing plate mounting holes distributed along the length direction. The linear expansion coefficient of the sealing sheet is different from that of the backing plate. The sealing sheet and the backing plate are relatively fixed by clamping bolts that simultaneously pass through the sealing sheet mounting holes and the backing plate mounting holes. One end close to the rotor central cylinder is the expansion starting end, and the clamping bolts at the expansion starting end are fully tightened and fixed, while the remaining clamping bolts are not fully tightened and fixed, so that the sealing sheet and the backing plate freely expand towards the other end close to the rotor outer edge angle steel after being heated. At least one set of two-dimensional guiding mechanisms is arranged between the sealing sheet and the backing plate downstream of the expansion starting end. The above device maximally compensates for the triangular air leakage area at the hot end of the air preheater, significantly reduces the air leakage rate of the air preheater, has good stability and a long service life.

The invention relates to the technical field of auxiliary power, in particular to an air supply device of an auxiliary power system. The device comprises an air inlet duct shell, an air inlet air pocket, an air inlet duct outer ring, an air inlet volute, a labyrinth ring, a locking unit and a rotor. The axial end face of the air inlet air pocket is coaxially connected with the air inlet channel shell in an abutting mode. The air inlet channel outer ring comprises an outer sealing cylinder and an outer extending ring which are coaxially and fixedly connected, and the axial end face of the outer extending ring is coaxially connected with the air inlet air pocket in an abutting mode. The air inlet volute comprises a volute positioning cylinder and a spiral air channel shell which are fixedly connected, and the end face of the air inlet volute coaxially abuts against the outer extending ring. The labyrinth ring is clamped between the air inlet channel outer ring and the air inlet volute, the inner peripheral wall and the outer peripheral wall are attached to the first sealing face and the second sealing face respectively, the radial linear expansion coefficient of the labyrinth ring is larger than that of the first sealing face and that of the second sealing face, the labyrinth ring comprises a ring body and a plurality of pressure reduction gear rings axially arranged at intervals, and a stepped pressure relief cavity is formed between every two adjacent pressure reduction gear rings. In this way, the problem that gas leakage is prone to occurring at the connecting position of the air inlet end shell of the auxiliary power system is solved.

The invention relates to a sample preparation method for coating thickness detection, which comprises the following steps: circularly heating and cooling a base material to obtain a weakly combined base material with a base material body and a coating locally separated; and forming a cut extending along the thickness direction of the coating in a local separation area of the coating of the weak combination base material to obtain a coating section sample vertical to the surface of the base material. Due to the difference of linear cutting expansion coefficients of a base material body and a coating, alternating thermal stress is initiated at the interface of the base material body and the coating through cyclic heating and cooling processes, so that the base material and the coating are controllably and locally separated, a weakly combined base material is obtained, and a cut extending in the thickness direction is prepared in the surface of the locally separated coating. A coating section sample perpendicular to the surface of the base material can be obtained through simple mechanical separation. The method can be used for efficiently preparing a coating sample with clear section and good integrity at low cost on the premise of not depending on expensive or high-damage equipment.

The invention relates to the technical field of sealing rings, and discloses a wide-temperature-zone sealing ring which comprises a sealing ring body, the sealing ring body comprises a sealing layer, a thin film layer and a compensation layer, the outer portion of the thin film layer is arranged in the sealing layer, and the outer portion of the compensation layer is arranged in the thin film layer; the sealing layer and the thin film layer are supported by different materials and are made of fully-sealed elastic flexible materials, and the thickness of the thin film layer is smaller than that of the sealing layer; the compensation layer and the sealing layer are supported by different materials, and the linear expansion of the materials of the compensation layer and the sealing layer is opposite; the thickness of the compensation layer is inversely proportional to the thickness of the sealing layer according to the linear expansion coefficients of the two materials. The materials of the sealing layer and the compensation layer are selected, so that the compensation layer expands at low temperature to offset lost sealing pressure, the compensation layer shrinks at high temperature to buffer excessive extrusion, uniform contact stress of the sealing ring is maintained in extreme temperature fluctuation, and the effect of zero-damage self-adaptive sealing in the whole temperature range is achieved.

The invention discloses liquid tank assembly welding equipment and a welding thermal compensation method, and relates to the technical field of liquid tank assembly welding, and the specific method comprises the following steps: obtaining a real-time linear expansion coefficient introducing temperature nonlinearity, calculating to obtain total welding deformation superposed by thermal expansion and phase change shrinkage through a calibrated phase change fraction and a phase change volume expansion coefficient, and obtaining the welding residual strain of the previous layer through the residual strain coefficient, correcting the actually measured welding strain in the strain data, obtaining the corrected actually measured strain of the current layer, and driving and adjusting the welding path of the next layer according to the total welding deformation when entering the welding of the next layer. The corrected actual measurement strain of the current layer is directly written into a system register and covers the actual measurement welding strain, through dynamic calibration of a linear expansion coefficient, welding gun path compensation is directly guided, actual measurement data of the current layer are corrected, and a complete chain of parameter correction, deformation calculation, path compensation and residual stress closed-loop control is formed; and finally, the effect of reducing the multi-layer welding thermal deformation error is achieved.

The invention relates to the technical field of building construction intellectualization, in particular to a building construction intelligent monitoring system based on multi-source sensor data fusion. Comprising a data acquisition and storage unit; a data fusion processing unit; the construction state analysis unit uses an improved anomaly detection algorithm; a risk assessment early warning unit; and a visualization and decision-making unit. Through the dynamic adaptation module, the structural displacement feature weight is adjusted based on the construction stage parameters to preferentially extract the construction key stage structural features, and the structural material elastic deformation limit is corrected in combination with the material linear expansion coefficient and the temperature difference value; meanwhile, the dynamic critical generation module generates a risk critical judgment basis changing along with the construction process in combination with structural bearing capacity parameters and equipment mechanical stress limits in the construction stage, so that the problem that abnormal detection and risk judgment are lack of dynamic adaptability is solved; and the accuracy of personnel border crossing, equipment abnormity and structure abnormity identification and the adaptability of risk assessment are effectively improved.

The present invention provides glass fibers that make it possible to achieve excellent long-term production stability and that, when used in a glass fiber–reinforced resin molded article, can reduce the linear expansion coefficient in the MD direction and thereby reduce anisotropy. Glass fibers according to the present invention include a plurality of glass filaments. Relative to the total mass thereof, the glass fibers include 60.0–69.0 mass% of SiO2, 18.0–26.0 mass% of Al2O3, 8.0–14.0 mass% of MgO, and 0.0–4.9 mass% of CaO, the total SiO2, Al2O3, MgO, and CaO content being at least 95.0 mass%. The glass filaments have a flat cross-sectional shape, the ratio (major axis / minor axis) of the major axis to the minor axis is 1.2–5.5, and the SiO2 content S, the Al2O3 content A, the MgO content M, the CaO content C, and the ratio (major axis / minor axis) D of the major axis to the minor axis satisfy expression (1).　(1) 228.9≤(S / A)×(C+M)2 / D1 / 4≤588.9

An anti-resonant hollow-core optical fiber (10) according to one embodiment of the present invention is provided with: an outer cladding (11) having a tubular shape; a plurality of inner cladding elements (12) each having a tubular shape and in contact with the inner wall surface of the outer cladding (11); and a cladding layer (14) that covers the outer cladding layer (11), and the space surrounded by the plurality of inner cladding layers (12) of the anti-resonant hollow-core optical fiber (10) forms a core region (11d). The average linear expansion coefficient of the outermost layer of the coating layer (14) at 20 DEG C to 30 DEG C is 10 * 10 <-5 > [ / DEG C] or less, the average linear expansion coefficient of the outermost layer of the coating layer (14) at-60 DEG C to-50 DEG C is 6 * 10 <-5 > [ / DEG C] or less, and the in-site elastic modulus of the outermost layer of the coating layer (14) is 1500 MPa or more.

An alpha-sialon phosphor which is represented by general formula (Cax, Euy) (Si12-(m + n) Alm + n) (OnN16-n), and which has an average linear expansion coefficient (alpha ') at 25-900 DEG C of 4.2-4.6 ppm / DEG C (inclusive). In the general formula, 0 < x < 2.0, 0 < y < = 0.5, 0.3 < = x + y < = 2.0, 0 < m < = 4.0, and 0 < n < = 3.0.

To provide a solid composition which achieves both a low dielectric constant and a low coefficient of linear expansion.SOLUTION: A solid composition contains a fluorine resin, and a fibrous anisotropic filler, where a reduction rate of a coefficient of linear expansion at 20°C to 200°C of the solid composition to a coefficient of linear expansion at 20°C to 200°C of the fluorine resin is 50% or more.SELECTED DRAWING: None

A semiconductor device includes a first die pad, a first semiconductor element, a sealing resin, and a reinforcement member. The first semiconductor element is bonded to the first die pad. The sealing resin covers the first semiconductor element. The reinforcement member is bonded to the first die pad. The linear expansion coefficient of the reinforcement member is smaller than the linear expansion coefficient of the sealing resin. In one example, the reinforcement member is covered with the sealing resin. The reinforcement member is located on the same side as the first semiconductor element in a first direction with respect to the first die pad.

The invention relates to a low-stress phenolic curing epoxy composition, an intermediate and a preparation method of the low-stress phenolic curing epoxy composition, by introducing a polyfunctional POSS (Polyhedral Oligomeric Silsesquioxane) structure with epoxy cyclohexyl or a polyfunctional POSS structure with epoxy cyclohexyl and phenyl, the finally obtained composition has the characteristics of low curing shrinkage, high strength, low modulus, high heat resistance and the like after being cured by utilizing the structural characteristics of the polyfunctional POSS structure; and the glass transition temperature, the bonding strength and the linear expansion coefficient are kept unchanged.

The invention belongs to the technical field of metallurgy, and particularly relates to steel for grinding balls with low cost and good wear resistance and a production method of the steel, and the steel comprises the following chemical components in percentage by weight: 0.72%-0.80% of C, 0.70%-0.80% of Mn, 0.70%-0.95% of Si, 0.70%-0.90% of Cr, less than or equal to 0.025% of S, less than or equal to 0.030% of P, 0.025%-0.040% of Alt and the balance of Fe and inevitable impurities. According to the method, the influence of carbon and all alloy elements on hardenability, hardenability, thermal conductivity, heat resistance and linear expansion coefficient is comprehensively considered, and through low-cost alloy design and process design, the flaw detection qualification rate of base metal round steel is increased, meanwhile, the surface hardness and the average volume hardness of the grinding balls are increased, hollow grinding balls are reduced, the wear resistance of the grinding balls is improved, and the cost is reduced.

The invention relates to a silicon-molybdenum-vanadium nodular cast iron material and a preparation method and application thereof. The silicon-molybdenum-vanadium nodular cast iron material comprises the following components in percentage by mass: 2.9-3.4% of C; 3.9% to 4.3% of Si; mn: 0.1%-0.3%; less than or equal to 0.05% of P; s: less than or equal to 0.02%; 0.03% to 0.055% of Mg; 0.9% to 1.15% of Mo; 0.25% to 0.45% of V; cr: 0.1% to 0.25%; 0.008%-0.02% of RE (rare earth); and the balance of Fe and inevitable impurities. The tensile strength of the material at the temperature of 800 DEG C is 60-65 MPa, the ductility of the material at the temperature of 800 DEG C is 30%-45%, the linear expansion coefficient of the material at the temperature of 800 DEG C is 16-19 micrometers / (m.K), the material is low in cost, and the risk that the exhaust manifold of the heavy-duty engine loses efficacy and cracks under extreme conditions can be reduced.

The invention relates to the technical field of high polymer material ingredients, and discloses a low-linear expansion coefficient PCR-PP bumper material and a preparation method thereof.The low-linear expansion coefficient PCR-PP bumper material comprises a low-expansion inorganic core, an interface gradient coupling agent and a surface activity modifier, the interface gradient coupling agent forms a brush-like topology grafting layer with the grafting rate of 2.5%-4.5% on the surface of the low-expansion inorganic core, and the surface activity modifier forms a brush-like topology grafting layer with the grafting rate of 2.5%-4.5% on the surface of the low-expansion inorganic core; the surface activity regulator performs steric hindrance locking on the brush-like topological grafting layer through long-chain alkyl of the surface activity regulator. According to the preparation method, a gradient distribution interface layer with specific grafting density and chain segment length is constructed on the periphery of an inorganic core, so that an interface chain segment actively absorbs thermal expansion displacement of a matrix by utilizing conformation transformation; the thermal stress vector discontinuity between the filler and the matrix is eliminated, and an interface mechanical response mode is reconstructed to inhibit interface delamination and microcrack initiation while the overall linear expansion coefficient is inhibited.

To provide a strain gauge capable of reducing a difference in a resistance temperature coefficient as the entire strain gauge.SOLUTION: A strain gauge comprises: a first resistor; a first base material having a first surface in which the first resistor is formed and a second surface that opposes the first surface in a thickness direction; and a second base material having a third surface adhered to the second surface directly or indirectly and a fourth surface that opposes the third surface in a thickness direction. The first base material and the second base material are different each in terms of a first coefficient of linear expansion relative to a first direction orthogonal to a thickness direction and a second coefficient of linear expansion relative to a second direction orthogonal to a thickness direction and orthogonal to the first direction, and the first base material and the second base material are adhered overlappingly such that the first coefficient of linear expansion is larger than the second coefficient of linear expansion in the first base material and the second coefficient of linear expansion is larger than the first coefficient of linear expansion in the second base material.SELECTED DRAWING: Figure 2

The centrifugal fan of the present invention suppresses the displacement of the center of gravity position associated with thermal deformation. The centrifugal fan (1) includes a first portion (40) provided on a rotor (5) and a second portion (50) provided on a fan portion (3), wherein the second portion (50) has a larger linear expansion coefficient than the first portion (40). The first portion (40) includes a first top portion (42) and a first cylindrical portion (43). The second portion (50) includes a second top portion (52) and a second cylindrical portion (53). The second cylindrical portion (53) includes an inner cylindrical surface (53f) that is opposed to the outer cylindrical surface (43f) of the first cylindrical portion (43) with a first gap (S1) therebetween. The first top portion (42) includes a first plane (42f), and the second top portion (52) includes a second plane (52f) that is opposed to the first plane (42f). A convex portion (60) is provided on the first top portion (42) or the second top portion (52). The first plane (42f) and the second plane (52f) are bonded and fixed by an adhesive (G) provided in a second gap (S2) formed by the convex portion (60).

The application belongs to the technical field of polymer composites, and discloses a low linear expansion coefficient polyphenylene sulfide composite material, a preparation method and application thereof. The composite material comprises 20-60 parts of polyphenylene sulfide resin, 40-80 parts of a low expansion filler system, 0.5-5 parts of a coupling agent, 0.1-1 part of a lubricant and 0.1-1 part of a toning agent. The low expansion filler system is at least two of a lamellar structure filler, a fibrous structure filler and a nano-sized filler. The polyphenylene sulfide composite material obtained has a low linear expansion coefficient while maintaining good mechanical properties through the limiting effect of the lamellar structure filler on the thermal expansion of the resin matrix, the reinforcing effect of the fibrous structure filler on the strength and modulus of the material and the improvement effect of the nano-sized filler on the filling structure and the interface state. The polyphenylene sulfide composite material can be applied to the fields of precision instruments, electronic packaging, electronics and electrical appliances, automobiles and aerospace, etc. which have high requirements for thermal dimensional stability.

A lens unit (100) is provided with a first lens barrel member (20), a second lens barrel member (30) held on the inner peripheral side of the first lens barrel member, a cylindrical spacer (40) disposed on the inner side of the first lens barrel member and made of a material having a higher linear expansion coefficient than the first lens barrel member and the second lens barrel member, and an annular elastic member (50) disposed on the inner side of the first lens barrel member. When the temperature of the lens unit increases, the spacer thermally expands in the optical axis direction, thereby pressing the second lens barrel member toward the object side in which the elastic member is disposed, and the second lens barrel member (30) moves toward the object side in which the elastic member is disposed as the elastic member is compressed in the optical axis direction. When the temperature of the lens unit drops, the elastic member restores in the optical axis direction as the spacer is thermally shrunk in the optical axis direction, and the second barrel member moves toward the image side in which the spacer is disposed as the elastic member restores in the optical axis direction.

The invention provides a glass substrate material and hard disk substrate glass formed by the glass substrate material, the glass substrate material contains 38%-63% by mole of SiO2, 12%-22% by mole of Al2O3 and 5%-32% by mole of MgO; the sum of the molar percentages of SiO2, Al2O3 and MgO is less than or equal to 100%. The glass substrate material has one of the following characteristics: i) Tg is 640-820 DEG C; ii) an elastic modulus of from 85 to 130 Gpa; iii) the Hv is in the range of 480 to 2000 kgf / mm < 2 >; and iv) the linear expansion coefficient at 30-380 DEG C is 25-64 * 10 <-7 > / k. Compared with a traditional hard disk substrate material, the glass substrate material disclosed by the invention is higher in strength and thermal stability and better in scratch resistance and wear resistance, and can meet harsh requirements of high-capacity and high-performance hard disks.

This invention relates to the field of polymer materials technology. It discloses a low-linearity polypropylene-talc composite material, its preparation method, and its applications. The material comprises the following raw materials in weight percentages: polypropylene resin: 50-65%, modified talc: 15-25%, ethylene-octene copolymer resin: 10-15%, modified flat glass fiber: 5-15%, basic magnesium sulfate whiskers: 3-10%, heat stabilizer: 0.3-1%, and antioxidant: 0.1-0.5%. This composite material exhibits advantages such as a low coefficient of linear expansion, excellent surface tension, and superior mechanical properties.

A case of a keyboard instrument includes a lower case formed from a resin material which is a first material and extended long in a left-right direction which is a first direction, plural reinforcement members (a first reinforcement member, a second reinforcement member) fixed to the lower case, made from a sheet of steel which is a second material whose linear expansion coefficient is smaller than a linear expansion coefficient of the first material, and disposed to be divided in the left-right direction, a front case formed in such a manner as to extend long in the first direction and fixed to each of the plural reinforcement members, and side cases (a left side case, a right side case) disposed adjacent to the front case and fixed to ends of the reinforcement members.

The present application relates to the field of polyolefins, in particular, to a polypropylene resin, a polypropylene resin composition and respective preparation methods thereof. The polypropylene resin comprises: (a) component A: 60-80 wt%, a high crystalline homopolymer polypropylene, the isotactic pentad fraction of which is greater than or equal to 96%; (b) component B: 20-40 wt%, an ethylene-propylene elastomeric copolymer, the ethylene-propylene elastomeric copolymer containing 50-70 wt% ethylene structural units and 30-50 wt% propylene structural units, based on the total weight of the ethylene-propylene elastomeric copolymer; the molar fraction of ethylene / ethylene / ethylene sequences EEE in the polypropylene resin is not less than 15%; the ratio of the melt mass flow rate of the component A and the polypropylene resin under the action of a 2.16 kg load at 230℃ is 1.5-3.5:1. The final polypropylene resin composition has the characteristics of low shrinkage, high modulus, high heat distortion temperature and low linear expansion coefficient.

The present application relates to the field of diesel engine piston forging, in particular to a diesel engine piston material, a diesel engine piston and a preparation method and a forging die thereof. The diesel engine piston material provided by the present application comprises the following components: Si: 14.1-18.3 wt%; Ni: 1.6-3.2 wt%; Fe: 0.8-1.6 wt%; Mg: 0.3-0.6 wt%; Cr: 0.01-0.05 wt%; Zn: 0.06-0.3 wt%; Ti: 0.02-0.2 wt%; Zr: 0.07-0.2 wt%; V: 0.1-0.18 wt%; Al: balance. The piston material is applied to piston preparation, the layered temperature of the forging part is maintained during the forging process, the deformation and forming performance of the piston material is improved, the linear expansion coefficient is reduced, the volume stability is improved, the thermal deformation amount is reduced, and the service life of the piston is improved.

The utility model discloses a solar straight-through heat collecting tube, which relates to the technical field of straight-through heat collecting tubes, and comprises a straight-through heat collecting tube and a metal expansion joint, the metal expansion joint is tightly sleeved on the straight-through heat collecting tube, the metal expansion joint is provided with a valve which can be sealed with the straight-through heat collecting tube in a melting way, and the metal expansion joint is tightly sleeved on the straight-through heat collecting tube. The metal expansion joint is provided with a valve part capable of being sealed with the straight-through heat collecting pipe in a fusion mode, the valve part has the linear expansion coefficient similar to that of silicon-boron hard glass, the curie point is high, good low-temperature structure stability is achieved, and the pipe explosion phenomenon caused by direct sealing of the straight-through heat collecting pipe and the metal telescopic corrugated workpiece can be reduced through the valve part.

The invention discloses an embedded ceramic matrix composite turbine outer ring for an aero-engine in the technical field of aero-engine parts, and the embedded ceramic matrix composite turbine outer ring for the aero-engine comprises a turbine case, a plurality of turbine outer rings are arranged in the turbine case, the plurality of turbine outer rings are circumferentially distributed, and the turbine outer rings are arranged in the turbine case. A special-shaped bolt is arranged between the turbine outer ring and the turbine case, and the special-shaped bolt and the turbine outer ring are correspondingly arranged. By arranging the special-shaped bolt and spring composite connection structure, the problem that the connection mode is poor in connection reliability in application of the ceramic matrix composite is solved, firstly, the special-shaped bolt is matched with the limiting groove, and the pre-compression spring is combined to form elastic constraint; the continuous elastic force of the spring counteracts the thermal deformation stress caused by the difference of linear expansion coefficients of the CMC and the high-temperature alloy, meanwhile, working vibration is restrained, rigid collision between the turbine outer ring and the casing is avoided, and the blade tip gap fluctuation risk is remarkably reduced.

The present invention addresses the problem of obtaining an integrally molded article of a cylindrical section or a columnar section of a thermosetting resin and a metal member in a lightweight and stable joined state. The present invention for solving the above problem is an integrally molded article in which a metal member (b) and a structural member (a) substantially formed from a fiber-reinforced thermosetting resin are joined, the metal member (b) having an overlap region that overlaps with the structural member (a), at least a portion of the overlap region has a joint portion that is in contact with the structural member (a), and at the joint portion, the ratio ([alpha] tb / [alpha] ta) of the linear expansion coefficient [alpha] tb of the joint circumference of the metal member (b) to the linear expansion coefficient [alpha] ta of the joint circumference of the structural member (a) in a measurement temperature range of 60-150 DEG C ([alpha] tb / [alpha] ta) is 1.0-50.

A liquid discharge head includes a nozzle plate, a piezoelectric element substrate, a functional substrate, and a common channel substrate. The nozzle plate has multiple nozzles to discharge a liquid in a discharge direction. The piezoelectric element substrate is bonded to the nozzle plate. The piezoelectric element substrate includes: multiple individual chambers; a diaphragm; and multiple piezoelectric elements on the diaphragm. The piezoelectric element substrate has: a first linear expansion coefficient; and bending portions disposed at each end or at each corner of the piezoelectric element substrate. The bending portions bend in the discharge direction. The functional substrate has a first face bonded to the piezoelectric element substrate. The common channel substrate is bonded to a second face opposite to the first face of the functional substrate. The common channel substrate has a second linear expansion coefficient larger than the first linear expansion coefficient of the piezoelectric element substrate.

A lower inhaul cable is composed of the carbon fiber cables, the carbon fiber cables have the advantages of being light in weight, high in tensile strength, small in linear expansion coefficient and good in corrosion resistance, the stress performance of the lower inhaul cable can be effectively improved, the service life of the lower inhaul cable can be effectively prolonged, the lower inhaul cable and an upper rigid structure form a unilateral tensioning matching structure, and therefore the tensile strength of the lower inhaul cable is improved. Tensioning prestress can be conveniently applied, and the stress performance and the structural stability of the chord supporting structure are improved.

The invention belongs to the technical field of wood-plastic plates, and particularly relates to a PE wood-plastic composite material and a preparation method thereof. The carbon beads are introduced into a PE wood-plastic formula system to replace traditional calcium powder / talcum powder, a lubricant, an antioxidant and other raw materials, and meanwhile, through the synergistic effect of HDPE and LDPE in different proportions, on one hand, the problem of precipitation caused by lubricating components is solved, on the other hand, various mechanical properties of the PE wood-plastic composite material are improved, and the service life of the PE wood-plastic composite material is prolonged. Wherein the minimum concentrated load can be increased to 30%, the linear expansion coefficient and the shrinkage rate can be reduced by 40%, the vicat softening point can reach 127 DEG C, and the technical problems that the PE wood-plastic composite material is large in precipitation amount and prone to deformation in application are solved.