120 results about "Solderability" patented technology

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 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 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 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.

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.

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.

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.

The invention discloses a fixture for electronic device solderability test, which is used for being detachably connected with solderability test equipment, the solderability test equipment comprises a working table, and the working table is provided with a solder groove capable of lifting and moving. The base is detachably connected with the working table top, the support is connected with the base in a sliding mode and can move back and forth along the base, the clamping mechanism is connected with the support through a universal connecting assembly, the clamping mechanism is used for clamping a to-be-tested device, and the position of the clamping mechanism can correspond to that of the welding flux groove. The clamping mechanism comprises a clamping space used for clamping the device and a clamping adjusting mechanism used for adjusting the size of the clamping space and clamping the device, a test is completed through the clamp, the device is directly held by hand instead of manual work, safety accidents caused by handheld operation are avoided, the size of the clamping space can be adjusted, and the device is convenient to use. And more devices with different sizes and different shapes can be clamped, and the universality is higher.

The invention relates to the technical field of metal material welding, in particular to a low-deformation high-fatigue-performance welding method for a high-strength 6-series thin-wall aluminum alloy, which comprises the following steps: S1, precision pretreatment before welding: carrying out surface cleaning and weldability protection on a groove and an adjacent area of a to-be-welded workpiece; s2, low-heat-damage double-source collaborative welding is conducted, specifically, welding is conducted through double-wire pulse consumable electrode inert gas shielded welding, and welding-following local chilling is conducted on the back face of a welding seam in the welding process; and S3, after-welding active performance regulation and control treatment is conducted, specifically, high-frequency mechanical shock treatment is conducted on the weld toe area of the weld joint cooled to the room temperature, and then local solid solution and aging composite heat treatment is conducted on the area containing the weld joint and the heat affected zone. According to the method, the welding stability is guaranteed through pretreatment, the total heat input is reduced through double-wire welding, a high-temperature area is shrunk along with welding chilling, cooperative control over welding deformation and residual stress is achieved, pressure stress is introduced through weld toe impact, a softening area is repaired through local heat treatment, and the fatigue performance of a connector is improved.

The application relates to the solder technology field, and particularly discloses a soldering material for chip packaging and a preparation method thereof, and the soldering material for chip packaging comprises the following component raw materials in percentage by weight: Ag 2-6%, Cu 0.4-1%, Al 0.05-0.2%, Cr 0.03-0.08%, CeO2 0.01-0.06%, P 0.0003-0.001% and the rest Sn, and the soldering material for chip packaging prepared by the application has the advantages of improving the solderability and the oxidation resistance of the soldering material.

The application discloses a preparation method of a bolt type piezoelectric high-temperature transducer, and belongs to the field of nondestructive testing. The silver coupling layer is prepared through the steel screen printing technology based on the pressure-free nanosilver low-temperature sintering technology. The high-temperature piezoelectric wafer is coupled / adhered to the mounting end face of the bolt through the silver coupling layer. The point gluing method is adopted to adhere the sheet electrode to the upper end face and the mounting end face of the piezoelectric wafer. The two end faces of the piezoelectric wafer, the mounting end face of the bolt and the sheet electrode are integrally plated with silver to guarantee the solderability. The excellent coupling performance of the silver coupling layer and the excellent bonding strength of the silver solder joint guarantee the reliability of the transducer working at 350 DEG C, and realize the long-term stable continuous real-time monitoring in the high-temperature environment.

The invention relates to a manufacturing method of a selective chemical nickel ceramic-based printed circuit board for a power module, and aims to solve the technical problems that a chemical nickel layer is easy to yellow and a copper surface is easy to oxidize in a subsequent process in the prior art. The method comprises the following steps: pasting a protective film and performing laser windowing on a ceramic-based copper-clad plate with a manufactured circuit for the first time, exposing an area needing chemical nickel plating, and performing chemical nickel plating; after the film is torn off, the second time of protection film pasting and laser windowing are carried out, the copper surface area needing to be treated is accurately exposed, and meanwhile the plated nickel layer is tightly covered with the protection film; and finally, carrying out anti-oxidation treatment on the exposed copper surface. The core of the invention lies in a collaborative process of two-time film pasting and laser windowing, and a film is pasted again after chemical nickel plating to protect a nickel layer, so that the nickel layer is completely isolated from acid and alkali liquid medicine in the subsequent copper surface treatment, the yellowing phenomenon of the nickel layer is fundamentally avoided, and the cleanness and weldability of the copper surface are ensured.

The invention provides conductive silver paste special for a glass-based circuit board and a preparation method of the conductive silver paste. The conductive silver paste comprises, by weight, 60-90 parts of silver powder, 4-30 parts of polymer resin, 1.5-5 parts of inorganic filler, 0.05-0.5 part of auxiliaries and 5-20 parts of solvent. The silver powder is spherical and nano silver powder; the glass powder is lead-free glass powder, and the inorganic additive filler is glass powder, indium-tin alloy powder and an expansion coefficient adjusting material (nickel sulfide); the special conductive silver paste for the glass-based circuit board, provided by the invention, has the characteristics of easiness in printing, good solderability by using a lead-free solder after sintering, long service life of a finished product, high and low temperature climate resistance, acid, alkali and salt chemical corrosion resistance, and firm adhesion with a glass substrate without falling after long-term use.

A composite material and method for producing said composite material are disclosed, with a support layer composed of a wrought aluminum alloy and with an external solder layer composed of an aluminum solder alloy provided on one or both flat sides of the support layer, wherein the solder layer has partially exposed silicon particles on its surface, which constitute a first area fraction of the total area of the surface of the solder layer. In order to reliably ensure flux-free solderability, it is proposed for the solder layer to have a rolled surface and for its aluminum solder alloy to contain at least 0.1 wt % bismuth (Bi), wherein the first area fraction is greater than 2.5%.

This invention relates to the field of intelligent manufacturing technology and provides a deep learning-based adaptive optimization method for welding process parameters. The method includes: acquiring the weld path and quality target of the parts to be welded; dividing the weld path into a set of weld segment units; collecting pre-welding geometric data and in-welding process data for each weld segment unit to obtain segment welding state characteristics; constructing a local weldability risk field to obtain segment risk field results; generating a segment parameter candidate set based on the welding parameter safety working window as a constraint and the segment risk field results; inputting the segment welding state characteristics, segment risk field results, and segment parameter candidate set into a pre-constructed physical constraint deep learning model to obtain segment quality prediction results; and performing rolling parameter optimization based on the segment quality prediction results to obtain a segment welding parameter sequence and sending it to the welding execution end.

The invention provides a simulation test method based on a non-collapse solder ball BGA device weldability test, and relates to the technical field of BGA device welding, and the method comprises the following steps: S1, solder ball water vapor aging; s2, solder ball drying: performing high-temperature baking in a dry environment; s3, solder paste is applied to the solder ball to prepare a sample, and reflow soldering is conducted on the prepared sample; a proper amount of soldering paste consistent in shape is directly printed on the non-collapse solder ball BGA solder ball through a soldering paste applying tool, and the soldering paste at least covers 50% of the surface of the solder ball; according to the invention, the whole preparation process is more convenient, and the problem of solderability test failure caused by solder ball adhesion and the like cannot be formed, so that the sample preparation efficiency and the solderability test success rate are improved, and the cost increased by preparing samples in multiple tests is also reduced; therefore, the success rate and the efficiency of the weldability test of the non-collapse solder ball BGA device are improved.