166 results about "Solderability" patented technology

The invention discloses a solar cell with alloy as a flexible substrate and a preparation method thereof, a kovar alloy sheet is used as the flexible substrate to be bonded with an epitaxial layer, the coefficient of thermal expansion of the kovar alloy sheet is similar to that of an epitaxial material, and dark cracks of the epitaxial layer caused by cold and hot temperature difference are avoided; moreover, the metal bonding layer adopts a thick-silver thin-gold structure taking silver as a substrate, so that the production cost is greatly reduced, and the weldability of the back electrode is enhanced; and the back electrode also adopts a thick silver and thin gold structure taking silver as a substrate, so that the front warping of the Kovar alloy sheet can be balanced, the weldability of the back electrode is enhanced, the drawing force of the back electrode is improved, the thin gold plated on the thick silver can also prevent silver oxidation and resist the impact of atomic oxygen, and the service life of the solar cell is prolonged.

The invention discloses a fabricated steel-UHPC external prestressing combined box girder and a construction method and application thereof, and relates to the technical field of bridge engineering, the fabricated steel-UHPC external prestressing combined box girder comprises a prefabricated steel-UHPC combined top plate, a prefabricated steel-UHPC combined bottom plate, a prefabricated steel-UHPC combined web plate, a steel diaphragm plate and an external prestressing system. The box girders are formed by combining prefabricated slabs, the prefabricated web plates are firmly connected with the prefabricated top plate and the prefabricated bottom plate through welded steel plates and post-poured UHPC, and arrangement and tensioning of external prestress are achieved by arranging steel anchor boxes and steering gears in box chambers. According to the combined box girder, the steel and the UHPC are combined to form a structural form that the steel plate is wrapped by the UHPC, and the advantages of high strength, high durability, high toughness, high compactness, low creep and the like of the UHPC and the advantages of high strength, high elastic modulus and weldability of steel are fully utilized, so that the box girder has the advantages of being excellent in structural stress performance, light in overall weight, good in durability, small in later-stage deformation, low in cost and the like. And the hoisting device is especially suitable for bridges in urban rail transit or urban railways.

The invention relates to an aluminum alloy material and a preparation method thereof.The aluminum alloy material comprises Mn, Si, Fe, Cr, a first component, rare earth and Al, and the first component comprises at least one of Ti, B, Zr, V and Be; according to the total mass of the aluminum alloy material being 100%, Mn is smaller than or equal to 4%, Si is smaller than or equal to 3%, Fe is smaller than or equal to 3.5%, Cr is smaller than or equal to 6%, the mass fraction of the first component is 1%-2%, and the mass fraction of the rare earth is 7%-12%. The aluminum alloy material provided by the invention has excellent solderability, die-casting property and corrosion resistance, and can meet the requirements of complex part manufacturing and high-reliability connection.

The present invention discloses a solderability testing mechanism, comprising: a test table, a soldering trough and a solder pot located on the test table, a liquid level sensor and a solder height sensor located on the side of the solder pot; the liquid level sensor is used to measure the liquid level of the solder pot, and the solder height sensor is used to measure the height of the position to be soldered in the workpiece; a mobile module located above the test table, the mobile module being provided with a fixed clamp for clamping the workpiece; and a controller communicatively connected to the liquid level sensor, the solder height sensor, and the mobile module. The present invention provides a solderability testing mechanism and method that can accurately control the depth of tin immersion in a workpiece, thereby standardizing solderability testing standards and improving the accuracy of solderability testing.

The application belongs to the technical field of welding materials, and discloses a preformed soldering sheet and a preparation method thereof, the preparation method comprising: a flux preparation method, wherein benocyclobutene resin, a thixotropic agent, an active agent, a surfactant, an antioxidant, a corrosion inhibitor and a solvent are weighed, mixed and heated and stirred to mix, and then cooled to obtain the required flux; a processing method of a preformed soldering sheet body soldering strip, wherein lead-free filler metal is melted at high temperature to form a soldering strip; and a preformed soldering sheet preparation method, wherein the soldering strip is uniformly coated with the flux by a coating machine, and the flux is cured and attached to the soldering strip after baking; the preformed soldering sheet is obtained by the above preparation method. The application realizes improved welding quality of the soldering sheet coated with the flux film and solder metal oxidation resistance, and the preformed soldering sheet has high stability, good wettability and good weldability, and can meet the requirements of the market for the use of the preformed soldering sheet with low cavities.

The utility model discloses a capacitor service life test clamp, and relates to the technical field of capacitor detection, the capacitor service life test clamp comprises a clamping box with one end provided with an opening, a clamping structure is arranged in the clamping box, and four corners of the upper and lower surfaces of the clamping box are fixedly connected with connecting rods. Through cooperative arrangement of the clamping box, the first clamping hole, the clamping plate, the second clamping hole, a spring and other structures, during use, the clamping plate is pushed to enable the first clamping hole and the second clamping hole to be aligned, the middle section of the capacitor penetrates through the first clamping hole and the second clamping hole, the clamping plate is loosened, the clamping plate moves under the action of the elastic force of the spring, and the capacitor is clamped. The inner walls of the first clamping hole and the second clamping hole clamp the capacitor from the two sides, the end of the capacitor is not subjected to clamping acting force, and it is avoided as much as possible that when a traditional test clamp fixes the capacitor, certain pressure is applied to the two ends of the capacitor, oxidation or falling off of a tin coating at the end of the capacitor is likely to be accelerated, weldability of the capacitor is reduced, and the service life of the capacitor is prolonged. And the reliability of the capacitor is influenced.

The invention relates to a filling material for 6XXX series aluminum alloy and a welding process of the filling material, and belongs to the technical field of aluminum alloy. The filling material comprises the following elements in percentage by mass: 0.5 to 2.00 percent of Si, 0.80 to 2.00 percent of Mg, 0.20 to 3.00 percent of Cu, 0.20 to 0.50 percent of Cr, 0.50 to 0.80 percent of Mn, 0 to 0.10 percent of Ti, 0.15 to 2.00 percent of Zn, 0 to 0.15 percent of Fe and the balance of Al and other inevitable impurities, and the total impurities are 0 to 0.15 percent. The filling material has good weldability, promotes a precipitation strengthening mechanism, has the same strengthening element composition as a 6XXX series aluminum alloy base material, can be applied to welding of the 6XXX series aluminum alloy in multiple welding modes, reduces dilution of weld joint strengthening elements, and can effectively improve the mechanical properties of a joint weld joint and a heat affected zone at the same time.

The invention discloses a titanium alloy with high strength, high plasticity and toughness and a weldable structure. The titanium alloy is a Ti-Al-Mo-V-Cr-Zr series beta-rich type two-phase titanium alloy. According to the titanium alloy, the composition of the titanium alloy is controlled, the synergistic effect of high-strength contribution of Al and Mo, plasticity and toughness guarantee of V and Nb, structure optimization of Cr and Zr and low-oxygen cleanliness control is exerted, the multi-performance balanced type high-strength, high-plasticity and high-toughness weldable structure titanium alloy is obtained, and after heat treatment, the tensile strength Rm of the titanium alloy is larger than or equal to 1100 MPa, the ductility A of the titanium alloy is larger than or equal to 15%, the fracture toughness KIC of the titanium alloy is larger than or equal to 80 MPa.m < 1 / 2 >, and the impact toughness KV of the titanium alloy is larger than or equal to 40 J; and the welding seam strength matching coefficient is 0.9 or above, collaborative optimization of high strength, high plasticity and toughness, weldability and environmental adaptability is achieved, and therefore the structural mass is reduced, the service life is prolonged, integrated manufacturing is facilitated, and the high-strength and high-toughness alloy is suitable for key components in the industrial field and extreme working condition engineering scenes.

The invention discloses a printed circuit board manufacturing method for improving the reliability and weldability of a buried copper block, and the method comprises the following steps: processing a depth control blind groove in a PCB core board, and processing a groove hole with a corresponding shape in a prepreg; an embedded copper block is provided, a glue flowing groove is machined in the side wall or / and the bottom of the embedded copper block, and a protective pit is machined in the welding face of the embedded copper block; a frame type carrier is provided, a plurality of positioning grooves which are distributed in an array mode and matched with the copper blocks in shape are formed in the carrier, and the copper blocks with the size smaller than 80 mm * 80 mm are correspondingly placed in the positioning grooves of the carrier to be subjected to browning treatment; laminating the core plate and the prepreg according to a design sequence, embedding the copper block into the blind groove, and ensuring that the welding surface with the protective pit faces upwards; vacuum pressing is conducted, the glue flowing groove is filled with the molten prepreg, part of the molten prepreg flows into the protective pit, and the area, except for the protective pit, of the welding face of the embedded copper block is cleaned; and drilling, copper deposition electroplating and pattern transfer are carried out. According to the manufacturing method of the printed circuit board, the problems that in the prior art, buried copper blocks are poor in combination reliability, and solderability is not guaranteed are solved.

The invention relates to an easy-to-form corrosion-resistant and wear-resistant steel plate for a conveying pipeline and a manufacturing method thereof, and belongs to the field of pipeline steel. The surface Brinell hardness of the wear-resistant steel plate is 370-430 HB, the ductility is larger than or equal to 10%, the Charpy V-shaped impact energy at the temperature of-40 DEG C is larger than or equal to 30 J, d is equal to 4 t, and no crack exists after 180-degree cold bending; the martensite structure is uniform and fine, the grain size is larger than or equal to 7 grades, and the total grade of A, B, C and D fine inclusions in the structure is smaller than or equal to 2.0. And under the working condition that the pH value is 6.0-8.5, the corrosion resistance of the steel can be improved by 40% or above compared with that of Q355 structural steel. A high-cleanliness steelmaking continuous casting process, plate blank hydrogen diffusion, two-stage controlled rolling, high-temperature normalizing pretreatment, off-line quenching and tempering are adopted, control is conducted from the aspects of chemical component design, base metal structure and the like, and the low-temperature toughness, formability, corrosion resistance and weldability of the wear-resistant steel plate for the conveying pipeline are guaranteed; and a solution is provided for the application of the long-service-life wear-resistant pipeline.

The present invention relates to a filler material for 6XXX series aluminum alloys and its welding process, belonging to the technical field of aluminum alloys. The elemental composition and its mass percentage of the filler material are as follows: Si 0.5% - 2.00%, Mg 0.80% - 2.00%, Cu 0.20% - 3.00%, Cr 0.20% - 0.50%, Mn 0.50% - 0.80%, Ti 0 - 0.10%, Zn 0.15% - 2.00%, Fe 0 - 0.15%, the balance being Al and other inevitable impurities, with a total impurity of 0 - 0.15%. This filler material has good weldability, promotes the precipitation strengthening mechanism, has the same strengthening element composition as the base metal of 6XXX series aluminum alloys, can be applied to the welding of 6XXX series aluminum alloys through various welding methods, reduces the dilution of strengthening elements in the weld, and can effectively improve the mechanical properties of the joint weld and the heat affected zone at the same time.

The invention discloses a preparation method of an organic solderable protective film, which comprises the following steps: carrying out controllable micro-etching treatment on the surface of a metal substrate, so that the arithmetic mean roughness of the surface of the metal substrate is less than or equal to 0.20 mu m, and microscopic bulges on the surface of the metal substrate are of smooth hill-shaped structures; and performing preimpregnation treatment and OSP film forming treatment on the surface of the metal substrate in sequence to form the organic weldability protective film. According to the method disclosed by the invention, the uniformity of the organic weldability protective agent film layer and the reliability of high temperature resistance and chemical corrosion resistance are improved by accurately regulating and controlling the microstructure of the copper surface.

The invention belongs to the technical field of printed circuit board manufacturing, and particularly relates to a chemical tin immersion method and a tin immersion solution of a PCB (printed circuit board), the method and the solution adopt a couple replacement and autocatalytic reduction dual mechanism, and a tin-bismuth alloy layer is deposited on a copper bonding pad of the PCB by introducing a reducing agent and bismuth ions. The tin immersion solution comprises divalent tin salt, an acidic component, a complexing agent, a reducing agent, bismuth salt and an antioxidant. The thickness, the compactness and the uniformity of the tin layer are effectively improved, IMC growth is inhibited, and the weldability, the oxidation resistance and the long-term reliability of the PCB bonding pad are improved.

The application discloses a rare earth high-strength dual-phase steel and a forming method and application thereof, and belongs to the technical field of dual-phase steel. The forming method of the rare earth high-strength dual-phase steel comprises the following steps: converter smelting, LF refining, RH refining, adding cerium iron and yttrium iron at the end of the RH refining or before continuous casting, continuous casting, three-stage hot rolling, cold rolling and three-stage annealing. The rare earth high-strength dual-phase steel has good cold stamping formability, high weldability, no rare earth element segregation, no cracking of steel forming, high yield, and can be directly used to prepare automobile bodies after cold stamping forming at normal temperature. There is no rare earth inclusion or coarse carbon nitride brittle bulk agglomerate on the surface layer of the weld, the rare earth element is in a dispersed distribution state, has excellent dispersion strengthening effect, the weld is not prone to cracking, and the mechanical properties of the weld are superior to those of the base material.

The application discloses an aluminum nitride film circuit substrate and a preparation method thereof, and relates to the technical field of aluminum nitride substrates.The application is characterized by the following steps: a titanium film is plated on the surface of an aluminum nitride ceramic substrate by magnetron sputtering, and then a copper film is plated on the surface of the titanium film by magnetron sputtering; and a nickel film is plated on the surface of the copper film by a chemical plating method to prepare the aluminum nitride film circuit substrate.Through the titanium-copper gradient dynamic transition technology, a gradient alloy layer is formed to reduce the interface stress; the titanium and the surface of the aluminum nitride are combined through a chemical bond to form a dense transition layer, thereby relieving the difference in the thermal expansion coefficient; the copper enhances the conductive performance of the surface of the aluminum nitride ceramic substrate; the titanium compensates for the interface defects of the mismatch between the copper and the aluminum nitride ceramic lattice; the chemical nickel plating enhances the hardness and corrosion resistance of the aluminum nitride ceramic substrate, and the aluminum nitride film substrate is endowed with weldability and bondability.

This invention relates to the field of metallic materials technology, specifically to a high-temperature alloy for chloride molten salt heat transfer and storage, its preparation method, and its applications. Based on the total weight of the high-temperature alloy, it comprises: 20%–25% Cr, 25%–30% Fe, 1.8%–3.0% Al, 0.1%–0.5% Si, 1.5%–2.5% Ti, 3%–5% Mo, 0.5%–1% W, 0.5%–1% Mn, 0.01%–0.05% Hf, <0.1% C, and the balance Ni. The high-temperature alloy provided by this invention possesses good corrosion resistance, meeting the corrosion resistance requirements of chloride molten salt environments at 400℃–750℃. Furthermore, this high-temperature alloy also exhibits good mechanical strength, weldability, and cold and hot working properties, making it easy to process into plates and pipes.

The invention discloses a soldering flux, a low-void-rate high-lead soldering paste and a preparation method of the soldering paste, and belongs to the technical field of electronic circuit surface mounting. The soldering flux is composed of 40%-50% by weight of rosin, 0.5%-2% by weight of a defoaming agent, 6%-12% by weight of organic acid, 0.05%-0.2% by weight of haloid, 5%-8% by weight of a thixotropic agent, 1%-2% by weight of a corrosion inhibitor and the balance solvent. The soldering flux and the solder alloy powder are mixed according to the mass ratio of 1: 10 to prepare the high-lead soldering paste. The high-lead solder paste has extremely low voidage, shows good weldability in welding under the condition of meeting the halogen-free standard, is full and bright in welding spots after welding, and is particularly suitable for packaging and welding of electronic components with high voidage requirements.

This invention discloses a conductive paste for metallization of electronic ceramics, belonging to the field of electronic materials technology. The conductive paste for metallization of electronic ceramics of this invention includes copper alloy powder, glass powder, and an organic carrier. By controlling the ratio of copper, aluminum, and zinc in the copper alloy, the thermal expansion coefficient of the alloy is adjusted, making it compatible with electronic ceramic substrates such as alumina ceramics and zinc oxide varistors, achieving metallization through sintering under air conditions. The addition of tin improves the solderability of the metallized layer, meeting the process requirements of electronic components. The glass powder added in this invention has a low initial melting temperature, high bonding strength with the copper alloy, and strong adhesion to the ceramic substrate; combined with a specific ratio of organic carrier, it effectively improves the conductivity of the metallized layer after sintering.

The application discloses a semiconductor device solderability test device and a test method, which comprises an experimental box body, an experimental table is arranged in the experimental box body, a solder furnace and a flux furnace are arranged at the top end of the experimental table, and a lifting and rotating mechanism is arranged at the bottom end of the experimental table; an experimental clamp is arranged, a scale column is arranged at the top end of the experimental clamp, the scale column is attracted to the top end of the experimental clamp through an electromagnet, a weighing mechanism is connected to the top end of the scale column, and proximity switches corresponding to the solder furnace are arranged on the two sides of the experimental clamp; wherein a cleaning mechanism is arranged at the top end in the experimental box body. The weighing reading of the weighing mechanism is prevented from changing due to collision, and the accuracy of experimental results is affected; meanwhile, the depth of the semiconductor device immersed in the solder can be observed through the scale column, the lifting height of the solder furnace is adjusted, and the depth of the semiconductor device immersed in the solder is facilitated to be controlled in the experiment.

There is provided a bonding wire for semiconductor devices that exhibits a favorable bondability even when being applied to wedge bonding at the room temperature, and also achieves an excellent bond reliability. The bonding wire includes a core material of Cu or Cu alloy (hereinafter referred to as a “Cu core material”), and a coating containing a noble metal formed on a surface of the Cu core material. A concentration of Cu at a surface of the wire is 30 to 80 at %.

The invention discloses a metal powder type flux-cored wire suitable for 1500MPa-grade hot-formed steel, which is characterized by comprising a carbon steel sheath and a welding wire flux core wrapped in the carbon steel sheath, and the welding wire flux core comprises the following components in percentage by weight: 6-12% of electrolytic manganese, 6-12% of silicon carbide, 6-12% of silicon carbide, 6-12% of silicon carbide, 5-10% of silicon carbide and the balance of iron. 6%-10% of high-carbon ferromanganese; 3%-6% of chromium carbide; 18%-28% of nickel powder; 0.5%-1.5% of silicon carbide; 0.4% to 0.8% of high-purity ferrotitanium; 0.5%-1.5% of rare earth ferrosilicon; 2%-5% of ferrosilicon powder; 6%-10% of molybdenum powder; 0.2% to 0.5% of lithium fluoride; 0.1%-0.3% of titanium-boron alloy and the balance of gas atomization iron powder. The welding wire has the advantages of being good in weldability, high in tensile strength, good in crack resistance and the like. According to the mechanical properties of deposited metal, the tensile strength is larger than or equal to 1040 MPa, the yield strength is larger than or equal to 960 MPa, AKV2 at-40 DEG C is larger than or equal to 27 J, and the ductility is larger than or equal to 13%. The tensile strength of a welded joint obtained by welding 1500MPa hot-formed steel through a lap joint test is greater than or equal to 950MPa, and a fracture position is a heat affected zone of a base metal part.

A semiconductor package comprises a lead frame, a chip, and a molding encapsulation. The lead frame comprises one or more die paddles and a plurality of leads. Each of the plurality of leads comprises a base member and a protrusion member. A width of an end surface of the protrusion member of each of the plurality of leads is less than 50% of a width of a corresponding base member so as to improve solderability. A method, for fabricating semiconductor packages, comprises the steps of providing a lead frame array, mounting a chip, forming a molding encapsulation, applying a cutting process or a punching process, applying a plating process, and applying a singulation process.

The invention discloses a composite solder ball, a preparation method and a stacked packaging structure, and the composite solder ball comprises a composite inner core which is composed of a continuous phase matrix and a strengthening phase, the strengthening phase accounts for 15-30% of the total volume of the inner core, the compression modulus of the composite inner core is larger than or equal to 3 GPa, and the thermal expansion coefficient of the composite inner core is smaller than or equal to 55 ppm / DEG C; the polymer core is coated with the metal transition layer; and the tin-silver alloy outer layer covers the metal transition layer. The composite inner core is composed of a continuous phase polymer matrix and a strengthening phase fiber network, high-temperature compression resistance and low thermal expansion characteristics are achieved through a specific volume ratio and a specific mass ratio, the solid-state rigidity characteristic is kept in a welding high-temperature interval, mechanical loads are directly borne, the interlayer height collapse risk is thoroughly eliminated, and the welding quality is improved. The metal transition layer forms a mechanical interlocking combination interface with the inner core, and the tin-silver alloy outer layer provides weldability and an electric connection function, so that double-function technology fusion that the composite solder ball can play a supporting role and also can play a welding role is realized.

The invention discloses a composite metal coating without electron escape interference and a preparation method of the composite metal coating, and belongs to the technical field of metal coatings. The composite metal coating sequentially comprises a base material, a first metal conducting layer, a second metal-nonmetal composite conducting layer, a heterojunction structure layer and a third conducting layer from inside to outside. The preparation method comprises the following steps: pre-treating the base material; electrically depositing a first metal conductive layer and a second metal-nonmetal composite conductive layer in sequence; carrying out phosphating or nitriding treatment and heat treatment on the second metal-nonmetal composite conductive layer to form a heterojunction structure layer capable of effectively shielding electron migration; and finally, electrically depositing a third conductive layer. According to the heterojunction structure layer, the hybridization property of inorganic nonmetal and metal ions is utilized, a structure with high oxidation resistance and stability is formed, and electron activity migration of copper and nickel in the inner layer is effectively shielded; and the adverse effect of an intermetallic compound formed by electron migration on weldability and corrosion resistance is solved.

The invention belongs to the technical field of metal material surface treatment, and discloses a production process of a weldable electroplated chromium plate. According to the process, cluster-shaped peak morphology is transferred on the surface of a cold-rolled steel coil through a laser texturing roller, and staged double-layer chromium electroplating is combined, specifically, a discontinuous chromium layer is formed on the top of a micro convex peak through first-time high-current pulse electroplating, and local iron leakage points are reserved; the second low current direct current plating covers an ultrathin continuous chromium film to maintain macro passivation. According to the invention, a composite functional structure with both macroscopic passivation integrity and microcosmic conductive selectivity is constructed on the surface of chromium-plated iron by accurately controlling the microstructure of the surface of a base material and double-layer chromium plating process parameters, so that the technical bottleneck of the chromium-plated plate in resistance welding application is effectively solved, collaborative optimization of weldability and corrosion resistance is realized, and the application range of the chromium-plated plate in resistance welding is widened. And a reliable technical path is provided for comprehensive replacement of chromium-plated iron in the field of metal packaging.

Provided is an aluminum coated steel sheet having excellent anti-corrosion properties and weldability, and a manufacturing method thereof. The aluminum coated steel sheet includes: an austenitic base steel sheet including at least 70 area % of an austenite microstructure; and an aluminum coating layer formed on the base steel sheet, wherein the base steel sheet includes at least 80 area % of ferrite in a surface layer portion, which denotes a region extending from the interface with the coating layer to a depth of 100 μm into the base steel sheet, and the aluminum coating layer may have a composition comprising 2-12 wt % of Si, 5-30 wt % of Zn, and 0.1-5 wt % of Mn, with the balance being Al and inevitable impurities.

The utility model relates to the technical field of photovoltaic power generation, in particular to a solar cell and a photovoltaic assembly, and aims to solve the problem that a secondary grid welding area of the conventional solar cell is easy to cause welding grid breakage. Therefore, the solar cell comprises an auxiliary grid line and an auxiliary grid welding area, the auxiliary grid line is printed by adopting first metal slurry, the auxiliary grid welding area is printed by adopting second metal slurry, and the welding tension of the second metal slurry is greater than that of the first metal slurry. According to the utility model, the auxiliary grid lines and the auxiliary grid welding areas on the solar cell are printed through two different metal pastes, and the welding tension of the second metal paste used for printing the auxiliary grid welding areas is greater than that of the first metal paste used for printing the auxiliary grid lines, namely, the welding tension of the second metal paste is greater than that of the first metal paste used for printing the auxiliary grid lines. The weldability of the second metal slurry is better than the weldability of the first metal slurry, so that the welding quality of the auxiliary grid welding area can be improved, the probability of welding broken grids can be effectively reduced, and the situation of welding broken grids is avoided.

The present invention provides an ultrasonic welding method and an assembly, relating to the technical field of materials, to solve the technical problems of poor weldability and low connection strength of thermosetting composites. The ultrasonic welding method includes: disposing a layer of thermoplastic film on the surface of the thermosetting composite to be welded, and the surface of the thermoplastic film facing away from the thermosetting composite has periodically alternating recessed portions, wherein the thickness of the thermoplastic film is 0.05 mm to 0.5 mm, and the depth of the recessed portion is 0.01 mm to 0.09 mm; abutting the surface of the other workpiece to be welded against the surface of the thermoplastic film having the recessed portions; and performing ultrasonic welding on the two workpieces. The ultrasonic welding method of the present invention is used for welding between two workpieces, wherein at least one of the workpieces is a thermosetting composite, and welding can be performed without using energy guiding ribs. Not only is the connection strength high, but the welding time is short, and thermal degradation of the thermosetting composite can be effectively avoided.

To provide a Cu-Ni-Zn alloy that meets all of high proof stress, low Young's modulus, favorable solderability, low electrical conductivity, and a small difference between Young's modulus at room temperature and after heating in Young's modulus measurement using a resonance method.SOLUTION: A copper alloy contains Zn: 32 mass% or more and 45 mass% or less, Ni: more than 15 mass% and 30 mass% or less, Mn: 0.001 mass% or more and 7 mass% or less, 0.001 mass% or more and 0.45 mass% or less of at least one selected from the group consisting of Sn, Ag, Ti, Si, P, Cr, and Mg, and 0.2 mass% or less (including 0 mass%) of at least one selected from the group consisting of O, H, Bi, Pb, As, and Fe, the balance being Cu and unavoidable impurities, the alloy containing a β phase, and an arithmetic average value of an inscribed circle diameter of the β phase being less than 1000 nm.SELECTED DRAWING: Figure 1

The metal composite material comprises a working layer and a matrix layer, the working layer and the matrix layer are metallurgically bonded, and a transition area is arranged at an interface; the main component of the working layer is TiC steel bond hard alloy; the main component of the matrix layer is low-carbon steel; the invention further discloses a preparation method and application of the metal composite material. According to the metal composite material, the TiC steel bond hard alloy powder and the low-carbon steel are combined, the TiC steel bond hard alloy has high hardness and excellent wear resistance, the low-carbon steel matrix layer is easy to machine and good in weldability, and the low-carbon steel matrix layer provides impact resistance for the whole material, so that the material can bear impact loads while having high wear resistance.