56 results about "Composite solder" patented technology

The invention discloses an intelligent assembly method of a precise connector, which comprises the following steps of: adding phase change particles with different melting points into tin-silver-copper-based solder according to the difference of functional areas of welding spots in the connector, generating an area formula index, and obtaining composite solder with partition identification; according to the area formula index, the composite welding flux is deposited to preset welding spot positions according to the functional areas, and particle distribution information is recorded; performing reflow soldering on different functional areas by adopting corresponding temperature curves according to the melting point parameters of the phase change particles, and recording the temperature history of each area; applying pulse thermal excitation to the packaged connector, and collecting a surface temperature change curve of each welding spot to obtain thermal response data; and performing correlation comparison on the thermal response data and process historical data, identifying the welding spot defect type according to curve deviation characteristics, and generating process adjustment parameters. According to the scheme, after the connector is completely packaged, rapid nondestructive detection of internal tiny welding spots can be realized, hidden defects can be effectively identified, and intelligent optimization and adjustment of process parameters can be realized.

The invention belongs to the technical field of brazing materials, and discloses high-entropy composite brazing filler metal and a preparation method and application thereof. The high-entropy composite brazing filler metal comprises a nickel-based brazing filler metal matrix and high-entropy alloy powder, and the high-entropy alloy powder comprises, by atomic percent, 15%-25% of Co, 15%-25% of Cr, 15%-25% of Fe and 25%-45% of Ni. According to the high-entropy composite brazing filler metal, the low melting temperature is kept, the high-entropy alloy particles can adjust joint residual stress caused by the large difference of thermal expansion coefficients of dissimilar materials, the interface regulation and control effect is achieved, generation and distribution of joint brittle phases are affected, a special core-shell structure is formed around the high-entropy particles, and therefore the high-entropy composite brazing filler metal can be obtained. A continuous brittle phase formed by a joint can be broken, crack propagation is prevented, the mechanical property of the joint is remarkably improved, the brazing filler metal preparation method is simple and easy to implement, and the high-entropy composite brazing filler metal adopts an instantaneous liquid diffusion brazing mode, so that weld joint structure components are homogenized.

The invention discloses a preparation method and application of a low-temperature photovoltaic welding strip, and belongs to the technical field of energy conservation and environmental protection. According to the technical scheme, the method comprises the steps that a metal precursor is dissolved in an alcoholic solution, and a nano reinforced phase is prepared through regulation and control of a surfactant, ultrasonic treatment and aging calcination; the composite solder is prepared through argon smelting according to 1-6 parts of Sn, Bi, Ag, Ni, Cu, Ge, the modified glass powder and the nano reinforced phase; 99.95% electrolytic copper is subjected to vacuum melting and cold rolling to form a copper strip; the surface roughness is controlled through alkali washing degreasing and acid washing micro-etching; immersing the preheated copper strip into a molten pool for plating; and carrying out heat preservation and rosin protection treatment. According to the method, low-temperature welding at the temperature of 150-220 DEG C is achieved, an Ag-Sn intermetallic compound layer is formed after welding, the pull-off strength retention rate of a welding spot is larger than or equal to 80% after 200 times of thermal cycles, and the method is suitable for interconnection of crystalline silicon photovoltaic battery pieces.

The invention provides an electronic speed regulator capacitor installation structure and an installation method thereof. The electronic speed regulator capacitor installation structure comprises a main circuit board, a transition circuit board and a capacitor. The main circuit board is provided with a first through hole, and a reinforced bonding pad is formed at the first through hole; a second through hole is formed in the transition circuit board, a golden finger type bonding pad is arranged at the lower end of the transition circuit board, the golden finger type bonding pad is electrically connected with the second through hole, and the golden finger type bonding pad of the transition circuit board penetrates through the first through hole and forms a composite welding spot through welding; a plurality of capacitors are arranged along the length direction of the transition circuit board. Pins of the capacitors are vertically inserted into the second through holes and form composite welding spots through welding. The capacitor mounting structure of the electronic speed regulator is easy to produce, high in tensile strength and high in mechanical and electrical performance reliability.

The invention relates to active composite brazing filler metal suitable for welding ceramics and copper materials and a preparation method of the active composite brazing filler metal. The active composite brazing filler metal is composed of a plastic matrix layer and an active coating. The plastic matrix layer is a metal foil containing at least one of Ag, Cu and Ni; the active coating is an active metal layer arranged on the plastic matrix layer, and active metal is selected from at least one of Ti, Zr, Cr, Hf, V and Nb. The active coating is divided into two layers, the upper layer is a TiH2 active metal layer, and the lower layer is a TiH2 active metal layer. The metal foil is an AgCu28 foil, and the active coating is a TiH2 active brazing filler metal. The preparation method of the active composite brazing filler metal comprises the steps that S1, the metal foil and the active composite brazing filler metal paste are prepared; s2, the metal foil is coated with the active composite brazing filler metal paste; and S3, baking is conducted in the environment of 80-150 DEG C, and the active composite brazing filler metal is formed. The method is simple, reasonable, high in efficiency, low in cost and high in reliability.

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 application discloses a MAX phase reinforced three-dimensional network tin-based lead-free solder and a preparation method thereof, and belongs to the technical field of lead-free solder. The MAX phase reinforced three-dimensional network tin-based lead-free solder is characterized in that the MAX phase reinforcing phase is distributed in the form of a three-dimensional continuous network skeleton at the grain boundary of a tin-based lead-free solder matrix; and the MAX phase reinforcing phase forms a continuous network penetrating through the whole tin-based lead-free solder matrix. The application also discloses an application of the MAX phase reinforced three-dimensional network tin-based lead-free solder in a high-temperature, high-load and high-frequency vibration scene. Through process innovation and performance optimization, the application aims to finally prepare a "high-strength, high-plasticity and high-temperature stability" tin-based three-dimensional network composite solder, solves the problem that a traditional tin-based single-component lead-free solder is prone to deformation and cracking due to thermal stress and mechanical load, improves the reliability of electronic packaging, and expands the application range of the tin-based lead-free solder in high-demand fields.

The production process of the photovoltaic V-shaped composite welding strip comprises the steps of prefabrication of an alloy copper strip, prefabrication of an alloy aluminum strip, prefabrication of alloy calcium powder and synthesis and mold pressing processes. The prefabricated alloy calcium powder, the alloy aluminum strip and the alloy copper strip are compounded and subjected to mould pressing through a synthesis mould pressing process, and the inclined grain V-shaped composite welding strip with inclined grains on the A surface is synthesized; the sloping grain V-shaped composite welding strip is subjected to surface cleaning, tin plating on the surface B and silver plating on the surface A to obtain the photovoltaic V-shaped composite welding strip. The photovoltaic V-shaped composite solder strip has the beneficial effects that the photovoltaic V-shaped composite solder strip manufactured by adopting the production process is low in cost, high in conductivity, low in failure rate, low in use and maintenance cost and long in service life; the cost of photovoltaic products can be reduced, application and popularization of the photovoltaic products are promoted, and immeasurable beneficial effects are brought to development of ecological energy and environmental protection.

The application discloses a preparation method of a high-reliability core-shell composite solder capable of low-temperature welding, and belongs to the technical field of welding materials of electronic components. The core-shell composite solder is made of Sn-based solder powder by means of rolling plating, and a series of Sn-Bi low-temperature alloy plating layers are plated on the surface of the solder powder. The core-shell composite solder powder is produced in batches by changing the type and size of the commonly used Sn-based solder in the core to plate a series of Sn-x Bi low-temperature solder alloy plating layers on the shell, so as to produce core-shell composite solder powders of different sizes and types and composite BGA solder balls. The composite solder powder is suitable for the preparation of solder paste capable of low-temperature reflow and high-temperature service, and the composite BGA solder ball can be directly used for solder balls capable of low-temperature reflow and high-temperature service, so that the types and usability of the composite solder at the present stage are greatly improved, and the welding reliability is improved. Compared with the alloy solder prepared by the traditional melting and casting method, the method has the advantages of simple process, low cost and easy operation.

The invention belongs to the technical field of semiconductor welding, and particularly relates to a high-reliability solder structure and a processing method and equipment thereof, the high-reliability solder structure comprises lead-free solder and a high-melting-point metal block, the lead-free solder is selected from one or more combinations of Sn-based solder and In-based solder, and the high-melting-point metal block is selected from one or more combinations of Sn-based solder and In-based solder. The high-melting-point metal block comprises pure metals of Cu, Ni, Ag and Zn and alloys thereof, and a protective layer of pure metals of Sn and In and alloys thereof can be arranged on the surface of the high-melting-point metal block; due to the fact that the height limiting block with the high melting point is arranged in the composite solder, control over the height is more accurate. After the welding flux is melted, the welding flux does not flow around under the action of surface tension.

The application is suitable for the technical field of solar cells, and provides a composite solder strip, a cell string, a cell module and a photovoltaic system. The composite solder strip comprises a first solder strip, an insulating strip and a second solder strip. The first solder strip, the insulating strip and the second solder strip extend along a first direction and are arranged in contact with each other along a second direction. The first solder strip comprises a first conductive piece and a plurality of first insulating pieces. The first insulating pieces are arranged on the first conductive piece and are distributed at intervals along the first direction. The first conductive piece is exposed between the adjacent two first insulating pieces to form a first cell connecting area. In this way, since the first solder strip and the second solder strip are integrated together through the insulating strip, the arrangement frequency of the solder strip can be reduced. Since the first solder strip comprises the first insulating pieces arranged at intervals, the first conductive piece is exposed between the adjacent two first insulating pieces to form the first cell connecting area, and thus the operation of insulating the solder strip from the non-corresponding grid lines one by one can be omitted. Therefore, the connection step of the solder strip and the cell piece can be simplified.

A photovoltaic V-shaped composite solder strip comprises an alloy copper sheet layer, an alloy aluminum shell layer, an alloy calcium powder layer, soldering tin, a rectangular solder groove and a twill V-shaped groove, the alloy aluminum shell layer is a rectangular shell, and the alloy calcium powder layer is filled in the middle of the alloy aluminum shell layer; the periphery of the alloy aluminum shell layer is coated with an alloy copper sheet layer; four sides of the alloy copper sheet layer are provided with edges; a sloping grain V-shaped groove is formed in the surface A; the surface B is provided with a rectangular solder groove; the middle part of the surface B is provided with alloy copper sheet layers on two sides welded by soldering tin; the left side face and the right side face of the alloy copper sheet layer are smooth faces parallel to each other. The beneficial effects are that the device is low in cost, high in conductivity, low in fault rate, low in use and maintenance cost, and long in service life; the cost of photovoltaic products can be reduced, application and popularization of the photovoltaic products are promoted, and immeasurable beneficial effects are brought to development of ecological energy and environmental protection.

The utility model is suitable for the field of photovoltaic technology, and provides a composite welding strip, a back contact solar cell module and a photovoltaic system. The second conducting layer is arranged on the outer surface of the first conducting layer, the first conducting layer comprises aluminum, and the second conducting layer comprises copper; the connecting layer is arranged between the first conductive layer and the second conductive layer, and the yield strength of the composite welding strip is greater than or equal to 45MPa and less than or equal to 75MPa. According to the invention, the yield strength of the composite welding strip is controlled within a preset range, so that the problem that the composite welding strip is easy to warp to cause the warping of a battery piece can be avoided, and the battery piece yield strength is improved. Compared with a traditional copper solder strip, the cost is greatly reduced, and the production cost of a battery assembly is effectively reduced.

The invention relates to the technical field of semiconductor welding, in particular to a composite welding flux capable of being matched with different thermal expansion coefficients and a rolling technology. According to the composite welding flux, an iron-nickel alloy middle layer is used, and the thermal expansion coefficient of the composite welding flux can be adjusted within the range of 1.4-12 * 10 <-6 > K <-1 > according to the nickel content; the solder can meet the working requirement of a wide bandgap semiconductor material at the high temperature of 200-450 DEG C, and is obviously superior to a traditional tin-based solder and a high-lead solder. Due to the invar effect of the iron-nickel alloy middle layer, the thermal expansion coefficient of the iron-nickel alloy middle layer is highly matched with novel semiconductor materials such as SiC, SiN and GaN, welding joint cracks caused by the difference of the thermal expansion coefficients are effectively avoided, and therefore the problem that due to the fact that the thermal expansion coefficients of existing welding flux are not matched, the welding joint cracks is solved.

The invention relates to the technical field of battery manufacturing, in particular to a stress self-adaptive interconnection method and device for a thin film battery array based on a flexible PCB, and the method comprises the steps: processing and forming a micro-groove array on the surface of the PCB, and preparing a composite solder structure; collecting a real-time deformation field and a bonding pad position of the PCB, and generating a compensation mounting path of the thin film battery; the contact force between the thin film battery and the bonding pad is controlled to be smoothly increased; performing local thermal ultrasonic solid-phase bonding on the electrode on the thin film battery and the corresponding bonding point on the PCB; performing laser irradiation on the lower electrode of the battery and the PCB bonding pad to form a high-melting-point intermetallic compound; collecting three-dimensional shape geometric parameters of the welding spots, extracting efficiency distribution and defect characteristics of the battery, and dynamically adjusting process parameters of the upflow according to the efficiency distribution and defect characteristics; and calculating residual stress distribution, and dynamically adjusting pressure applied to different areas by a hot pressing roller in a subsequent packaging process. According to the invention, the large-scale and high-reliability manufacturing of the flexible PCB-based thin film solar wing can be effectively realized.

The invention relates to the technical field of ceramic substrates, and provides a high-heat-conductivity metal brazing copper-clad ceramic substrate and a preparation method thereof. The high-heat-conductivity metal brazing copper-clad ceramic substrate comprises a ceramic base body, composite solder and a copper sheet from bottom to top, and the composite solder is composed of, by weight, 20%-25% of Cu, 1%-5% of Ti, 1.4%-3.5% of active components and the balance Ag; the active components comprise Nb, Hf and Ta. According to the technical scheme, the problem that in the prior art, a metal brazing copper-clad ceramic substrate is low in heat conductivity is solved.

The application belongs to the technical field of solder processing, and discloses a composite solder piece and a preparation method thereof. The composite solder piece comprises a first low-melting-point solder layer, an Ag-based intermediate layer, a second low-melting-point solder layer and a solder coating which are stacked in sequence; wherein the first and second low-melting-point solder layers comprise a rare earth element-doped Ag-Cu-Sn alloy, and the Ag-based intermediate layer comprises a silver-based alloy doped with 0.5%-3% In and 0.1%-1.5% Ga elements. The design reduces the melting point of the intermediate layer by In / Ga doping to realize overall low-temperature brazing, and utilizes the rare earth element to refine grains and strengthen the interface, thereby synergistically improving the high-temperature strength and thermal fatigue resistance of the brazed joint. The outermost solder coating can improve wettability and provide oxidation resistance protection. The application significantly reduces the connection temperature while improving the high-temperature strength and wettability of the brazed joint, thereby ensuring excellent high-temperature reliability and process adaptability of the joint.

The application relates to the technical field of semiconductor packaging, in particular to a SnBi low-temperature hot-press bonding method and structure based on elastic microsphere enhancement, which comprises the following steps: S1, preparing SnBi-based composite solder paste containing metalized elastic microspheres, wherein the metalized elastic microspheres are uniformly distributed in the composite solder paste; S2, coating the composite solder paste to the pads of a substrate through a printing process; S3, aligning and placing a chip on the solder paste, and then preheating the chip through a heating head; S4, applying vertical pressure to the chip through the heating head and heating the chip to above the melting point of the composite solder paste, implementing hot-press bonding, so that the solder paste melts and the metalized elastic microspheres are compressed; and S5, forcibly cooling under the condition that the vertical pressure applied to the heating head is kept unchanged, and after the solder solidifies, the heating head removes the pressure, and the bonding is completed. Through the application, the problem that SnBi low-temperature solder joints are prone to brittle fracture and the problem that solder overflow leads to short circuit of the pads can be overcome.

The invention discloses a high-reliability medium-temperature composite solder and a preparation method thereof.The high-reliability medium-temperature composite solder comprises an alloy base material and a composite material, and the alloy base material comprises, by mass, 65-85 parts of Sn, 10-30 parts of In, 0.5-3 parts of Ag, 0.5-3 parts of Bi, 0.5-1.2 parts of Cu and 0.1-0.2 part of other metal elements; wherein the other metal elements comprise one of Sb, Ge, Co and Ni; the composite material comprises the following components in parts by mass: 0.1-1.0 part of nano copper powder used for inhibiting migration and remelting of an In-rich phase and forming a solid solution strengthening phase; and nano graphene powder. By means of the mode, according to the high-reliability medium-temperature composite solder and the preparation method thereof, the melting point of the whole composite solder is stabilized to be 175-200 DEG C by adjusting the In content, so that the high-reliability medium-temperature composite solder is accurately matched with a backflow technology at the temperature of 180-210 DEG C, and the thermal requirements of different electronic devices are met; and after the nano metal powder and the nano graphene powder are added, the In-rich phase remelting rate during secondary backflow is effectively reduced, the interface bonding strength is improved, and the reliability is remarkably improved.

The application discloses a kind of composite solder ball, preparation method and stacked package structure, comprising: composite core, by continuous phase matrix and strengthening phase are constituted, the strengthening phase accounts for 15%~30% of the total volume of core, the compression modulus of the composite core is ≥3GPa and thermal expansion coefficient is ≤55ppm / ℃;Metal transition layer, is coated in the polymer core;Tin silver alloy outer layer covering the metal transition layer.Composite core is constituted by continuous phase polymer matrix and strengthening phase fiber network, realizes high-temperature pressure resistance and low thermal expansion characteristics by specific volume ratio and mass ratio, maintains solid rigid characteristics in welding high temperature interval, directly bears mechanical load, completely eliminates the risk of interlayer height collapse, metal transition layer forms and the mechanical interlocking combination interface of core, tin silver alloy outer layer provides weldability and electrical connection function, realizes that composite solder ball can play the role of support and also can play the role of welding dual-functional technology fusion.

The application belongs to the technical field of tin paste, and particularly relates to a semiconductor packaging tin paste and a preparation method thereof for reducing welding cavities, which is composed of the following materials: composite solder powder: nano heterojunction composite tin powder, with a mass ratio of 85%-92%; flux: temperature-sensitive microcapsule flux, with a mass ratio of 7%-15%; trace functional additives: rheological agent, antioxidant and thixotropic agent, with a mass ratio of 0.15%-0.7%. The Mott-Schottky effect is used to enhance the interface electron transfer capacity, the organic small molecules of the flux residue can be actively catalyzed and decomposed in the welding heating stage, and the gas escape is reduced. Meanwhile, the lattice matching property of the heterojunction can inhibit the abnormal growth of the IMC layer, and the cavity problem caused by the uneven interface reaction of the traditional tin powder is solved.

This invention belongs to the technical field of lead-free solder powder for electronic soldering. The invention discloses a graphene-coated copper-tin composite solder powder and its preparation method. The core phase is a CuSn binary alloy powder, with a Cu content of 0.5~1.0 wt% and the balance being Sn; the D50 particle size is 15~45 μm, approximately spherical, and the loose packing density is 4.8~5.2 g / cm³. 3，壳相：少层还原氧化石墨烯，连续致密包覆层厚度 The graphene coating is 0.8~3.0nm, with a coating amount of 0.03~0.22wt% (based on the total mass of the composite solder powder). The interface is that the core phase and the shell phase are covalently bridged by silane coupling agent, with a coating integrity rate of ≥95%. The graphene does not agglomerate or fall off, and it plays a stable role in the reflow soldering process. The wettability, solder joint strength, and thermal fatigue performance of the solder powder reach or exceed those of SAC305 silver-containing solder powder. The process conditions are mild, highly controllable, and have good repeatability, making it suitable for large-scale industrial production. Moreover, the preparation process is environmentally friendly and generates no harmful waste.

The invention discloses composite brazing filler metal with a reinforced foamy copper structure and a preparation method of the composite brazing filler metal. The composite brazing filler metal is prepared by taking foamy copper as a framework and filling pores of the framework with composite powder composed of silver powder and copper-titanium nanoparticles. The composite brazing filler metal comprises, by mass, 1%-5% of titanium, 18%-44% of copper and the balance silver powder and inevitable trace impurities. Weighing silver powder and copper-titanium nanoparticles, and uniformly mixing the silver powder and the copper-titanium nanoparticles to obtain composite powder; filling the composite powder into pores of the foamy copper, compacting the composite powder through vibration or pressing, and pressing to prepare a brazing filler metal preform; and performing low-temperature sintering on the brazing filler metal preform to obtain the composite brazing filler metal. The capillary flow of the liquid alloy in the brazing process is promoted through the porous structure of the foamy copper, the spreadability and the interface reaction efficiency of materials difficult to wet such as ceramic are optimized by combining the uniformly distributed copper-titanium nanoparticles and the silver powder, and the overall strength, plasticity and crack propagation resistance of the composite brazing filler metal are improved.

The invention relates to a solder and a preparation method and application thereof, the solder comprises the following main components by mass: 10%-30% of Si, 10%-45% of KxALFy (wherein x is 1-3 and y is 4-6), 0.5%-2% of a water-based adhesive, 40%-70% of a solvent, 0%-0.8% of Fe, 0%-0.5% of Mn, 0%-1% of Zn, and the balance of Al and inevitable impurities, and the mass ratio of Cu is 0-1%. The preparation method comprises the following steps: taking solid-phase components including 10-30 parts by mass of Si, 10-45 parts by mass of KxALFy, 0-0.8 part by mass of Fe, 0-0.5 part by mass of Mn, 0-1 part by mass of Zn and 0-1 part by mass of Cu, taking 0.5-2 parts by mass of a water-based adhesive, and mixing the solid-phase components, the water-based adhesive and 40-70 parts by mass of a solvent; and stirring. Welding machining between two or more parts without composite solder layers is achieved, and the machining cost is reduced.

The application relates to the technical field of semiconductor welding, and discloses a multilayer composite solder preform and a preparation method thereof. At least two high-melting-point metal strips are combined into an intermediate metal composite layer through multiple rolling, annealing and surface oxygen removal treatment, and then are combined with a solder strip to obtain a multilayer composite structure in which a first solder layer, at least two high-melting-point metal layers and a second solder layer are sequentially stacked. The high-melting-point metal layer can be two or three layers, and the material is selected from pure metals or alloys of Cu, Ni, Ag, Sb and the like; and the solder layer is pure Sn or Sn-based, pure In or In-based material. The problems of the existing three-layer structure solder, such as thermal expansion mismatch, poor thermal conductivity, low diffusion rate and poor base material adaptability, are solved, low-temperature welding (<300 DEG C) and high-temperature service (>400 DEG C) are realized, the thermal expansion coefficient is reduced by 30%, the thermal conductivity coefficient is increased by 300%, a single intermetallic compound layer is formed after welding, and the reliability of the welded joint is remarkably improved.

The utility model belongs to the technical field of welding devices, and discloses a high-frequency induction composite welding flux device which comprises an input piece and an output piece, and a welding piece is installed between the input piece and the output piece. The input part comprises a conveying part, two electric push rods are symmetrically and fixedly connected to the bottom of the conveying part in the moving direction of the material belt, two moving plates are symmetrically arranged above the conveying part, a plurality of guide rollers are rotationally connected to the opposite sides of the two moving plates, and moving rods are fixedly connected to the opposite sides of the two moving plates; a connecting plate is fixedly connected between the free end of the moving rod and the telescopic end of the electric push rod. The electric push rod drives the connecting plate and the moving rods to move, so that the moving rods drive the moving plates to move, the guide rollers on the two moving plates abut against the material belt, the material belt is centered, the material belt can be conveniently aligned with a welding piece, workers do not need frequent manual intervention, the welding difficulty of the device is improved, and the welding efficiency of the device is improved.

The invention provides a tin-based composite solder with CTE gradient transition and application of the tin-based composite solder in power module connection, the solder is a preform with an internal continuous gradient structure, firstly, in the directional solidification process, macroscopic component gradient is spontaneously formed through density-driven phase separation; subsequently, during welding application, the active Ti element is migrated to and reacts with the ceramic interface to generate a high-strength interface layer, and the gradient is further sharpened and strengthened. According to the welding flux, intrinsic CTE matching with a ceramic / copper heterogeneous material is achieved, interface thermal stress can be effectively dispersed, and the connection reliability is remarkably improved. In addition, an existing welding process does not need to be changed during application, and the method has excellent engineering applicability and commercial prospects and is suitable for high-reliability IGBT, SiC and other power modules.

The invention discloses a super-thick copper circuit board solder resist printing oil technology, and relates to the technical field of printed circuit board manufacturing. The process comprises the following steps: acquiring circuit distribution data of the ultra-thick copper circuit board, and dividing the surface of the ultra-thick copper circuit board into a circuit copper layer region and a non-circuit substrate region based on a partition priority strategy; first solder resist ink is jet-printed in a non-circuit area by adopting ink-jet printing equipment in a partitioned manner, and the stacking and the thickness of the ink are regulated and controlled through multi-stage partitioning and a jet printing mode, so that efficient covering of the side wall of a copper layer and high-leveling filling of a base material are realized; and performing staged pre-baking after jet printing, then printing second solder resist ink on the whole surface through silk-screen printing to form a composite solder resist structure, and finally curing the composite solder resist structure. According to the invention, the industrial problems that the super-thick copper PCB solder mask layer is difficult to cover the high side wall, the production efficiency is low and the quality consistency is poor are effectively solved. The coating property and the leveling property of the solder resist ink are improved, the process period is shortened, and the production efficiency is improved.

The invention relates to the technical field of tin-based composite solder preparation, in particular to a preparation method of photovoltaic solder strip alloy solder which comprises 2.8%-3.2% of silver, 0.45%-0.55% of copper, 0.03%-0.1% of nickel-coated nanometer aluminum oxide, 0.005%-0.02% of germanium and the balance tin. The preparation method comprises the following steps: melting a tin block, adding copper particles and silver particles, heating until the alloy is completely melted, cooling, adding Sn-Ge master alloy, slowly adding nickel-coated nano aluminum oxide powder into the melt in a nitrogen injection and ultrasonic coupling stirring manner, heating and refining, cooling and standing to obtain an alloy solder melt, and carrying out heat treatment on the alloy solder melt. The copper strip is prepared into a photovoltaic welding strip through a hot dipping method; through coordination of nickel-coated nano aluminum oxide and germanium, the initial shear strength of a welding spot of the welding flux is improved, the welding spot can keep a high strength retention rate under cold and hot circulation and long-term high-temperature environment service, and the problem that the shear performance of the welding spot is rapidly attenuated in a severe environment is solved.

The invention discloses a gradient alloy skeleton reinforced composite solder and a preparation method and application thereof. The gradient alloy skeleton reinforced composite solder is formed by compounding a component gradient alloy skeleton with a core-shell structure and a solder, wherein the component gradient alloy skeleton with the core-shell structure is filled with the solder; wherein the component gradient alloy framework with the core-shell structure comprises a metal framework and a Cu-Ni alloy coating layer. According to the gradient alloy skeleton reinforced composite solder, the high-melting-point metal skeleton on the inner layer serves as a slow reaction phase to keep a complete skeleton structure in the welding process, the good double-interpenetration reinforcing effect can be achieved, and the effect of supporting a weld joint can also be achieved; and the Cu-Ni alloy coating layer on the outer layer quickly reacts with the welding flux to form fine and dispersed metallurgical reaction particles, so that a good dispersion strengthening effect on a welding seam is achieved, and the reliability of a joint is improved through the combined action.