5675 results about "Shielding gas" patented technology

A method of fabricating a long carbon nanotube yarn includes the following steps: (1) providing a flat and smooth substrate; (2) depositing a catalyst on the substrate; (3) positioning the substrate with the catalyst in a furnace; (4) heating the furnace to a predetermined temperature; (5) supplying a mixture of carbon containing gas and protecting gas into the furnace; (6) controlling a difference between the local temperature of the catalyst and the furnace temperature to be at least 50° C.; (7) controlling the partial pressure of the carbon containing gas to be less than 0.2; (8) growing a number of carbon nanotubes on the substrate such that a carbon nanotube array is formed on the substrate; and (9) drawing out a bundle of carbon nanotubes from the carbon nanotube array such that a carbon nanotube yarn is formed.

Information pertaining to characteristics of consumables such as metal welding electrode wire and shielding gas and which characteristics are useful in connection with adjusting welding parameters in an arc welding process and/or selecting between operating modes in a welding system are encoded on welding wire and/or on other memory components such as bar code labels and tags, RFID cards and tags, IC cards, and Touch Memory buttons, and the memory device is scanned prior to and/or at the point of use of the welding wire or shielding gas for enabling tracking of product distribution, manual and/or automatic selection of an operating mode for the welding system, manual and/or automatic adjustment of welding parameters in a given operating mode, consumables inventory, and the like.

The present invention relates to arc welding torch and a method of extracting fume gas from a welding site. The torch comprises a metal electrode and at least one shield gas port adapted to direct a shield gas curtain around the metal electrode and a welding site. At least one shroud gas port is spaced radially outward from the shield gas port and adapted to impart to an exiting shroud gas a radially outward component of velocity. Fume gas is preferably extracted from a position radially intermediate the shield gas curtain and the shroud gas curtain.

A method and apparatus for controlling a gas supply to a plasma arc torch uses a proportional control solenoid valve positioned adjacent the torch to manipulate the gas flow to the torch, thereby extending electrode life during arc transfer and shutdown. Swirl ring design can be simplified and gas supply and distribution systems become less complicated. The invention also allows manipulation of shield gas flow to reduce divot formation when making interior cuts. The system can be controlled with a digital signal processor utilizing a feedback loop from a sensor.

A method for forming a carbon nanotube array on a metal substrate includes the following steps: providing a metal substrate (11); depositing a silicon layer (21) on a surface of the metal substrate; depositing a catalyst layer (31) on the silicon layer; annealing the treated substrate; heating the treated substrate up to a predetermined temperature in flowing protective gas; introducing a carbon source gas for 5-30 minutes; and thus forming a carbon nanotube array (51) extending from the treated substrate. Generally, any metallic material can be used as the metal substrate. Various carbon nanotube arrays formed using various metal substrates can be incorporated into a wide variety of high power electronic device applications such as field emission devices (FEDs), electron guns, and so on. Carbon nanotubes formed using any of a variety of metal substrates are well aligned, and uniformly extend in a direction substantially perpendicular to the metal substrate.

Welding systems including welding torch assemblies are provided. The welding torch assembly may include a welding torch adapted to be utilized in a welding operation to establish a welding arc between the welding torch and a workpiece. Shielding gas may be supplied to the welding torch for establishment of a gas shielding area around a weld pool. The welding torch assembly may also include a temperature sensing system having a non-contact temperature sensor coupled to the welding torch and adapted to sense a temperature of the workpiece at a location outside of the molten weld pool.

The invention relates to a tin-base leadless solder without silver, and relative production. Wherein, it comprises Bi at 7.5-60% (without 7.5%), Cu at 0.1-3.0%, and the left is tin; and it also can contain Zn, Ni, P, Ge, Ga, In, Al, La, Ce, Sb, Cr, Fe, Mn, or Co while the total amount of micro alloy element is not higher than 1.0%. And the production comprises that in protective gas or vacuum, smelting middle alloy Sn-Cu10; then smelting into leadless solder alloy ingot which can be used as solder directly or be made into bar band, wire plate or powder. The inventive solder has low cost while its fusion point can be controlled between 140 and 230Deg. C. And it has strong anti-oxidization and anti-corrosion properties.

Corrosion resistant non-polar polymer coatings and methods for applying the coatings to substrates are described, wherein a source of non-polar polymer powder is deposited as a coating onto the surface of a substrate by high temperature thermal spray. The non-polar character of the powder and any additives thereto is substantially preserved during the high temperature thermal spray process by the use, at one or more locations along the thermal spray route, of at least one non-oxidizing shielding gas, at least one reducing gas, or a combination of the two types of gases to displace or react with ambient oxygen. High velocity impact force (HVIF) spraying techniques are preferred. Similarly processes and materials for low permeability and non-corrosive HVIF coatings for steel fuel tanks are disclosed.

The invention discloses a high-yield preparing method for inorganic halogen perovskite fluorescent quantum dots at the room temperature. The fluorescent quantum dots are CsPbX3, wherein X is equal to AxB1-x and is larger than or equal to 0 and smaller than or equal to 1, and A and B are any one of Cl, Br and I. The method comprises the following steps that firstly, lead halide and cesium halide are dissolved into dimethyl formamide, surfactant oleylamine and oleic acid are added, the mixture is stirred until complete dissolution, and a precursor solution is obtained; secondly, the precursor solution is dripped into a poor solvent at the speed of 0.08-0.13 mL/s and stirred evenly at the uniform speed, and the inorganic halogen perovskite fluorescent quantum dots CsPbX3 are obtained. The preparing method is implemented at the room temperature, protection gas is not needed, equipment is simple, mass production can be achieved, and full visible light band shining can be achieved by selecting halogen and adjusting the proportion of halogen. The full width at half maximum of the inorganic halogen perovskite fluorescent quantum dots prepared through the preparing method ranges from 16 nm to 39 nm, the fluorescence quantum efficiency is close to 90%, and the inorganic halogen perovskite fluorescent quantum dots can be stably stored for more than three months, and can be used in the field of solar cells, lasers, light detectors, light-emitting diodes and the like.

A method for forming a carbon nanotube array includes the following steps: providing a smooth substrate (11); depositing a metal catalyst layer (21) on a surface of the substrate; heating the treated substrate to a predetermined temperature in flowing protective gas; and introducing a mixture of carbon source gas and protective gas for 5-30 minutes, thus forming a carbon nanotube array (61) extending from the substrate. When the mixture of carbon source gas and protective gas is introduced, a temperature differential greater than 50° C. between the catalyst and its surrounding environment is created by adjusting a flow rate of the carbon source gas. Further, a partial pressure of the carbon source gas is maintained lower than 20%, by adjusting a ratio of the flow rates of the carbon source gas and the protective gas. The carbon nanotubes formed in the carbon nanotube array are well bundled.

The invention discloses a method for performing microwave pyrolysis on garbage. The method comprises the following steps of: 1) pretreating the garbage to obtain structured garbage which is suitable for microwave pyrolysis; 2) performing microwave pyrolysis on the garbage, namely introducing pyrolysis gas out of a pyrolysis gas outlet of a microwave pyrolysis device, continuously outputting pyrolysis solid products from a pyrolysis solid residue discharge port on the microwave pyrolysis device, sealing the rest parts of the microwave pyrolysis device except a garbage inlet, the pyrolysis solid residue discharge port and a pyrolysis gas outlet to prevent the pyrolysis gas from being leaked and preventing external air from entering the microwave pyrolysis device to ensure that the pyrolysis gas is used as protective gas for pyrolysis reaction; and 3) recovering pyrolysis products, namely treating according to the pyrolysis products. The method has the characteristics of rapidness and high efficiency, low energy consumption, low cost, high resource utilization rate, simplicity in operation, high garbage volume reduction rate, capacity of obviously reducing damage of garbage to environment and the like; and by the method, innocent treatment of the garbage can be realized really.

The invention relates to an intensive anodic oxidation process to prepare porous anodic alumina film. An aluminum sheet is as an anode; a platinum sheet as a cathode; argon as shielded gas; mixed solution of perchloric acid with absolute alcohol as electrochemical polishing compound for the aluminum sheet; mixed solution of oxalic acid, absolute alcohol and deionized water as electrolyte; and mixed solution of phosphoric acid, chromic acid and deionized water as alumina film corrodent. Through aluminum sheet annealing, purging, electrochemical polishing, mild anodic oxidation, corrosion on aluminum sheet oxide film, intensive anodic oxidation and stripping oxide film, and finally, pale yellow, high purity and ordered porous-structured nanometer-leveled alumina film is achieved; The alumina film pore is in circular shape sized in 30 to 35nm, pore distance in 80 to100nm and pore depth in 162.4 micrometers; growth rate of the alumina film is 54 micrometers/h, which is 27 times higher than 2 micrometers/h of growth rate of anodic oxidation aluminum film prepared through mild anodic oxidation process.

The invention discloses a method for preparing graphene from lignin, which comprises the following steps: putting a porcelain sample boat filled with lignin and a catalyst into a hinge pipe furnace, introducing shielding gas at uniform speed while heating the sample in the furnace from room temperature to the target temperature at a constant heating speed, and keeping at the target temperature; and after the sample is cooled to room temperature, taking out the sample, washing with deionized water, carrying out vacuum filtration, and drying at low temperature to obtain the graphene. The preparation technique is simple and convenient; and the obtained graphene has the advantages of high quality and considerable yield.

The invention relates to a preparation method for a silicon carbide ceramic tube or rod. An extrusion moulding method is adopted to form a blank body; a normal pressure sintering method is adopted for sintering; and submicron level silicon carbide powder and additives are taken as main raw materials. The preparation method comprises the following steps: 1) carrying out ball milling on the main raw materials by a dry method, adding water, a dispersant, a plasticizer, a lubricant and a liquid state binder, and then carrying out ball milling by a wet method; 2) adopting a spray granulation process to granulate silicon carbide slurry; 3) extruding the blank body by a one-shot direct extrusion moulding method after vacuum pug, corrosion, and vacuum pug; 4) drying the molded blank body by a stage drying mechanism; and 5) placing the blank body of the silicon carbide ceramic tube or rod in a vacuum furnace and carrying out sintering for two times by taking argon gas as protective gas. The high temperature resisting strength and the corrosion resistance of the silicon carbide ceramic tube or rod prepared by the method are both better than those of a reactive sintered product. Compared with a hot press sintering method, the method has lower limit on the product shape and size, and lower cost. The method is suitable for the industrialized production.

The invention discloses a method for preparing a bimetal composite plate by stirring friction braze welding. The method comprises that: a plate with small hardness is used as a covering layer metal plate; a plate with high hardness is used as a base layer metal plate; the covering layer metal plate and the base layer metal plate are horizontally fixed on a working platform surface in a lap joint mode; solders which can generate eutectic reaction with one of the upper/base layer metal plates are preset between the upper/base layer metal plates; a non-needle type cylinder friction device is arranged over the covering layer metal plate; the non-needle type cylindrical friction device is made to rotate and be pressed to be closely contacted with the surface layer of the covering layer metal plate, but not penetrate the covering layer metal plate, and the non-needle type cylindrical friction device rotates in the original position or moves forward along the surface of the covering layer metal plate while rotating; by utilizing frictional heat to melt the solders, the upper/base layer metal plates are both quickly melted in the solders, thereby achieving excellent interface combination; and the excessive solders are squeezed out, and a thin and dense soldering seam is formed, so that the bimetal composite plate is prepared. Compared with the braze welding in a furnace, the method has the advantages of high efficiency, energy conservation, pressure lead-in, unnecessary soldering flux and gas protection and short holding time at a high temperature.

Improved methods for stripping photoresist and removing ion implant related residues from a work piece surface are provided. According to various embodiments, plasma is generated using elemental hydrogen, a fluorine-containing gas and a protectant gas. The plasma-activated gases reacts with the high-dose implant resist, removing both the crust and bulk resist layers, while simultaneously protecting exposed portions of the work piece surface. The work piece surface is substantially residue free with low silicon loss.

The apparatus for reduced-pressure refining of a glass melt includes a refining bank formed so that a reduced pressure is generated by a glass flow in it. The refining bank has a component, which is made from a refractory metal or refractory alloy acting as glass-contact material. The refractory metal or alloy contains molybdenum, tungsten, tantalum, and/or hafnium. The device of the present invention includes a protective gas reservoir for a protective gas and an automatically operating valve connecting the reservoir with the refining bank so that an inner side of the component that would otherwise be exposed when a pressure rise or a falling glass melt column occurs is protected from oxidation by the protective gas. A process for using the device during refining of the glass melt is also part of the invention.

The invention relates to the field of graphene electrode materials, and in particular relates to a doped graphene electrode material, a macro preparation method as well as an application of the doped graphene electrode material in a high-capacity high-multiplying-power lithium ion battery. In the invention, graphene is taken as a raw material. The preparation method comprises the following steps: controlling the temperature rising speed rate through shielding gas; introducing gas containing nitrogen or boron elements in different concentrations at high temperature so as to realize the doping of heteroatoms of the graphene, and get the nitrogen or boron doped graphene; mixing the doped graphene, conductive carbon black and a bonding agent; adding a solvent; coating the mixture on a current collector after grinding; taking the mixture after drying, shearing and tabletting as a working electrode; adding electrolyte containing a lithium salt by taking a lithium plate as a counter electrode /reference electrode; assembling into a button-type lithium ion half-battery in a glove box; and carrying out constant current charge and discharge tests under the condition of high current density. According to the invention, the electrode stability of the material under the condition of high current density is improved, and the fact that the doped graphene has higher specific capacity and excellent cycle performance in a shorter time is realized.

Disclosed is a pulsed arc welding method using a pulse current of alternately repeating first and second pulses as a weld current, wherein the first pulse and the second pulse have a pulse waveform of a different pulse peak current level and a different pulse width, respectively, and the following conditions are satisfied: peak current of the first pulse (I_p1)=300 to 700A; peak period (T_p1)=0.3 to 5.0 ms; base current I_b1=30 to 200A, base period (T_b1)=0.3 to 10 ms; peak current of the second pulse (I_p2)=200 to 600A; peak period (T_p2)=1.0 to 15 ms; base current (I_b2)=30 to 200A; and base period (T_b2)=3.0 to 20 ms. In this manner, the consumable electrode arc welding using carbon dioxide gas alone or a mixed gas made mainly of carbon dioxide gas as a shield gas can benefit from stabilized welding arc, improved regularity of droplet transfer, and significantly reduced generation rates of spatters and fumes.

The invention discloses a silicon monoxide/silicon/lithium metasilicate composite negative electrode material. The silicon monoxide/silicon/lithium metasilicate composite negative electrode material comprises a silicon monoxide/silicon/lithium metasilicate composite material and an inorganic matter coating layer. The invention also provides a preparation method of the silicon monoxide/silicon/lithium metasilicate composite negative electrode material. The preparation method comprises the following steps: taking silicon monoxide and an inorganic compound of lithium element, mixing and ball-milling the silicon monoxide and the inorganic compound of the lithium element, sintering the obtained mixture in a protection gas environment, and naturally cooling the sintered mixture to obtain the silicon monoxide/silicon/lithium metasilicate composite material; and mixing and ball-milling the silicon monoxide/silicon/lithium metasilicate composite material and sintering the obtained mixture undera protection gas condition. The preparation method of the silicon monoxide/silicon/lithium metasilicate composite negative electrode material has the advantages of simplicity, safety, low cost, and easiness in operation and industrial production, and the obtained composite negative electrode material has the advantages of high reversible capacity, excellent cycle performances and high initial Coulomb efficiency.

The invention relates to an ultrahigh-strength steel laser tailor welded blank and a forming process thereof. The forming process provided by the invention comprises the following steps: carrying out the laser tailor welding on ultrahigh-strength steel and high-strength steel according to the needed shape; then, delivering the obtained welded blank to a furnace filled with a protective gas and heating to 920-940 DEG C to be continued for at least 5 minutes; fully austenitizing; transferring the austenitized welded blank to a press machine to be rapidly molded and formed; cooling to 100-150 DEG C through pressurization quenching; and cooling along room temperature to obtain the needed parts. The hot stamping process of the laser tailor welded blank provided by the invention has the double advantages of the forming and hot stamping forming of the laser tailor welded blank and simultaneously solves the problems that the ultrahigh-strength steel is difficultly applied to the production ofautomobile structural components/framework components in a laser tailor welded blank mode.

The invention discloses a deep reactive ion etching method, which belongs to the technical field of semiconductor manufacturing. The method comprises a plurality of cyclically-performed etching cycles, and each etching cycle comprises an etching step and a polymer deposition step, wherein etching reactive gases are supplied for the etching step, sidewall protective gases are supplied for the polymer deposition step, and in the process of transforming the etching step to the polymer deposition step, the supply times of the etching reactive gas and the sidewall protective gas are overlapped. The invention has the following advantages that: sidewalls of a deep through hole etched by using the deep reactive ion etching method of the invention is good in smoothness; and the etching efficiency is high.