182 results about "Boriding" patented technology

The invention relates to the field of high-temperature anti-oxidation coatings, in particular to a tantalum-tungsten alloy surface high-temperature anti-oxidation composite coating and a preparation method thereof.The coating is composed of two layers of coatings with different components, the thermal expansion coefficients of the coatings and a base body are matched, the thermal expansion coefficients of the coatings are matched, and residual stress and thermal stress are reduced. The coating is prepared by adopting an embedding boriding and slurry melting method, and the used material components comprise ZrB2, MoSi2, 8YSZ, B, La2O3, Al2O3, NaF, TaSi2 and the like. The preparation method specifically comprises the following steps: putting a substrate into embedding powder for boronizing treatment, then mixing a coating material with ethanol and a binder, putting the mixture into a ball mill for wet mixing to prepare coating slurry, spraying the coating slurry on the surface of the substrate, and putting the substrate into a vacuum tube furnace for sintering to prepare a coating, thereby obtaining the high-temperature anti-oxidation composite coating. The binding force between the developed coating and the tantalum-tungsten alloy matrix is strong, and the tantalum-tungsten alloy matrix can be protected from oxidation corrosion or the oxidation rate can be slowed down within 500-2500s at the high temperature (2000 DEG C or above).

The invention provides a modified lithium iron manganese phosphate positive electrode material, a preparation method thereof and a lithium ion battery, and relates to the technical field of lithium ion battery materials. The positive electrode material comprises a phosphorus source, an iron source, a manganese source, a lithium source and a magnesium source. Mixing a titanium source solution, carrying out hydrothermal reaction, centrifugally washing and drying to synthesize the lithium manganese iron phosphate, and coating polypyrrole and a glucose carbon layer to improve the electronic conductivity of the lithium manganese iron phosphate. The magnesium-titanium co-doped stable crystal structure is introduced, the lithium ion diffusion path is shortened, the dissolution of the manganese element is inhibited, the structural change in the charging and discharging process is reduced, the side reaction with the electrolyte is inhibited by coating the cobalt boride, and the electrochemical performance of the lithium manganese iron phosphate is improved. The primary nano-particles improve ionic conductivity, and the secondary nano-particles are nano-particles formed by assembling the primary nano-particles and have the advantages of being good in rate capability, high in compaction density and high in tap density.

The invention belongs to the technical field of crystallizer copper plate surface treatment, and discloses a crystallizer copper plate surface coating preparation method, which comprises: 1) carrying out ball milling mixing on nickel powder and tungsten powder to obtain first mixed powder; (2) adding titanium boride powder and copper powder into the first mixed powder, and uniformly stirring to obtain second mixed powder; 3) performing vacuum hot pressing sintering or vacuum hot isostatic pressing sintering on the second mixed powder, and then crushing a sintered product to obtain coating composite powder; and (4) after the surface of the crystallizer copper plate base material is pretreated, the coating composite powder is sprayed to the surface of the crystallizer copper plate base material through supersonic flame spraying or plasma spraying, and the surface coating is formed. The surface coating has high hardness and wear resistance, and the interior of the surface coating and the surface coating and a crystallizer copper plate base material have good bonding performance, so that the service life of the crystallizer copper plate is greatly prolonged.

The invention provides an Al-Si series die-casting aluminum alloy based on secondary aluminum, a preparation method of the Al-Si series die-casting aluminum alloy and a structural part. The method comprises the following steps: adding industrial silicon, steel scrap and Ni into a secondary aluminum melt to obtain a mixed melt; carrying out boronizing treatment and primary refining treatment on the mixed melt; the temperature is adjusted to 710-780 DEG C, magnesium alloy waste, Sr and Al-Ti-B alloy are added, and then secondary refining treatment is conducted; and the mixed melt is subjected to die-casting treatment, and the Al-Si series die-casting aluminum alloy based on the secondary aluminum is obtained. The high-strength aluminum alloy material comprises the following components in percentage by mass: 6%-12% of Si, 0.1%-1% of Fe, 0.4%-3% of Mg, 0%-0.1% of Sr, 0%-0.3% of Ti, 0%-0.05% of B and 0%-2.5% of Ni.

The invention relates to the technical field of metal surface treatment, in particular to a method for achieving titanium metal surface rapid boronizing through electric field induction nanometer assembly in molten salt, titanium dioxide powder, boron powder, inorganic salt and a nanometer particle wrapping agent are evenly mixed, and the molten salt containing nanometer TiB2 is obtained after heating reaction. Graphite and a titanium metal part are put into molten salt containing nano TiB2, the graphite serves as a positive electrode, the titanium metal part serves as a negative electrode, the surface area ratio of the positive electrode to the negative electrode is (3-10): 1, the nano TiB2 in the molten salt is assembled on the surface of the titanium metal part under the action of an electric field to form a boronizing layer, and the boronizing speed is 60-500 microns / h. Compared with an existing high-temperature boronizing technology with active boron atoms as a constituent unit, the high-temperature boronizing technology has the advantages that the boronizing speed can be remarkably increased, the high-temperature boronizing treatment time of titanium metal is shortened, energy is saved, cost is reduced, and meanwhile the negative influence of the high-temperature environment on the organization structure and the mechanical property of a titanium metal part is eliminated.

The invention discloses a heat treatment process of an alloy drill bit, which belongs to the field of alloy and comprises the following steps: S1, after the alloy drill bit is primarily machined and formed, carrying out vacuum pretreatment, heat preservation and heating; s2, the drill bit is rapidly transferred into a sectional temperature control carburizing furnace to be subjected to main carburizing treatment, the temperature is controlled between 930 DEG C and 960 DEG C, the carburizing time ranges from 3 hours to 4 hours, and the carburizing depth is controlled between 0.3 mm and 0.6 mm; s3, after carburizing is completed, subarea multi-speed cooling is carried out, quenching is carried out for 20 seconds at the temperature of 850 DEG C or above, controlled cooling is carried out for 60 seconds within the range of 550 DEG C to 650 DEG C, slow cooling is carried out for 80 seconds at the temperature of 200 DEG C or below, and a refined martensite complex phase structure is obtained; s4, after cooling is completed, double-section tempering treatment is carried out; and S5, performing ultrahigh-pressure static boriding diffusion treatment. The method has the beneficial effects that the processing uniformity, the structure stability, the wear resistance and the corrosion resistance of the alloy drill bit are effectively improved and the service life of the alloy drill bit is effectively prolonged by adopting staged temperature control, different cooling media and a directional quenching technology.

The invention provides a preparation method of a high-wear-resistance composite coating on the surface of a GH4169 high-temperature alloy, and belongs to the technical field of wear-resistant material preparation. According to the preparation method of the high-wear-resistance composite coating on the GH4169 high-temperature alloy surface, a boronizing hard layer is formed on the surface of a GH4169 high-temperature alloy base material by adopting a chemical heat treatment solid-phase boronizing method, and on the basis, a solid lubricating Ag layer is further deposited on the boronizing hard layer by utilizing a novel ion beam assisted deposition method, so that the high-wear-resistance composite coating on the GH4169 high-temperature alloy surface is obtained. And thus, the high-wear-resistance boride / Ag composite coating is formed on the surface of the GH4169 base material. Compared with a traditional nickel-based material, the novel soft and hard composite coating can improve the binding force between a layer and a layer base, the overall quality of a film layer is improved, the friction coefficient is remarkably reduced, and high abrasion resistance is achieved.

The invention relates to the field of furnace lining materials, in particular to a rapid repairing material for a tapping hole and a furnace lining of an intermediate frequency furnace. The rapid repairing material comprises the following components in parts by weight: 50-70 parts of tabular corundum, 10-20 parts of fused magnesite, 8-15 parts of alumina micro powder, 3-8 parts of nano zirconia, 5-12 parts of silicon carbide, 10-15 parts of silica sol and 2-5 parts of a reinforcing agent. Wherein the reinforcing agent is titanium calcium aluminate coated with chromium nickel boride. The tabular corundum is mainly used as an integral framework; the fused magnesite is matched with the alumina micro powder to form magnesium aluminate spinel with a high melting point; the nano zirconium oxide can fill pores and is excellent in toughness; the silicon carbide has the advantages of high hardness, high thermal conductivity and high melting point; the reinforcing agent is titanium calcium aluminate coated with chromium nickel boride, although the adding amount is small, the high-temperature strength, toughness and thermal shock resistance of the repairing material can be remarkably improved, and especially the long-term corrosion resistance can be remarkably improved.

The invention discloses a shielding part made of a tungsten-based alloy material, a preparation method and application, the tungsten-based alloy comprises a tungsten matrix and lanthanum hexaboride dispersed in the tungsten matrix, and the content of boron in the tungsten-based alloy is 0.01 wt%-0.5 wt%. Lanthanum hexaboride is introduced into the tungsten-based alloy, so that refining of tungsten grains in the tungsten-based alloy is facilitated, the toughness of the tungsten-based alloy is enhanced, the ductile-brittle transition temperature is reduced, and the absorption capacity of the tungsten-based alloy to neutron irradiation is improved; meanwhile, the introduction of lanthanum hexaboride not only does not reduce the heat-conducting property of the tungsten matrix, but also contributes to the improvement of the heat-conducting property of the material, so that the service life of the shielding piece is prolonged.

The invention belongs to the technical field of conductor materials, and particularly relates to a creep-resistant high-strength high-conductivity aluminum alloy conductor material and a preparation method and application thereof. In the preparation process of the creep-resistant high-strength high-conductivity aluminum alloy conductor material provided by the invention, Be, Mo, Co and the like are introduced into the aluminum alloy conductor material through the intermediate alloy, and AlB3 is used for boronizing treatment; meanwhile, an expansion extrusion process is introduced between aluminum alloy continuous casting and continuous rolling processes, pre-aging treatment is carried out after solid solution heat treatment, and final aging treatment is carried out after drawing treatment; the components and the preparation process of the aluminum alloy conductor material are improved, the comprehensive performance such as conductivity, creep resistance and strength is remarkably improved, the comprehensive performance requirements of new energy automobiles on aluminum alloy conductors can be met, and the technical problem that in the prior art, the comprehensive performance of the aluminum alloy conductor material is poor is solved.

The invention relates to the technical field of metal material surface strengthening and modification, in particular to a preparation method and process of a titanium alloy laser cladding cobalt-based wear-resistant coating. The invention provides a titanium alloy surface laser cladding cobalt-based wear-resistant coating which takes titanium or a titanium alloy as a base material, comprises the following components in percentage by weight: 40-50% of cobalt (Co), 30-40% of tungsten carbide (WC), 10-15% of chromium (Cr), 1-5% of lanthanum hexaboride (LaB6), 2-5% of silicon (Si) and 0.5-3% of calcium fluoride (CaF2), and has the beneficial effects of improving wear resistance, high-temperature stability, corrosion resistance, high hardness, high bonding strength, difficulty in cracking and the like.

The invention belongs to the technical field of tungsten alloy, and particularly discloses a tungsten alloy electrode material and a preparation method thereof.The tungsten alloy electrode material comprises, by weight, 0.1%-0.2% of lanthanum boride, 0.2%-0.5% of zirconium oxide, 0.2%-0.6% of boron carbide, 0.4%-0.8% of cerium oxide, 0.5%-1.2% of tantalum carbide, 1.4%-1.8% of modified carbon nanotubes and the balance tungsten powder. The lanthanum boride, the zirconium oxide, the boron carbide, the cerium oxide, the tantalum carbide and the modified carbon nanotubes are added into the tungsten powder, under the combined action of the lanthanum boride, the zirconium oxide, the boron carbide, the cerium oxide, the tantalum carbide and the modified carbon nanotubes, the tensile strength and the electrical conductivity are effectively improved, and the high-temperature stability tungsten powder has excellent high-temperature stability and wide application prospects.

The invention relates to the technical field of battery materials, and discloses a multi-layer coated lithium-manganese-rich positive electrode material, a preparation method thereof, a positive plate and a battery. The multi-layer coated lithium-manganese-rich positive electrode material comprises an inner core, a first coating layer and a second coating layer, wherein the inner core is coated with the first coating layer and the second coating layer in sequence; the inner core is a lithium-rich manganese-based positive electrode material; the first coating layer is O2 type lithium nickel manganese oxide; the second coating layer is cobalt boride; the mass ratio of the first coating layer to the inner core is (2-11): 100; and the mass ratio of the second coating layer to the inner core is (5.3-25): 100. The preparation method comprises the step of sequentially coating the O2-type lithium nickel manganese oxide and the cobalt boride on the surfaces of the lithium-manganese-rich positive electrode material particles. The positive plate comprises the positive electrode material. The battery comprises the positive plate. According to the multi-layer coated lithium-manganese-rich positive electrode material provided by the invention, the mechanical toughness of the lithium-manganese-rich positive electrode material can be improved and irreversible phase transformation can be relieved through the cooperation of the coated O2 type material and the cobalt boride.

The invention discloses a preparation method of a nickel-iron alloy composite electrode suitable for electrocatalytic cracking of alkaline seawater and a product. The preparation method comprises the steps of surface treatment of a nickel-iron alloy sheet and preparation of a boronized nickel-iron alloy sheet composite electrode. According to the method, the marketed NiFe alloy sheet is directly subjected to thermal boronizing treatment and is directly subjected to electrochemical oxidation to prepare the multi-chromatography oxygen electrode, and various requirements of an anode material for seawater decomposition can be met. The prepared multi-layer oxygen electrode is mainly composed of a surface oxide layer, an alloy middle layer and an alloy substrate layer. The NiFeB alloy layer on the surface plays a role of a catalytic active layer, the NiFeB alloy layer in the middle plays a role of a corrosion-resistant layer, the NiFe alloy layer on the substrate plays a role of supporting, and the electrode material is efficiently supported by multiple layers together, so that the electrode material has a rapid electron transfer process, and the electrode material can show relatively high catalytic activity. The electrode material is cheap in raw material source and simple in preparation process, and has a relatively strong commercial application prospect.

The invention provides a high-compaction coated modified lithium manganese iron phosphate positive electrode material as well as a preparation method and application thereof, and relates to the field of lithium ion battery materials. The positive electrode material is prepared by the following steps: mixing a phosphorus source, an iron source, a manganese source, a magnesium source, a titanium source, a cobalt source, a lithium source, a carbon source and a dispersing agent, grinding, performing spray drying, and performing primary sintering to prepare a lithium manganese iron phosphate semi-finished product; the preparation method comprises the following steps: uniformly mixing a lithium manganese iron phosphate semi-finished product with tungsten boride, carrying out three-stage grinding including coarse grinding, coarse and fine grinding and fine grinding, carrying out batch mixing on the ground reduced slurry according to different volume ratios to improve the compaction density of the material, uniformly mixing the slurry, carrying out spray drying, and carrying out high-temperature sintering to obtain the lithium manganese iron phosphate composite material. And carrying out airflow crushing and sieving to obtain the high-compaction coated and modified lithium manganese iron phosphate positive electrode material. After tungsten boride and lithium manganese iron phosphate are coated, chemical acting force is formed on the surface, the polarization phenomenon is remarkably weakened, and the positive electrode material shows good long-term cycle stability.

The invention discloses an extrusion-molded magnesium oxide tube and a processing technology thereof, and relates to the technical field of functional ceramics, and the processing technology comprises the following steps: mixing magnesium oxide and inorganic auxiliary materials, and carrying out ball milling; adding a binder, carrying out extrusion molding, and sintering to obtain a magnesium oxide tube; the inorganic auxiliary material is a mixture of aluminum oxide and titanium boride in a mass ratio of (0.5-3.0): 1. According to the invention, by adding the inorganic auxiliary material, alumina and magnesium oxide are subjected to a solid-phase reaction to generate a magnesium aluminate spinel phase, so that the thermal shock resistance, high temperature resistance and thermal conductivity of a sintered product are improved. Introduced titanium boride can react with gas volatile matter generated by sintering of the binder, and cooperates with a sintered product of the binder to form three-dimensional ceramic among magnesium oxide particles, so that the hardness, high temperature resistance and stability of the sintered product are improved, and the heat transfer efficiency of the sintered product is improved.

The invention provides a high-toughness high-thermal-conductivity die-casting aluminum alloy, a preparation method thereof and a structural part. The method comprises the following steps: adding industrial silicon and steel scrap into a secondary aluminum melt to obtain a mixed melt; boronizing treatment and refining treatment are carried out; magnesium alloy waste, Sr, RE, Cr, Zn and Al-Ti-B alloy are added into the mixed melt, refining treatment and die casting treatment are conducted, and then the aluminum alloy is obtained. The invention relates to a high-strength aluminum alloy, which comprises the following components in percentage by mass: 6 to 11 percent of Si, 0.05 to 0.8 percent of Fe, 0.2 to 3 percent of Mg, 0.001 to 0.1 percent of Sr, 0 to 0.2 percent of RE, 0 to 0.3 percent of Ti, 0 to 0.05 percent of B, 0 to 1 percent of Zn and 0.0001 to 0.5 percent of Cr.

The invention discloses a high-mechanical-property aluminum-based composite material for shielding neutrons and gamma rays and a preparation method of the high-mechanical-property aluminum-based composite material for shielding the neutrons and the gamma rays, 6-series aluminum alloy is used as basic alloy, and tungsten boride with the volume fraction being 9-20% or mixed powder of tungsten and boron with the volume fraction sum being 9-20% is added, so that the high-mechanical-property aluminum-based composite material for shielding the neutrons and the gamma rays is obtained. The preparation method comprises the following steps: weighing raw material powder, putting the weighed raw material powder into a stainless steel tank, adding a ball milling medium and a lubricant, putting the obtained raw materials into the stainless steel tank, putting the stainless steel tank on a ball mill, carrying out vacuum ball milling to obtain a mixture, putting the mixture into a graphite mold, and carrying out hot pressing to obtain the high-strength graphite material. And heating and pressurizing in a vacuum environment or a protective atmosphere, carrying out hot pressed sintering under the conditions of heat preservation and pressure preservation, and cooling to room temperature to obtain the compact sintered block of the tungsten-boron-gadolinium-aluminum composite material. The tungsten-boron-gadolinium-aluminum composite material can achieve good neutron and gamma ray shielding at the same time, and has high application value.

The invention discloses a novel antibacterial environment-friendly ceramic and a preparation method thereof, and belongs to the technical field of ceramics, the method comprises the following steps: dissolving aluminum chloride, barium nitrate and ferric nitrate in a solvent, and stirring and mixing to prepare a first mixed solution; adding kaolin and carbon powder into the first mixed solution, and stirring and mixing to obtain a second mixed solution; boron, carbon, aluminum, boron oxide, zirconium dioxide and barium carbonate are dispersed in a dispersing agent to be mixed to prepare a third mixed solution; boron oxide, aluminum hydroxide, titanium boride, zirconium, silicon, sodium zirconate, sodium carbonate, calcium tungstate and zirconium dioxide are added into the second mixed solution to be stirred and mixed, and mixed slurry is prepared; the mixed slurry is used for preparing a blank body, the blank body is placed in a sintering furnace to be sintered in different temperature stages and sintering environments, and the prepared ceramic has high strength, is not prone to cracks in the environment where the temperature changes rapidly and is good in corrosion resistance.

This invention relates to a coating alloy, based on Iron Boride (Fe2B), a powder developed for bonding the surfaces of steels. Coatings made with the powder of this invention, using methods such as fusion or thermal spraying, provide an increase in surface hardness, wear resistance, and corrosion resistance of metallic materials, especially steels, and therefore represent a significant alternative to bonding through thermochemical methods. The alloy powder developed in this invention essentially contains iron (Fe) and boron (B) elements, with a boron (B) content between 7.1 % and 10% by weight.

The application discloses a preparation method of zirconium boride-based porous ultrahigh-temperature ceramic, and the method comprises the following steps: obtaining at least two kinds of zirconium boride powder with different particle sizes, mixing the obtained zirconium boride powder, and drying the mixed zirconium boride powder to obtain zirconium boride-based powder; the obtained zirconium boride-based powder is loosely stacked in a sintering container; the sintering container containing the zirconium boride-based powder is sintered in a protective gas atmosphere, and then zirconium boride-based porous ultrahigh-temperature ceramic is obtained. The preparation method provided by the application can quickly prepare zirconium boride-based porous ultrahigh-temperature ceramic, and the prepared zirconium boride-based porous ultrahigh-temperature ceramic has the characteristics of high compressive strength and low thermal conductivity.

The present invention relates to the field of ceramic manufacturing technology, specifically to a high-hardness alumina-based ceramic and a preparation method thereof. The high-hardness alumina-based ceramic includes the following raw materials in parts by mass: 88 to 90 parts of alumina, 5 to 7 parts of zirconium oxide, 2 to 4 parts of lanthanum boride-modified barium titanate, 1 to 3 parts of zirconium oxide-modified silicon carbide, 6 to 8 parts of sintering aids, 1 to 2 parts of polyacrylic acid, 1 to 2 parts of sodium alginate, 0.5 to 1.0 parts of triammonium citrate, and 15 to 20 parts of solvent. The sintering aid includes a composition of magnesium oxide, nano-titanium dioxide, glass powder, and niobium pentoxide. In the scheme, alumina is used as the main body, zirconium oxide is added as a toughening agent, lanthanum boride-modified barium titanate and zirconium oxide-modified silicon carbide are used as toughening agents, and a sintering aid is introduced to improve the sintering performance, effectively improve the density of alumina-based ceramics, and increase mechanical properties such as hardness and fracture toughness.

The application relates to the technical field of ceramic materials, in particular to a boron carbide composite ceramic material and a preparation method and an etching component thereof. The preparation method comprises the following steps: forming granular materials containing boron carbide, titanium boride and silicon carbide, the granular materials have a spherical structure, the mass proportion of the boron carbide in the granular materials is 70%-90%, the mass proportion of the titanium boride is 5%-25%, and the mass proportion of the silicon carbide is 5%-25%; and the granular materials are sequentially subjected to pre-sintering and hot-press sintering to prepare the boron carbide composite ceramic material; wherein the temperature of the pre-sintering is 1200 DEG C-1500 DEG C. The application can promote the three-dimensional communication growth of sintering necks in the hot-press sintering process, effectively improve the material density, ensure the good uniformity of the material, and synergistically improve the etching resistance of the boron carbide ceramic material.

The application provides a modified lithium manganese iron phosphate positive electrode material and a preparation method and a lithium ion battery thereof, and relates to the technical field of lithium ion battery materials. The positive electrode material is prepared by mixing a phosphorus source, an iron source, a manganese source, a lithium source, a magnesium source and a titanium source, and then performing hydrothermal reaction, centrifugal washing and drying to synthesize lithium manganese iron phosphate. The electronic conductivity of the lithium manganese iron phosphate is improved by coating polypyrrole and a glucose carbon layer. The application introduces magnesium and titanium co-doping to stabilize the crystal structure, shorten the lithium ion diffusion path, inhibit the dissolution of manganese elements and reduce the structural changes in the charging and discharging process. The coating of cobalt boride inhibits the side reaction with the electrolyte and improves the electrochemical performance of the lithium manganese iron phosphate. The primary nanoparticles improve the ion conductivity, and the secondary nanoparticles are nanoparticles assembled by the primary nanoparticles, which have the advantages of good rate performance, high tap density and high vibration density.

The invention belongs to the technical field of preparation of green special fire-resistant ceramics and functional coatings for continuous casting, and provides a special fire-resistant anti-adhesion ceramic coating for a boron nitride side sealing plate for thin-strip continuous casting and a preparation method of the special fire-resistant anti-adhesion ceramic coating. The preparation method comprises the following steps: forming a hollow structure by taking polymer microspheres as a template, dipping in a cerium salt solution and sintering; preparing coated zirconium boride, mixing zirconium boride with silicon dioxide powder, depositing an aluminum phosphate protective film on the surface of the mixture, and performing heat treatment and curing; compounding the boron nitride sheets and the silicon carbide nanowires, and performing surface treatment to obtain a mixed reinforcing material; the materials are prepared into three-layer slurry with a gradient function, then the boron nitride side sealing plate base body is coated with the bonding layer, the functional layer and the working layer in sequence, low-temperature pre-sintering is conducted on the multi-layer structure, and finally rapid densification of the coating is achieved through the spark plasma sintering technology. And constructing a special fire-resistant anti-adhesion functional layer taking an inorganic ceramic phase as a main body.

The present application relates to the technical field of building materials, and discloses an anti-static and radiation-proof concrete, comprising the following raw materials by weight: 250-380 parts of cement, 70-200 parts of steel slag, 500-750 parts of river sand, 600-800 parts of crushed stone, 125-190 parts of water, and 35-65 parts of additives; wherein the additives are one or two of strontium ferrite and hafnium boride. The concrete prepared by the specific proportion and specific components of the present application has excellent anti-static and radiation-proof properties.

A method for improving the wear resistance of an alloy surface, belonging to the field of alloy surface treatment, comprises: placing an alloy having a boriding agent layer on its surface in a vacuum environment, heating it to a preset temperature, and performing a boriding treatment while maintaining the preset temperature and pressure; wherein the alloy contains a transition metal element, the preset pressure is 30MPa-60MPa, and the preset temperature is 950°C-1200°C. By subjecting the alloy and the boriding agent layer to boriding treatment at high temperature and high pressure, the wear resistance of the alloy surface can be effectively improved.

This invention relates to the field of welding electrodes for duplex stainless steel, specifically to a welding electrode for duplex stainless steel and its preparation method. When residual stress at the weld seam of 2209 duplex stainless steel is eliminated through high-temperature heat treatment, the mechanical properties and corrosion resistance of the weld seam significantly decrease. To address the above technical problem, this invention provides a welding electrode for duplex stainless steel that effectively slows down the phase transformation rate during high-temperature heat treatment, avoids excessive austenite formation, and maintains the balance of the duplex structure. The electrode coating composition specifically includes lanthanum hexaboride and Ti-6Al-4V alloy, which have grain-refining effects and simultaneously inhibit the precipitation of harmful intermetallic phases. This effectively suppresses the precipitation of harmful phases such as the σ phase during weld heat treatment, ensures the solid solubility of chromium and molybdenum, and allows the weld seam to retain excellent comprehensive properties after high-temperature treatment.

The invention discloses a novel magnesium alloy and a preparation method thereof, and the preparation method comprises the following steps: 1) boronizing Mn: mixing Mn powder and B powder according to a certain proportion, fully grinding until the powder is uniformly mixed, then heating to excite the active energy of Mn and B, and boronizing Mn to obtain boronized Mn powder; 2) mixing the boronized Mn powder with aluminum powder and magnesium alloy powder in proportion, and fully grinding until the powder is uniformly mixed to obtain 'Mn (boronized) + Al' / metal matrix mixed powder; and (3) the mixed powder is subjected to solid-phase vacuum hot pressing sintering, and the Mn (boronizing treatment) + Al / metal-based material is obtained. According to the method disclosed by the invention, due to the compound addition of the boronized Mn powder and Al, the original WE43 magnesium alloy has a low thermal expansion coefficient in a high-temperature region, and the strength and plasticity of the WE43 magnesium alloy are also improved.

The application belongs to the field of ceramic materials, and particularly relates to a preparation method of a porous titanium boride alloy / hydroxyapatite fluoride composite material. 10 (PO4)6OH 2‑2x F 2x Wherein, x is 0.1-0.6; in the mixture, the weight ratio of TC4, TiB2 and FHA is 86-94:3-7:3-7; the sintering temperature is 1000-1100 DEG C. The application also includes the composite material prepared by the preparation method and the application of the composite material in oral implant materials. The preparation method can realize synergy, improve the strength and biological activity of the material based on the combination of components, proportions and sintering processes.