64results about How to "High solder joint strength" patented technology

The invention discloses cleaning-free solid-state scaling powder for aluminum low-temperature soldering and a preparing method. According to the weight percentage, the cleaning-free solid-state scaling powder comprises raw materials of 6.5%-18% of metal film-forming agents, 5%-18% of organic carriers, 0.1%-1.8% of corrosion inhibition agents and the allowance of film removing active agents. The film removing active agents are composite salt of organic amine and acid. The cleaning-free solid-state scaling powder is suitable for lead-free solder wires with solid-state scaling powder contained in a core, and the powder can be used for automatic welding, manual soldering iron welding or flame spraying welding. The core-contained solder wires prepared with the scaling powder have the advantages that tinning speed is high, splashing is low, irritating smoke is avoided, post-welding residues do not have corrosiveness, a welding point has great electrochemical corrosion resistance, a contact service time is long, the wires are suitable for assembling welding of an aluminum coated layer circuit board and an aluminum soldering pin electronic element and brazing of an aluminum electric cable wire, an aluminum radiator and aluminum heat exchanging equipment.

The invention belongs to the technical field of material engineering and relates to a connection technique for metals, in particular to a welding and adhesive jointing combined connection technique for metals, which comprises: applying adhesive for structural curing on the joint surfaces of materials to be welded; jointing the materials; and welding. The technique is characterized in that: an adhesive layer which is 0.02 to 1 millimeter thick is uniformly applied between the jointing surfaces of the materials to be connected; after joining, through holes with an aperture of 3 to 10 millimeters are formed on a jointed part at 15 to 50 millimeter intervals along a joint, and performing double-sided filler wire spot welding at the holed part with an arc weld; and heating the jointed parts between which a glue layer is applied to 50 to 500 DEG C before welding and after welding, and keeping the temperature for 10 to 180 minutes. The method can increase the strengths of the welded spots, avoid surface collapse caused by other adhesive bonding, improve the bearing load, fatigue strength and shearing performance of difficult-to-weld welded structure made of one kind of metal and different kinds of metals, and meet actual engineering needs.

The invention relates to a laminated method for producing metal element, which comprises: building model, dispersing the model, processing layer; based on the data document, using material transmitter to transmit the laminated material; using ultra-sonic welding technique to weld nearby two layers; based on the laminated information, removing the layer surface of welded material, to realize the horizontal and vertical motions; processing the next layer. The inventive ultra-sonic welding has less power consumption, small deformation of welding element, and high strength of welding point. Therefore, the product has high accuracy and lower cost.

A system and method is disclosed for improving solder joint reliability in an integrated circuit package. Each terminal of a quad, flat, non-leaded integrated circuit package is formed having portions that define a solder slot in the bottom surface of the terminal. An external surface of the die pad of the integrated circuit package is also formed having portions that define a plurality of solder slots on the periphery of the die pad. When solder is applied to the die pad and to the terminals, the solder that fills the solder slots increases the solder joint reliability of the integrated circuit package.

The invention relates to high-temperature lead-free solder paste and a preparation method. The high-temperature lead-free solder paste comprises lead-free electronic grade tin alloy powder and flux. Diethylene glycol monobutyl ether, diethylene glycol octyl ether and hydroxyl-terminated polybutadiene are added into a temperature control emulsifying machine and are heated and mixed, hydrogenated castor oil, polymerized rosin CLEARON105# and hydrogenated rosin are added into the temperature control emulsifying machine and are mixed to obtain primary mixed liquor, the primary mixed liquor is cooled, 2,3-dibromo 1,4-butylene glycol, sebacic acid and phenyl-butanedioic acid are added into the primary mixed liquor and then are mixed to obtain secondary mixed liquor, the secondary mixed liquor is cooled, polyamide wax is added into the secondary mixed liquor and then is mixed to obtain tertiary mixed liquor, the tertiary mixed liquor is cooled, fluorocarbon surfactant and triethanolamine areadded into the tertiary mixed liquor and then are mixed and vacuumized until the temperature returns to room temperature, the lead-free electronic grade tin alloy powder Sn95Sb5 is added into the prepared flux after standing at the temperature of 22-25 DEG C, and the lead-free electronic grade tin alloy powder and the flux are mixed for 15-20 minutes to obtain the high-temperature lead-free solder paste. The high-temperature lead-free solder paste has the advantages of fine solderability and wettability, high solder joint strength, high reliability and solderability in air and nitrogen protection.

The invention belongs to a metal material and specifically relates to a beryllium-containing low-silver cadmium-free silver solder. The beryllium-containing low-silver cadmium-free silver solder is characterized in that the ingredient proportion by mass percent is as follows: 12%-16% of Ag, 39%-41% of Cu, 1%-8% of In, 0.5%-4% of Ga, 0.0001%-0.05% of Be and the balance of Zn, wherein the ratio of In to Ga is equal to 2:1. The beryllium-containing low-silver cadmium-free silver solder which is obtained by adopting the ingredient proportion has the characteristics of good mobility, excellent wettability, high welding spot strength, and the like, also has a melting temperature range approaching to the melting temperature range of a BAg20CuZnCd solder, and is especially suitable for the soldering of some products in the household appliance industry and hardware industry. The problems of workpiece oxidation, reducing of the soldered joint strength, and the like, caused by ultrahigh soldering temperature, are avoided.

The invention is concerned with aluminum alloy resistance spot welding method with filled titanium powder to melody the intension of melting core, belonging to aluminum alloy resistance spot welding technology. Dip the aluminum alloy plate into the NaOH liquid and clear with water and dip the plate into HNO3 liquid and clear with water and airing. Spread filled titanium powder at the welding spot of the two disposed aluminum alloy plate and carry the spot welding to the aluminum alloy plate with copper electrode with certain current, welding time and welding pressure. The method adds titanium powder in the core forming process of the resistance spot welding to form tiny compound spot of titanium powder among the metals and to restrain the restore and recrystallization of aluminum alloy. It refines the structure of melting core of aluminum alloy by enhancing the welding intension to over 2500 N.

The invention relates to a low-inductance power capacitor which comprises a cover plate assembly, a shell and a capacitor core set fixed into the shell. The capacitor core set is formed by overlapping a plurality of capacitance cores in a layering mode. A positive electrode leading copper strip and a negative electrode leading copper strip are mutually overlapped and arranged on the two sides of the non-metal-spraying face of the capacitor core set. Insulating layers are arranged between overlapped parts of the connecting parts of the positive electrode leading copper strip and the negative electrode leading copper strip and a terminal. The metal spraying faces of the two ends of each capacitor core are electrically connected to auxiliary leading copper strips respectively in a welding mode, wherein the auxiliary leading copper strips are transversely arranged. The two ends of each auxiliary leading copper strip of each end of the capacitor core set are fixed to the positive electrode or negative electrode leading copper strip through welding. The double leading copper strips are arranged on the two sides of the capacitor core set, the path for leading currents to the copper strips is the shortest, the current density is reduced, the self-inductance of the capacitor can be reduced obviously, and the safety performance of equipment like a current transformer can be improved.

The invention discloses a chip pin correction tooling. Since a guiding hole array composed of the guiding holes corresponds to a lead column array composed of lead columns, the guiding holes are onlyslightly larger than the diameter of the lead columns, and the texture of the lead columns is soft, the lead columns can be slowly pressed into the guiding holes of the calibration tooling to adjust the spacing among the lead columns and the morphology of the lead columns, so as to make the spacing among the lead columns and the topography of the lead columns meet preset standards; therefore, accurate positioning between chip pins and a PCB surface bonding pad can be realized, the combination degree of a solder and the pins is improved, the solder joint strength is improved, and the solderingreliability is improved. The invention also provides a chip installation method. The spacing among the lead columns and the topography of the lead columns can be corrected through the correction tooling; therefore, the accurate positioning between the chip pins and the PCB surface bonding pad can be realized when soldering the chip to the surface of the PCB, the combination degree of the solder and the pins is improved, the solder joint strength is improved, and the soldering reliability is improved.

The invention belongs to metal materials, in particular to a cobalt-containing low-silver cadmium-free silver solder. The cobalt-containing low-silver cadmium-free silver solder is characterized by comprising the following components in percentage by mass: 12 to 16 percent of Ag, 39 to 41 percent of Cu, 1 to 8 percent of In, 0.5 to 4 percent of Ga, 0.01 to 1.2 percent of Co, and the balance of Zn, wherein In:Ga=2:1. The cobalt-containing low-silver cadmium-free silver solder obtained by the component proportion has the characteristics of high fluidity, high wettability, high welding spot strength and the like, has the melting temperature range close to that of the Bag20CuZnCd solder, and is particularly suitable for soldering some products in household electrical appliance industry and hardware product industry; the problems of workpiece oxidization, reduction of soldering joint strength and the like caused by over-high soldering temperature are avoided.

The invention provides a pressure welding process for lowering welding spatter. The pressure welding process comprises spot welding and convex welding, wherein the spot welding or convex welding parameters set millisecond as a unit; when pressure welding adopts spot welding, the welding time for each pulse is 6 ms-20 ms, the cooling time is 3 ms-20 ms, and the pulse quantity is 10n-40n; when the pressure welding adopts convex welding, the welding time for each pulse is 6 ms-20ms, the cooling time is 3 ms-20ms, and the pulse quantity is 4n-10n. The pressure welding process is full in welding nugget, increased in welding spot strength, and eliminates welding spatter. A follow-up polishing process is not needed, the welding quality is improved, the surface appearance of the welding part is improved, and ineffective labor is eliminated. The pressure welding process is especially suitable for a high-strength plate or a thermally-formed high-strength steel plate, relatively good in using effect and wide in scope of application.

The invention discloses a method for inhibiting generation of internal defects of an aluminum alloy resistance spot welding nugget, and belongs to the technical field of resistance spot welding. A welding current is divided into an electrifying heating stage, a cooling stage and a pressure maintaining stage, wherein in the electrifying heating stage, the current amplitude of the welding current is15KA-60KA, and the electrifying time is 50ms-200ms; and in the cooling stage, the current is 0-15KA, and the cooling time is 2ms-40ms. According to the welding method, due to the existence of the cooling stage, welding heat input is stable, and internal stress of a welding spot is reduced, so that the generation of the defects such as cracks and air holes in the nugget is inhibited, and the effect of improving the strength of the welding spot is achieved.

The invention discloses a resistance spot welding electrode cap. A groove is formed in the center of a welding contact surface of the electrode cap; in the welding process, the contact area between the electrode cap and a to-be-welded metal workpiece is reduced due to the existence of the groove; in the initial stage, overall produced heat is concentrated to outer rings of welding spots, so that the heat dissipation speed is low, and formation of molten cores from outside to insideis facilitated; and due to the existence of the groove, the metal workpiece expands towards the sunk part of the center of an electrode, the molten cores of the welding spots areincreased, and splashing and deforming are reduced. Compared with a traditional electrode cap, the welding current needed for forming the welding spots inthe same size by the electrode capis lower, and the electric power cost is reduced; and when the same current is used, the strength and the stability of the obtained welding spots are higher, and the welding defects are fewer.

The invention belongs to the technical field of solder, and particularly relates to a lead-free low-temperature solder. The solder comprises, by mass, 0.001-58.0% of bismuth, 0.001-1.0% of silver, 0.001-2.0% antimony, 0.001-0.1% of indium, 0.001-0.15% of phosphorus, 0.001-0.08% of germanium, 0.001-0.015% of beryllium, 0.001-0.015% of cerium and the balance tin. Compared with the prior art, when welding is carried out at the temperature of 139DEG C to 200DEG C, little oxidation slag is generated, the surface of a tin furnace can be kept bright basically without oxidation at the temperature, thesolder can not be oxidized within 50 seconds at 200-260 DEG C, so that the welding efficiency is greatly improved, and the damage to electronic components of a PCBA board is reduced; the low-temperature solder is good in oxidation resistance; and in the welding process, compared with a common Sn-Ag-Cu system, the solder has fewer welding defects, the surfaces of welding spots are very light-bright, the welding spots are full, continuous welding does not occur, so that the welding quality is effectively improved, and the solder and the method are environment-friendly and safe.

The invention discloses a splashing-free resistance spot-welding method of galvanized steel plates for a car. The method is characterized by comprising the following steps that 1, a Cu middle layer isarranged between to-be-welded portions of the two galvanized steel plates to be welded, and the thickness of the Cu middle layer is 0.02-0.20 mm; 2, spot welding pre-pressing is carried out on the two galvanized steel plates to be welded, and pre-pressing time is 1000-2000 ms; and 3, spot welding is carried out on the to-be-welded portions of the two galvanized steel plates to be welded. According to the method, generation of splashing in the welding process can be prevented, strength of welding spots is improved, and the problem of spot welding of the galvanized steel plates is solved.

The invention belongs to the field of metal materials, in particular to a high-spreadability tin-antimony-rare earth lead-free solder alloy and a preparation method thereof. The alloy is prepared from the following raw materials in percentage by weight: 7.0 to 9.0 percent of Sb, 0.01 to 0.03 percent of In, 1 to 3 percent of Bi, 0.01 to 0.03 percent of Cd, 0.01 to 0.03 percent of Sm, 0.01 to 0.03 percent of Nd and the balance of Sn. The preparation method comprises the following steps of: smelting the raw materials in the ratio in a vacuum induction furnace to obtain a master alloy; remelting in a remelting tubular crucible, wherein the remelting tubular crucible is arranged above a rim of a rotating wheel of a quick quenching furnace, and molten alloy is sprayed through holes with the diameter of 1mm at the bottom of the crucible under the action of argon and forms an alloy strip on the rim of the rotating wheel; properly crushing the alloy strip; and grinding in a ball mill, taking out, and sieving. The alloy has high strength and high spreadability.

The invention provides a method for improving conductive solder welding electronic packaging strength based on electrowetting principle, which includes the steps of: making a substrate base plate which is provided with a solder joint structure and a conductive electrode; carrying out electrowetting treatment, heating the substrate base plate to a temperature above the melting point of the solder to enable the solder to be in molten state; and applying voltage to the conductive electrode of the substrate base plate to reduce the surface tension of the solder by making use of the electrowetting effect, so as to increase the contact area of the solder joint structure and the substrate base plate. Compared with the prior art, the method provided by the invention has the advantages that electrowetting principle is adopted in the technical scheme, so the contact area of the solder joint structure can be increased and correspondingly the welding strength of the solder joint structure can be improved and the reliability of a semiconductor device can be improved.

The invention is concerned with aluminum alloy resistance spot welding method with filled chrome powder to melody the intension of melting core, belonging to aluminum alloy resistance spot welding technology. Dip the aluminum alloy plate into the NaOH liquid and clear with water and dip the plate into HNO3 liquid and clear with water and airing. Spread filled chrome powder at the welding spot of the two disposed aluminum alloy plate and carry the spot welding to the aluminum alloy plate with copper electrode with certain current, welding time and welding pressure. The method adds chrome powder in the core forming process of the resistance spot welding to form tiny compound spot of chrome powder among the metals and to restrain the restore and recrystallization of aluminum alloy. It refines the structure of melting core of aluminum alloy by enhancing the welding intension to over 2500 N.

The invention discloses an inserted inlaid butt welding structure of a ceramic metal halide electrode. An electrode main pole is a tungsten electrode main pole, molybdenum electrode main pole, alloy tungsten electrode main pole or alloy molybdenum electrode main pole; a lead-out pole is a niobium lead-out pole or niobium/zirconium alloy lead-out pole; one end of the electrode main pole is inserted into the end surface of one end of the lead-out pole; and the outer wall of the inserted end of the electrode main pole and the end surface of the lead-out pole are welded. The inserted inlaid structure disclosed by the invention is reasonable; the electrode main pole and the grain boundary of the niobium lead-out pole are fully melted; no seam or gap exists between a molybdenum sleeve and the niobium/zirconium pole; and the strength of the welding spot is high, and two-segment breakage is prevented in the case of 90-degree bending. Due to the close and perfect connection between the tungsten pole and niobium pole, the resistance consistence of the product is assured to be very high; and the quality hidden danger of air leakage in sealed connection of an electrode and a ceramic tube caused by the problems of rough welding spots, hollow welding, insufficient welding and the like of the current laser welding is effectively avoided.