68 results about "Weld microstructure" patented technology

An electrosurgical medical device and method for creating thermal welds in engaged tissue. In one embodiment, at least one jaw of the instrument defines a tissue engagement plane carrying a conductive-resistive matrix of a conductively-doped non-conductive elastomer. The engagement surface portions thus can be described as a positive temperature coefficient material that has a unique selected decreased electrical conductance at each selected increased temperature thereof over a targeted treatment range. The conductive-resistive matrix can be engineered to bracket a targeted thermal treatment range, for example about 60° C. to 80° C., at which tissue welding can be accomplished. In one mode of operation, the engagement plane will automatically modulate and spatially localize ohmic heating within the engaged tissue from Rf energy application—across micron-scale portions of the engagement surface. In another mode of operation, a conductive-resistive matrix can induce a “wave” of Rf energy density to sweep across the tissue to thereby weld tissue.

The invention discloses a TIG (Tungsten Inert Gas) welding process for a narrow gap of a thick plate titanium alloy, which comprises six items adopted in the welding process, namely form of a welding gun, welding line spreading form, form of a welding groove, locking form before welding, selection of welding engineering parameters and selection of protective atmosphere in the welding process. The welding process solves the technical problem of the automatic TIG welding process for the narrow gap of the thick plate titanium alloy, realizes automatic TIG welding of the narrow gap of the thick plate titanium alloy, and has the characteristics of less time of weld beads, narrow heat affected zone and high welding efficiency. The residual stress and residual deformation of the welding joint are small, the weld structure is fine, and the welding performance is high.

The invention discloses a laser high-frequency alternating-current pulse tungsten inert gas (TIG) hybrid welding process. The process comprises the following steps of: constructing a laser high-frequency alternating-current pulse TIG hybrid welding system, and gathering an TIG arc and a semiconductor laser beam on the same welding position of a welded workpiece 8 in the same welding direction, to form a molten bath, wherein an inclined angle alpha of 10-40 degrees is formed between the TIG arc tungsten electrode tip end and a vertical direction, the semiconductor laser beam forms an included angle beta of 10-30 degrees with the vertical direction, the TIG arc tungsten electrode tip end keeps a vertical distance H of 2-4mm with the surface of the welded workpiece 8, and the TIG arc tungsten electrode tip end and the semiconductor laser beam keep a horizontal distance D of 2-5mm with an action point of the surface of the welded workpiece 8. The process disclosed by the invention can refine weld microstructure, remarkably reduce or eliminate pores in melting area and effectively improve mechanical performance and anti-stress corrosion performance of a high-strength aluminous alloy welding joint, and the process is quite practical.

The invention relates to a welding method of laser brazing of X 80 pipeline steel and belongs to the advanced manufacturing technology field. High energy laser source is utilized as unified preheating light source and welding light source to perform steps which comprises laser-bounce, transverse beam splitting, energy distribution and inward refocusing are performed on laser through a reflecting mirror, a spectroscope and a focusing mirror, the purpose of laser transverse beam energy distribution is achieved by adjusting the position of the spectroscope, distance between a front laser beam and a rear laser beam is adjusted by adjusting the size of a wedge angle of the spectroscope to form into the front laser beam and the rear laser beam, the front laser beam is served as a preheating light beam, the rear laser beam is served as a welding beam, and energy dispersion of the preheat light beam is performed through a concave lens when the preheating beam is utilized to preheat. The welding method of the laser brazing of the X 80 pipeline steel solves the problem that nonuniform weld microstructure caused by common welding is easy to cause electrochemical corrosion.

The invention provides a welding material for a butt fusion welding transition layer of a titanium-steel composite board and a preparation method of the welding material. The welding material comprises the components in percentage by weight as follows: 3.15%-3.35% of Mn, 18%-27% of Cr, 0.01%-0.015% of Cu, 0.35%-0.55% of Ti, 0.03%-0.04% of Co, 1.8%-2.0% of Nb, 0.2%-0.6% of Ta, smaller than or equal to 0.02% of C, smaller than or equal to 0.025% of Si, smaller than or equal to 0.002% of P, smaller than or equal to 0.75% of Fe and the balance of Ni, wherein the sum of the weight percentages of the components is 100%. The diameter of the welding material is small, weld microstructures of a titanium layer and a steel layer of the titanium-steel composite board can be effectively connected through manual TIG (tungsten inert gas) welding or MIG (metal inert gas) welding, butt fusion welding of the titanium-steel composite board is realized, and a welded joint has excellent strength and toughness; and the welding material is simple in preparation method, low in cost and suitable for batch production.

The invention discloses an active agent for the laser welding of ferrite stainless steel and a using method for the active agent. The method comprises the following steps of: respectively weighing and mixing 3 to 7 weight parts of ZrO2, 0.9 to 1.5 weight parts of CaO, 1 to 3 weight parts of MgO and 1 to 3 weight parts of carbonate, and fully grinding a mixture into the active agent; adding the obtained active agent into a solvent according to the weight ratio of 1:(0.3-0.8), and preparing paste; grinding the surface of a workpiece to be welded, and washing the workpiece by using absolute ethyl alcohol to remove oil stains from the surface; coating the paste on the surface of the pretreated workpiece to be welded; and after a coating is fully dried, performing the laser welding. Tests show that a ferrite stainless steel plate can be welded under lower power by the active agent under the conditions of the same welding parameters; the weld penetration can be remarkably improved; and a weld microstructure can be refined, and the number of isometric crystals of a weld zone can be increased. When the active agent is used for the laser welding, the using method is easy and convenient to operate and low in cost, and the welding efficiency can be greatly improved.

The invention discloses a method for improving a weld microstructure of Al/Cu friction stir welding in a follow-up manner. The method comprises the following steps: (1) adjusting the lowest working pressure, and adjusting the lowest pressing amounts of microstructure modification mechanisms; (2) adjusting the positions of the microstructure modification mechanisms by virtue of an adjustment-control mechanism, wherein two rolling wheels in a microstructure modification mechanism (II) with double rolling wheels correspond to the whole thermo-mechanical affected zone at an Al/Cu side as well as a part of a weld heat-affected zone and a part of a weld nugget zone; (3) starting up temperature control systems of the microstructure modification mechanisms, setting a modification temperature, setting a temperature T1 of the rolling wheels of a microstructure modification mechanism (I) to 290-315 DEG C, presetting a temperature T2 of the rolling wheels at an Al side of the microstructure modification mechanism (II) to 275-290 DEG C, setting a temperature T3 of the rolling wheels at a Cu side to 480-510 DEG C, heating the three rolling wheels to the modification temperature and then stopping heating; and (4) starting up a friction stir welding machine to start welding, enabling the microstructure modification mechanisms to start to work, and ensuring that the modification temperature set in the step (3) is achieved and stabilized until weld modification is ended during working by virtue of the temperature control systems of the microstructure modification mechanisms, wherein modification for the microstructure of the heat-affected zone can be realized after the end of the welding.

The invention relates to a short-circuit transient welding method and a system, which belong to the field of welding power supplies and welding automation equipment. According to the method, on the basis of a welding main current of a welding arcing stage, a high-frequency impulse is overlapped, so that the welding quality is improved by utilizing a high-frequency effect. At a short-circuit stage,a wire feed speed of a wire feeder is changed, so that wire feeding is slowed down; or a welding wire is withdrawn for assisting globular transfer. The invention additionally aims to provide the short-circuit transient welding system for implementing the welding method. The system adopts an alternate wire-feed method, meanwhile, a short-circuit state or an arcing state in a welding process can bedetected, and an appropriate welding current is output. In addition, at an arcing stage, a high-frequency impulse with the frequency being larger than 20kHZ can be overlapped. The researches show that by utilizing an electric arc with a high-frequency effect for welding, the welding stability and the electric arc stiffness can be greatly improved, and in addition, the high-frequency electric archas an effect on refining grains, so that weld microstructures and joint performances are favorably improved.

A quality control method for a high-frequency resistance welded pipe welding area includes the steps: firstly, heating a surface to be welded to reach the temperature T (DEG C)=1538-113wc by induction for 5-10s; secondly, arranging two inert gas sprayers of surfaces to be welded of two sides of a welding seam of a welded pipe respectively; thirdly, simultaneously spraying inert gas to the surfaces to be welded by the sprayers during welding until the welding seam is completely fused under the action of pressure to effectively reduce non-metallic inclusion of the welding seam; fourthly, performing local heat treatment for the welding seam by means of induction heating after welding, controlling the heating temperature to range from 920 DEG C to 940 DEG C and performing air cooling to obtain uniform weld microstructures; and fifthly, performing bulk heat treatment for the welding seam after local heat treatment, reducing internal stress of the welding area, stabilizing the microstructures to obtain a high-quality resistance welding joint, and reducing sensitivity of the welding seam to stress corrosion and groove corrosion. Gas flow is 5-10L/min, and the quality control method has the advantages of convenience in implementation and popularization, and remarkable effects.

The invention provides a 3D additive-manufacturing bilateral laser welding method for a T-shaped structure, relates to a double-laser-beam welding method, and aims to solve the problems that under the conditions of high welding speed and long weld beads, in a bilateral laser welding process of a T-shaped structure, the circumstance that welding wires are continuously and stably fed into a molten pool at constant speed and even, coherent and non-defective bilateral weld joints are obtained by one-time welding is difficult to ensure, and alloy of weld microstructures is difficult to regulate and control specifically and flexibly. The method comprises the following steps: 1, chemically cleaning the surface of a stringer; 2, designing of a sedimentary layer: designing the sedimentary layer in a region to be welded on the surface of the stringer, wherein the cross section of the sedimentary layer is square or rectangular; 3, vertically placing a laser cladding head at a position right above the region to be welded on the surface of the stringer, carrying out laser 3D additive-manufacturing on regions to be welded on two sides of the stringer to obtain the sedimentary layer in a mode of coaxially feeding laser beams and alloy powder; and 4, carrying out bilateral laser welding on the stringer and an envelope to obtain bilateral symmetric weld joints. The 3D additive-manufacturing bilateral laser welding method for the T-shaped structure is used for double-laser welding of the T-shaped structure.

The invention discloses a metal flux-cored wire for 25Cr2Ni4MoV steel and a preparing method. The metal flux-cored wire comprises a flux core and welding scale; the flux core is composed of componentsincluding, by mass percent, 1% to 4.0% of ferrosilicon powder, 6.0% to 15.0% of ferromanganese powder, 20.0% to 30.0% of nickel powder, 8% to 15% of chromium powder, 5% to 15% of FeMo powder, 1% to 5% of vanadium iron powder, 1% to 5% of copper powder, 1% to 2% of rare-earth powder and the balance iron. The sum of mass percents of the above components is 100%. The preparing method comprises the steps that raw material powder is matched according to the proportion, and is mixed and dried, the powder is added into a U-shaped groove formed through rolling of low-carbon steel strip, the powder issubject to grinding and closing, drawing, straightening and coiling into a disc, and seal packaging is carried out. The flux-cored wire is attractive in welding seam forming, the martensitic stainless steel weld microstructure can be obtained, the welding joint has the excellent mechanical property, and the preparing method is simple, suitable for an automatic welding machine and batched production.

The invention relates to a deep penetrating fillet welding process for hydraulic support structure piece mid-thickness plate welding. The process comprises the steps of cleaning a to-be-welded area, connecting a welding gun to a welding power supply, preparing welding shielding gas and a solid welding wire, and welding by using a welder. According to the process, the method is reasonable and feasible, weld metal is greatly saved under the same load bearing capacity, welding workload is reduced, the weld joint fusion is improved, the filling material is saved, the welding time is reduced, the weld joint strength is improved, the technical problems that an existing hydraulic support mostly adopts multi-layer and multi-pass welding of a mid-thickness plate, the welding number is excessive, the welding workload is increased, the welding defect probability is increased, the welding failure rate is increased, the welding heat for a weldment is increased, the weld microstructure is coarse, the strength and toughness are reduced, and the product quality and the enterprise production benefit are influenced are solved, and compared with the prior art, the process has good market prospect anddevelopment space.

A welding method and apparatus are provided for forming a weld joint between first and second elements of a workpiece. The method includes heating the first and second elements to form an interface of material in a plasticized or melted state interface between the elements. The interface material is then allowed to cool to a plasticized state if previously in a melted state. The interface material, while in the plasticized state, is then mixed, for example, using a grinding/extruding process, to remove any dendritic-type weld microstructures introduced into the interface material during the heating process.

The invention relates to an active agent used for aluminum alloy MIG (metal-insert gas) welding and an application method of the active agent. The active agent is prepared by powder particles including, by weight, 40%-55% of B203, 25%-40% of NaF, 10%-15% of Si02 and 0% to 5% of MgC03 with the particle size ranging from 60 to 80 micrometers and the fineness ranging from 95% to 99%. The application method includes: performing burdening on the active agent according to the weight, blending a mixture with an organic solution after the mixture is well blended, and stirring the same into paste; carefully polishing base metal with a stainless steel wire brush till the polished metal is exposed and using acetone to scrub the surface of a work piece to remove surface oil stains; covering the prepared paste on the surface of the welding work piece till metal luster is covered; performing normal MIG welding after the organic solution is volatilized. By the application of the active agent, welding line grains can be refined, weld microstructure can be improved, weld penetration can be increased, property of welded joint can be improved, and operation easiness can be achieved.

The invention provides a forming method of an aeroengine hollow guide vane. The method includes: forging a vane body blank and an exhaust edge insert blank respectively, machining fitting faces of the vane body blank and fitting faces of the exhaust edge insert blank, and connecting the vane body blank and the exhaust edge insert blank for formation by means of friction stir welding. Through the application of the method, the problem that the hollow structure of the large-sized hollow guide vane cannot be formed by the existing forging technologies is solved; compared to the background techniques, the method is significantly advanced. Through the application of the novel technique double-side symmetric friction stir welding, first pass yield during the forming process of hollow vanes is increased greatly, production efficiency is improved, and production cost is reduced. Experiments show that after the application of the method, weld microstructure is compact with no obvious defects such as pores and inclusion, the production process is easy to mechanize, first weld yield is increased from 25.54% to 92.25%, and weld strength is increased by more than 50%.

The invention relates to the technical field of pipe induction heating equipment annealing technologies, especially a pipe induction heating equipment inductor. The inductor comprises a first inductor winding, a second inductor winding and a third inductor winding, and is characterized in that: the first inductor winding, the second inductor winding and the third inductor winding are wound on the outer surface of a workpiece along the workpiece operation direction in order, wherein the first inductor winding, the second inductor winding and the third inductor winding have different and increasing turns of induction heating coils. The pipe induction heating equipment inductor provided by the invention adopts three inductor windings with different turns of induction heating coils to eliminate the residual stress of products after solution annealing, improves multiple indicators of the weld microstructure, grain structure and extensibility, greatly upgrades the product quality, and obviously enhances the heat treatment work efficiency and product quality to meet market demands.

The invention provides a laser wire feeding welding method for aluminum-silicon-coated hot formed steel. A well formed aluminum-silicon-coated hot formed steel laser wire feeding lap weld can be obtained by adopting a high-strength steel welding wire to perform laser wire feeding welding on the aluminum-silicon-coated hot formed steel. For the laser wire feeding welding method provided by the invention, by selecting a high-strength steel welding wire as a proper filling material, a laser wire feeding process is controlled to dilute an aluminum coating dissolved in the weld through the fillingmaterial, such that a weld microstructure is controlled, a high-quality lap joint welding head is obtained, and meanwhile, the laser wire feeding welding method is also suitable for aluminized siliconhot formed steel welding for an automobile. Compared with a traditional laser lap joint method, by adopting the laser wire feeding welding method provided by the invention, without removing an aluminum-silicon coating on the surface of the hot formed steel, the lap welding process flow is simplified, and the production efficiency is improved; and meanwhile, due to the fact that the welding wire is dissolved, the problem of surface collapse easily caused by self-welding is solved, and the weld is full, such that the strength of the lap joint welding head is improved, that is the mechanical property of the lap joint is improved.

The invention relates to welding equipment, in particular to a welding device for an internally-clad stainless steel tube of a clad steel plate. The welding device comprises an MIG welding power source, an automatic wire feeder and an MIG welding gun. The MIG welding gun is mounted on a three-dimensional gun rack through a gun clamp, and the three-dimensional gun rack is mounted on a welding gun support. Sizing rolls are mounted below the MIG welding gun, and a welding fixture is mounted between the sizing rolls. One end of the welding fixture is mounted on a welding support, a steel tube to be welded enters the welding fixture from a straight-seam tube manufacturing production line and enters the position between the sizing rolls, and the steel tube is welded by the MIG welding gun. The welding device for the inner composite stainless steel tube of the clad steel plate is in butt joint with a common straight-seam tube manufacturing production line or a spiral tube manufacturing production line, open arc automatic welding is conducted from the outer surface of the steel tube, one-time welding is achieved, and the welding quality and the production efficiency are improved. Weld joint single-face welding and double-face forming of dissimilar metal welding are achieved. The quality of a welding joint is improved, particularly, the weld microstructure of a stainless steel composite layer face achieves two-phase organization, and therefore the corrosion resistance is better than that of a base material.

The invention discloses a laser welding method for a high-grade silicon steel plate. The purposes are to improve the quality of a welding seam before a normalizing process and the quality of the welding seam after the normalizing process, avoid welding defects and cracks, reduce the strip breakage rate of the silicon steel plate in the continuous production process and improve the production efficiency. The Si content of the silicon steel plate is 1.75-3.45% in a mass ratio, and the thickness is 1.85-2.90 mm. The method is characterized in that the laser welding power and the heating and annealing power of a post-heating and annealing process are adjusted according to the total Si content (Si1 + Si2) and the total thickness (h1 + h2) of a front roll and a rear roll of high-grade silicon steel plates, and single-side splicing welding is achieved. According to the method, specific laser welding process parameters are provided according to the difference of the total Si content and the total thickness of the steel. By adopting the method, the weld microstructure can be improved, the hardness difference between a weld area and a base metal area is reduced, the welding stress is reduced, and the weld quality is improved; and in addition, the method further has the advantage of low welding energy consumption.