1096 results about "Low melting point" patented technology

A process or method for manufacturing a fire-retardant treated wood composite board or panel, such as oriented-strand board, with a low melting point fire retardant (FR) material, such as boric acid, while the press is operating at typical press temperatures above the FR material melting point. An intervening overlay is applied to the top surface of the mat on the forming line, after the use or application of any FR material within or on the mat, prior to entry into the press. The intervening overlay covers the top surface so as to prevent the melting fire retardant material from contacting the press platen(s). After pressing, the intervening overlay may be removed from the top surface by sanding, buffing, or other methods. The intervening overlay also may be sized so as to extend over one or more edges of the underlying panel, for ease of removal post-process.

The invention discloses a method for synchronously reducing hysteresis loss and eddy-current loss of a FeSiAl magnetic powder core, which comprises the following steps: preparing a salt solution of metal M which is low-melting-point metal with atomic radius unequal to that of Al atoms and can form a replacement solid solution with Al; adding the salt solution into the FeSiAl magnetic powder core, drying to obtain an insulated and coated magnetic powder core, and then adding a binder and a lubricant to prepare magnetic powder to be formed; and performing compression molding on the to-be-molded magnetic powder, and performing heat treatment to obtain the magnetic powder core. The low-melting-point M atoms are diffused into the FeSiAl matrix and occupy Al vacancies, lattice distortion can be reduced in the annealing process, and therefore coercive force and magnetic hysteresis loss are reduced; more importantly, after the FeSiAl is doped with the M atoms, the resistivity of the matrix is increased, eddy-current loss in the particles can be effectively inhibited, meanwhile, the Al2O3 coating layer generated through in-situ oxidation can effectively isolate the eddy-current loss among the particles, and therefore the magnetic hysteresis loss and the eddy-current loss are synchronously reduced through the method.

The invention provides ceramic polyolefin as well as a preparation method and application thereof, and belongs to the technical field of functional materials. The ceramic polyolefin provided by the invention is prepared from the following raw materials in parts by mass: 40-60 parts of polyolefin resin which is a mixture of polyethylene and an ethylene-octylene copolymer; 40-60 parts of porcelainized powder, wherein the porcelainized powder is a mixture of silicon dioxide, boric oxide, zinc oxide and magnesium oxide; 20-40 parts of low-melting-point glass powder, wherein the melting point of the low-melting-point glass powder is 400-600 DEG C; 15 to 60 parts of silicate filler; and 0.1 to 3 parts of an antioxidant. The ceramic polyolefin provided by the invention has excellent tensile strength and elongation at break, and a ceramic shell is complete.

The invention discloses low-melting-point antibacterial alkali-free glass and a preparation method thereof, and relates to the technical field of glass. According to the technical scheme, the anti-bacterial coating is prepared from, by mass, 60%-75% of silicon dioxide, 3%-13% of aluminum oxide, 3%-6% of boric acid, 1.5%-5% of magnesium oxide, 0.7%-7.5% of carbonate, 0.5%-3% of nitrate, 0.01%-0.5% of tin oxide, 0.1%-5% of titanium trifluoride and 0-1% of anti-bacterial enhancer. According to the invention, the problems of high melting point and large energy consumption of traditional TFT substrate glass raw materials are solved, the requirements of the market on the antibacterial property of the TFT substrate glass are met, and an innovative technical solution is provided for the electronic glass manufacturing industry.

The invention discloses a porous ceramic filter for liquid magnesium alloy purification and a preparation method thereof, and the porous ceramic filter comprises the following raw materials in percentage by mass: 70-85wt% of ceramic particles, 8-15wt% of multi-element oxide system microcrystalline glass brazing filler metal and the balance of a binder, al2O3-B2O3-SiO2-MgO-CaO multi-element oxide system microcrystalline glass brazing filler metal is adopted, under the condition of air atmosphere high-temperature calcination, a compact reaction layer containing a low-melting-point glass phase, an aluminum oxide phase, a magnesium aluminate spinel phase, a calcium aluminosilicate phase, a borate phase and a silicate phase is generated on the surfaces of ceramic particles of a porous ceramic filter through a chemical reaction; the magnesium alloy filter has high strength and good high-temperature stability, and the problems that the filter loses efficacy and magnesium alloy melt is polluted due to the fact that the filter is eroded by magnesium alloy liquid are effectively solved.

The invention discloses an AlScN device with low working voltage and low leakage current and a preparation method of the AlScN device. The device comprises a bottom electrode layer, a functional layer and a top electrode layer which are stacked in sequence, the functional layer comprises an AlScN ferroelectric material, and the bottom electrode layer is in ohmic contact with the functional layer; the top electrode layer is made of low-melting-point metal with the melting point lower than 200 DEG C, and part of the low-melting-point metal element is diffused and permeated into the functional layer. According to the invention, the low-melting-point metal is used as the top electrode, the working voltage and leakage current of the top electrode can be remarkably reduced, and preferably, the low-melting-point metal is melted and diffused and permeated into the functional layer through annealing treatment to form good contact and permeation doping with the functional layer, so that deep modification of electrical properties of the functional layer is formed; the working voltage and the leakage current of the AlScN-based ferroelectric memory device can be further reduced at the same time, and the AlScN-based ferroelectric memory device has far-reaching significance for the development of the AlScN-based ferroelectric memory device.

The invention relates to the technical field of part manufacturing, in particular to a hollow non-straight section composite part which is characterized in that a low-melting-point alloy is used for manufacturing a core mold to serve as a forming inner mold, fiber prepreg is laid on the surface of the core mold and subjected to curing treatment to form a shell structure, finally, the inner mold is removed in a melting mode, and the hollow non-straight section composite part is obtained. According to the hollow non-straight composite material part manufacturing method, the characteristic that materials can be controllably removed is utilized, the mold design is greatly simplified, the manufacturing cost is reduced, and meanwhile the forming freedom degree of a complex geometric structure is improved.

The invention discloses a preparation method of a low-melting-point borosilicate glass high-temperature binder. According to the invention, the borosilicate glass (B2O3.SiO2) high-temperature binder with nano-scale particles is prepared by a sol-gel method, and due to high surface energy and low melting temperature of the nano-scale particles, the melting and bonding temperature of the binder is obviously reduced while the lower content of diboron trioxide (B2O3) is maintained; the invention provides the preparation method of the high-temperature adhesive which has both high-temperature resistance and low-temperature adhesive property. The low-melting-point borosilicate glass high-temperature binder prepared by the invention has excellent low-temperature bonding performance and can keep a stable bonding effect in a high-temperature environment; therefore, the composite material has a wide application prospect in a high-temperature application scene, for example, the composite material plays an important role in connection and packaging of high-temperature parts; the low-melting-point characteristic of the binder is beneficial to reduction of energy consumption and cost in the production process, so that energy consumption is reduced.

The invention belongs to the technical field of 3D printing materials, and particularly relates to an interlayer reinforced composite material, a preparation method thereof and application of the interlayer reinforced composite material as a 3D printing material. A copolymerization group is introduced into polyaryletherketone, so that polyaryletherketone has a unique molecular structure and can compete with folding of an ether ketone chain segment in the crystallization process, in this way, in-situ copolymerization polyaryletherketone has a lower crystallization rate compared with polyether-ether-ketone or a polyether ketone system, the healing time of adjacent fused filaments of a 3D printing product is prolonged, and the 3D printing quality is improved. Compared with a conventional 3D printing material, the 3D printing material has the advantages that the interlayer strength is effectively improved and the interlayer reinforcing effect is achieved due to the long healing time, the interlayer performance of a 3D printing product obtained by using the 3D printing material is good, the tensile strength is 120-130 MPa, the interlayer tensile strength is 20-30 MPa, and the application range is wider. The interlayer reinforced composite material provided by the invention has the advantages of lower melting point, favorable processability, favorable mechanical properties, favorable high-temperature resistance and excellent comprehensive properties.

The present invention provides a method for manufacturing a non-fired brick whereby reductions in corrosion resistance and creep resistance due to the generation of low melting point substances can be suppressed, and sufficient strength can be exhibited. In the present invention, water is added to and mixed with a refractory raw material formulation containing 0.2-15 mass% of magnesia having a particle diameter of less than 75 μm and 0.3-10 mass% of silica having a particle diameter of less than 44 μm, with the remainder being mainly one or more of an alumina raw material, an alumina silica raw material, a silica raw material, and a spinel raw material, and the total content ratio of alkali metal phosphates and alkali metal silicates being less than 1 mass% (including 0). Thereafter, the mixture is press molded and then left standing at room temperature or heat treated at a temperature of 1000°C or less.

The invention provides a fault indication device of a lightning arrester and the lightning arrester. The fault indication device comprises a target resistor, a low-melting-point alloy, a counterweight and a shell, the target resistor, the low-melting-point alloy and the counter weight are all located in the shell; the first end of the target resistor is connected with a shell of the lightning arrester, the second end of the target resistor is grounded, the upper end of the low-melting-point alloy is in fixed contact with the target resistor, and the lower end of the low-melting-point alloy is connected with the balance weight; the shell comprises a visual subarea at the bottom; the target resistor generates different heat according to the magnitude of the leakage current of the lightning arrester, and when the temperature of the target resistor is higher than the melting point temperature of the low-melting-point alloy, the low-melting-point alloy is melted, and the counterweight falls into the visual partition. According to the device, by triggering melting of the low-melting-point alloy, advanced visual early warning can be provided before the lightning arrester breaks down, and the problem that fault indication of the lightning arrester is not timely is solved.

The invention provides a thermal response self-ceramization fireproof coating and a preparation method thereof. The thermal response self-ceramization fireproof coating is prepared from the following raw materials in parts by mass: 3 to 10 parts of acrylic monomer, 3 to 10 parts of organic sulfonate, 1 to 4 parts of silane coupling agent, 0.5 to 3 parts of silicate ester, 4 to 6 parts of ceramic precursor, 3 to 6 parts of fluxing agent and 0.05 to 0.4 part of initiator. The fluxing agent comprises a component A and a component B, the component A is one of boric oxide, zinc borate or low-melting-point glass powder, and the component B is one of phosphorus pentoxide and ammonium polyphosphate. The silane coupling agent can be copolymerized with an acrylic monomer to construct a C-C main chain, the C-C main chain and silicate ester are subjected to hydrolytic condensation to form a Si-O-Si three-dimensional network, a chemical cross-linked skeleton is formed, and the chemical cross-linked skeleton can generate silicon dioxide at high temperature to participate in a ceramization reaction; the ceramic precursor and silicate ester can form a strong physical cross-linking effect, so that the fireproof coating with a chemical and physical double-cross-linked network can be formed, and the fireproof coating has excellent mechanical property and machinability at normal temperature.

The invention discloses a high-CTI (comparative tracking index) flame-retardant polycarbonate composite material which comprises the following components in parts by weight: 70-80 parts of polycarbonate; 8-12 parts of a phosphate flame retardant; 3-7 parts of low-melting-point glass powder; 7-15 parts of titanium dioxide; and more than or equal to 80 mol% of end groups in the polycarbonate are terminated. Through cooperation of the phosphate flame retardant, the low-melting-point glass powder and the titanium dioxide, 1.5 mm V-0 flame retardance and even 1.0 mm flame retardance can be achieved on the premise that fluorine-containing anti-dripping agents such as PFAS are not contained and low filler filling is achieved, and meanwhile the CTI larger than or equal to 600 V is achieved.

A protection device includes a meltable conductor, an electrode set, and a heating element. The meltable conductor has a core metal layer and a bottom covering layer with low melting point. The core metal layer has a first low melting point metal layer, a second low melting point metal layer, and a high melting point metal layer laminated therebetween. The bottom covering layer with low melting point is disposed on a bottom surface of the core metal layer. The electrode set has a first electrode and a second electrode respectively connected to two terminals of the meltable conductor. The heating element is disposed under the bottom covering layer, thereby heating up and blowing the meltable conductor in the event of over-voltage.

An oxyide dispersion-strengthened (ODS) alloy is disclosed that is compatible with melt-based additive manufacturing processes, such as laser powder bed fusion (L-PBF) while achieving material properties, such as resistance to frictional ignition, comparable to or better than wrought ODS alloys. This is accomplished, in part, by adjusting the composition of the ODS alloy and / or adjusting the operating parameters of the additive manufacturing process to reduce or, in some instances, mitigate dispersoid coarsening and slag formation. For example, a nickel (Ni)-based ODS alloy may include less than 0.3 wt % aluminum (Al) to reduce the formation of low melting point oxides that are prone to coarsening and slag formation. In another example, various processing parameters associated with a selective laser melting process, such as beam power, beam spot size, and scan speed, may be chosen to reduce a melt time associated with the additive manufacturing process.

The invention belongs to the technical field of brazing materials, and particularly relates to micro-nano particle reinforced nickel-based ultralow-melting-point wear-resistant brazing filler metal and a preparation method and application thereof. The invention provides micro-nano particle reinforced nickel-based ultralow-melting-point wear-resistant brazing filler metal. The micro-nano particle reinforced nickel-based ultralow-melting-point wear-resistant brazing filler metal comprises 94-99 parts of ultralow-melting-point nickel-based brazing filler metal and 1-6 parts of micro-nano particles. The ultralow-melting-point nickel-based brazing filler metal contains B, Si, In, Sn and Cu elements at the same time, and the melting temperature of the brazing filler metal can be cooperatively reduced; and meanwhile, the micro-nano particles are added, so that the strengthening and abrasion increasing effects on the nickel-based brazing filler metal can be effectively guaranteed, and meanwhile the flowability of the brazing filler metal is not affected. Therefore, through component design of the nickel-based brazing filler metal and synergistic cooperation of the micro-nano particles, the melting point of the brazing filler metal can be remarkably reduced, the brazing filler metal can be endowed with excellent hardness and wear resistance, and the technical bottlenecks that traditional nickel-based brazing filler metal is high in melting temperature and poor in wear resistance and brazed diamond is subjected to thermal damage are solved; and the method has a wide application prospect in brazing of diamond tools.

The utility model discloses a forming tool for a variable cross-section composite material barrel. The forming tool comprises a first end cover, a second end cover, an upper die and a lower die, wherein the upper die and the lower die are provided with molded surfaces matched with the outer surface of the variable cross-section composite material barrel; and the composite core mold is provided with a molded surface matched with the inner surface of the variable cross-section composite material barrel, the composite core mold is located in a cavity defined by the upper mold, the lower mold, the first end cover and the second end cover, and a cavity used for forming the variable cross-section composite material barrel is defined by the upper mold, the lower mold and the composite core mold. The integral male die is made of low-melting-point alloy, thermal damage of high temperature to the composite barrel is avoided, secondary machining of the molded surface of the male die is not needed, the molded surface is smooth, the manufacturing period is short, and the comprehensive cost is low.

The invention discloses a method for preparing an ultrahigh-temperature ceramic coating by an ultrahigh-temperature metal gas source based on a molten salt medium, which comprises the following steps of: mixing low-melting-point salt A, metal fluoride and metal M to obtain a mixture C, putting the mixture C into a first crucible, mixing low-melting-point salt B and metal M to obtain a mixture D, putting the mixture D into a second crucible, putting a carbon base material into a deposition furnace, and performing vacuum drying to obtain the ultrahigh-temperature ceramic coating. Heating the first crucible to melt the mixture C to obtain a melt E, and heating the second crucible to melt the mixture D to obtain a melt F; carrier gas is guided into the first crucible, the carrier gas flow passes through the melt E to form gas flow containing a metal gas source, the gas flow containing the metal gas source is guided into the second crucible, and the gas flow containing the metal gas source is filtered by the melt F in the second crucible to form a pure metal reaction gas source, and finally, a pure metal reaction gas source is introduced into the deposition furnace for deposition of the carbon base material, and the ultra-high-temperature ceramic coating is obtained. The method is easy to operate and low in cost.

The invention provides an ordered platinum alloy catalyst, a preparation method and a fuel cell, and belongs to the field of fuel cells. Comprising an inner core, the inner core is a compound of PtMM * alloy and C, M is non-noble metal, and M * is low-melting-point metal; the shell covers at least part of the surface of the inner core, and the shell is a carbon layer. The low-melting-point metal element is added into the ordered platinum alloy catalyst firstly, so that the ordering transformation temperature can be reduced, finally, the ordered alloy can be obtained through heat treatment at the low temperature, and agglomeration and growth of alloy particles are avoided to the maximum extent. And secondly, carbon coating is formed on the outer layers of the PtMM * alloy particles, so that sintering, agglomeration and growth of the metal particles are effectively avoided in the heat treatment process. And finally, the carbon-supported platinum alloy catalyst is prepared by coupling the carbon-supported platinum alloy catalyst and the carbon-supported platinum alloy catalyst, and agglomeration and growth of Pt alloy can be avoided in the process of forming an ordered structure by the Pt alloy catalyst, so that a relatively small and uniform particle size is ensured.

The invention relates to the technical field of cutting tools, in particular to a solid sweating bionic tool, a dry type cutting cooling method and a manufacturing process. The cutter body is provided with a cutting edge area and is made of a matrix phase material, a bag-shaped hair-fixing phase material is doped into the matrix phase material of the cutting edge area, the melting point of the hair-fixing phase material is lower than that of the matrix phase material, a part of the hair-fixing phase is exposed on the surface layer of the matrix phase, and a part of the hair-fixing phase is embedded into the surface layer of the matrix phase; the hair fixing phase can be heated to form an air film covering the surface of the cutter, and the air film can prevent cutting heat from being transmitted to the cutter and can form phase change heat dissipation when the air film is broken. The sweating structure is designed in the blade area of the cutter, a dynamic gas film is formed through gasification phase change heat absorption of a low-melting-point material, accurate cooling of the core cutting area is achieved, the service life of the cutter is prolonged, and meanwhile use of cutting fluid is avoided.

The invention discloses a method for improving the bending strength of a neodymium-iron-boron magnet, which comprises the following steps: (1) according to the proportion of Al < x > Cu < y > Ga < z > Re < (1-x-y-z) >, smelting metal raw materials into a repair alloy, and Re refers to a rare earth element; x ranges from 0.005 to 0.3, y ranges from 0.01 to 0.5, and z ranges from 0 to 0.1; the repair alloy is smashed to be made into alloy powder with the particle size being 3-50 micrometers; mixing the alloy powder with an organic solvent and glue to prepare alloy slurry; and (2) coating the surface of the magnet substrate or an easy-to-crack area with alloy slurry, drying a solvent, then carrying out vacuum high-temperature repair treatment at 500-700 DEG C, carrying out heat preservation for 0.5-10 hours, cooling, and then carrying out tempering treatment, so as to obtain the magnet with improved bending strength. The Al-Cu-Ga-Re alloy adopted by the invention has the characteristics of low melting point and good magnet wettability, cracks in the magnet can be repaired, the magnetic performance of the magnet is not influenced, the bending strength of the magnet is improved and reaches 400 MPa or above, the risk of fragmentation of the magnet in the use process is effectively reduced, and the service life of the magnet is prolonged.

The invention discloses a large-size high-performance R-T-B rare earth permanent magnet and a preparation method thereof. The thickness of the magnet in the orientation direction is 4-14 mm; the residual magnetism Br of the large-size high-performance magnet is greater than or equal to 14.0 kGs, and the coercive force Hcj is greater than or equal to 23.0 kOe. When the magnet base body is prepared, a layered powder laying mode is adopted, so that the surface layer of the magnet is made of single alloy easy to diffuse, the core part of the magnet is made of double alloy, it is guaranteed that the core part of the magnet has high coercive force, meanwhile, the grain boundary diffusion capacity of the surface layer of the magnet is optimized, and the advantages of the double alloy and grain boundary diffusion are fully combined. Besides, an alloy of a low-melting-point metal element M2 and a heavy rare earth element RH in a certain proportion is adopted as an auxiliary alloy and a grain boundary diffusion source, the diffusion depth of the heavy rare earth element RH is promoted, excessive enrichment of the heavy rare earth element RH in a small area is prevented, and generation of body diffusion is inhibited. According to the method, the coercive force of the magnet is remarkably improved, meanwhile, it is guaranteed that the magnet has high residual magnetism, and the large-size high-performance R-T-B rare earth permanent magnet is prepared.

The invention discloses an aluminum-based composite material and a preparation method thereof. The preparation method comprises the following steps: firstly, mixing powder of an intermediate alloy, a simple substance metal and a reinforcement with a binder, and carrying out cold pressing to form a green body; degreasing and sintering the green body to obtain a sintered part; and heating the sintered part, performing closed die forging, performing heat treatment and fine trimming to obtain a finished product, and if the performance does not meet the requirements, performing hot extrusion on the sintered part, and performing heat treatment and fine trimming to obtain the finished product. Oxide is removed through ball milling, the surface of the Al-Mg powder is activated, and passivation is protected through a binder; a reinforced phase SiC is designed to be blended with a binder, and then the mixture is mixed with other powder to form a specific microstructure; low-melting-point Sn is introduced to limit the sintering temperature, element diffusion is promoted through a liquid phase, and generation of a harmful intermediate phase is avoided; a sintered part with the density being 80-95% is adopted, a low-strain soft area is formed around a reinforced phase in cooperation with a specific microstructure, deformation coordination is improved, meanwhile, the peak aging time of the aluminum alloy is prolonged through SiC, the electric conduction and heat conduction performance is improved, and the comprehensive performance of the composite material is comprehensively improved.

The invention relates to the technical field of ceramic silica gel foam aerogel preparation, and discloses a ceramic silica gel foam aerogel sheet and a preparation method thereof. Comprising the following raw materials in parts by weight: 10-30 parts of aerogel powder, 10-30 parts of glass powder, 10-30 parts of one or a mixture of calcium silicate / mica powder / kaolin / wollastonite, 20-30 parts of aluminum hydroxide, 30-50 parts of hydroxyl silicone oil, 100 parts of organosiloxane, 0.1-0.5 part of a catalyst, 20-30 parts of hydrogen-containing silicone oil and 1-5 parts of color paste, the aerogel is silicon dioxide aerogel powder, the density is 1.5 MG / ML, the pore diameter is 10-50 NM, and the pore diameter is 10-50 NM. The glass powder is low-melting-point ceramic powder, and the particle size of the glass powder is 1-20 UM. The preparation method is simple, the process is easy to control, and the quality is stable. The prepared silica gel foam aerogel internally contains a uniform closed pore structure, so that the thermal insulation and sound insulation effects are greatly improved; the rebound resilience is good, and the gap filling effect of a current aerogel product is improved.

The invention belongs to the technical field of thermal power heating surface treatment, and provides a gradient functional composite coating applied to a boiler heating surface and a preparation method of the gradient functional composite coating in order to solve the technical problems that an existing protective coating of the boiler heating surface is prone to abrasion and oxidation and high in cost. Collaborative design is formed, and gradient matching of mechanical properties and environmental failure resistance is achieved. The low-melting-point glass powder is combined with the rare earth catalytic effect, low-temperature ceramization is achieved, and thermal damage to a matrix is avoided. After the metal ceramic transition layer is sprayed, high-frequency induction remelting treatment is carried out, meanwhile, laser cladding is carried out on the surface of the ceramic surface layer, a nanocrystalline-amorphous composite structure is formed, and the bonding strength of the coating is improved.

The present invention discloses a low-power metal soft magnetic composite material and a preparation method thereof. The main components of the material are Si and Fe, and the preparation process is ingot casting, coating diffusion, crushing and screening, pressing and forming, and annealing. The advantage is that by coating and diffusing a low-melting point, high-resistivity, and easily oxidizable substance to the FeSi alloy grain boundary, not only the overall resistivity of the material is improved, but also the coating layer is evenly and stably coated on the surface of the grain, tightly combined, not easy to fall off, and can effectively avoid the problem of the insulating layer easily falling off and decomposing and failing in the subsequent pressing and annealing process. Finally, a low-power metal soft magnetic composite material is obtained by this method.

A treatment method for enhancing coercive force of neodymium iron boron magnet includes the following steps: subjecting the neodymium iron boron magnet to electrochemical deposition in a diffusion water-based solution to obtain a neodymium iron boron magnet containing a heavy rare earth; and subjecting the neodymium iron boron magnet containing the heavy rare earth to heat treatment to complete enhancement of the coercive force of the neodymium iron boron magnet. The raw material used in the present invention is cheap heavy rare earth compounds which increases the selection of diffusion sources and lowers costs. Metal alloy particles are mainly obtained in a nanoscale size and can effectively enter crystal grains, and low-melting-point metal alloy components can enhance a demagnetizing coupling effect between main phase grains. According to the present invention, the coercive force of the magnet is increased by nearly 30%, and residual magnetism is almost not changed.

The invention provides a low-melting-point PET short fiber, and relates to the technical field of fiber production. The low-melting-point PET short fiber comprises a high-strength low-melting-point PET short fiber, the short fiber is of a skin-core composite structure, a skin layer of the skin-core composite structure is modified low-melting-point polyester and is prepared by melt copolymerization of PET, 10-30% of rigid comonomers and 5-15% of flexible chain segments, the melting point is 110-160 DEG C, and the glass-transition temperature (Tg) is larger than or equal to 60 DEG C. The gradient interface enhancement technology is adopted, the PET-g-PE grafting layer is introduced between the skin layer and the core layer, the grafting rate reaches 5-8% through melt blending, a transition layer of 1-3 microns is formed, the peel strength is improved to 1.5 N / cm or above, and the problem of interface stripping of traditional composite fibers is solved.

The invention discloses a method for improving performance of rare earth permanent magnet sintered neodymium iron boron grain boundary diffusion, and belongs to the technical field of rare earth permanent magnet materials. The method comprises the steps that a low-melting-point metal layer and a diffusion layer containing heavy rare earth elements are sequentially formed on the surface of a clean sintered neodymium-iron-boron magnet, and then vacuum diffusion heat treatment and tempering treatment are conducted. Wherein the low-melting-point metal layer comprises at least one of copper, aluminum, gallium and tin or an alloy of the copper, the aluminum, the gallium and the tin; the heavy rare earth element comprises at least one of dysprosium, terbium, holmium and gadolinium. The low-melting-point metal layer is preferentially diffused and wets the grain boundary in the heat treatment process, heavy rare earth elements are promoted to be deeply and uniformly diffused towards the interior of the magnet along the grain boundary, so that a heavy rare earth-rich shell layer is formed outside main phase grains of the magnet, and the intrinsic coercive force is improved; meanwhile, the low-melting-point metal forms a strengthening phase at the grain boundary, the brittleness of the magnet after diffusion is improved, the surface corrosion phenomenon is restrained, and collaborative optimization of the comprehensive performance of the magnet is achieved.

The invention discloses a low-melting-point glass-based inorganic anticorrosive coating with excellent conductivity and a preparation method of the low-melting-point glass-based inorganic anticorrosive coating. The inorganic anticorrosive conductive coating material comprises 80-99.5 parts of a glass base material and 0.5-20 parts of conductive phase powder dispersed in the glass base material, wherein the conductive phase powder adopts a conductive oxide; the preparation process comprises the following steps: 1) mixing glass base materials; 2) melting into molten glass; 3) crushing and introducing a conductive phase; 4) sintering into blocks; 5) crushing and screening the sample; (6) preparing slurry; (7) paint spraying; and 8) sintering and cooling to obtain the paint. The method is simple in process, low in cost, corrosion-resistant, high-temperature-resistant and good in conductivity; after the conductive phase is added, the surface resistivity of the coating is reduced to 102-109 ohms, and the minimum value of the surface resistivity is far higher than that of an existing system.