4162 results about "Electron bunches" patented technology

The invention provides a preparation method of a transmission electron microscope ultrathin sample with a cross section of an electron beam sensitive material, which comprises the following steps: selecting a specific region as a to-be-extracted sample region for the electron beam sensitive material by adopting an electron beam imaging technology; depositing a protective layer on the surface of the to-be-extracted sample area by adopting an electron beam and / or an ion beam; bombarding a to-be-extracted sample area by utilizing a high-energy ion beam, extracting an electron beam sensitive material cross section sample from the to-be-extracted sample area, and fixing the extracted sample to a metal bracket; performing pre-thinning treatment on the extracted sample by using a focused ion beam to obtain a first thinned sample of which the thickness is reduced to be less than a first thickness; and transferring the first thinned sample into a micro-beam fixed-point ion thinning system, and carrying out multi-time stepped low-energy ion beam fine thinning treatment on the first thinned sample by using inert gas ion micro-beams to obtain a second thinned sample which is clean in surface and free of a surface ion damage layer and has the thickness reduced to be less than a second thickness, and taking the second thinned sample as a transmission electron microscope ultrathin sample.

The invention relates to a multi-layer composite black film and a preparation method thereof. The multi-layer composite black film is formed by sequentially stacking a base material layer, a multi-layer film system and a top covering layer, the multi-layer film system is formed by alternately stacking a plurality of absorption layers and a plurality of oxide layers, the number of the layers is 7-30, an initial layer is an oxide layer, the refractive indexes of the oxide layers are the same (1.4-1.5), the thickness ratio of the oxide layers to the absorption layers is larger than 2, and the thickness ratio of the top covering layer to the absorption layers is larger than 1. And the thicknesses of the two layers are increased and then reduced from the substrate layer to the top covering layer. A buffer layer with gradually changed oxygen content is arranged between the oxide layer and the absorption layer, and both the oxide layer and the top covering layer are made of silicon dioxide. The preparation method comprises the following steps: providing the substrate layer, alternately depositing the absorption layer and the oxide layer by using a magnetron sputtering or electron beam evaporation process to form a multilayer film system, then forming the top covering layer, controlling parameters such as vacuum degree, power, temperature and the like during deposition, and forming the buffer layer in the same cavity. The multilayer composite black film has the inner surface reflectivity of less than 1% and the appearance surface reflectivity of less than 5%, and is simple in structure and low in preparation cost.

The invention relates to the technical field of regeneration of waste polyester, in particular to a polyester micro-plastic recycling and impurity removing method and equipment. According to the method, the irradiation technology is adopted for treating the polyester micro-plastic, the polyvinyl chloride is removed by combining electron beam irradiation with the specific gravity method, the radiation dosage and time are accurately controlled, the polyvinyl chloride in the polyester micro-plastic can be effectively removed, the color of the polyester micro-plastic is not affected, and the treated polyester micro-plastic can meet the spinning requirement. The equipment is used for realizing the impurity removal method and comprises irradiation treatment equipment, a separation tank, a cleaning tank, a dehydrator and a drying tower. The equipment is simple in structure and convenient to operate, the radiation dosage and time can be accurately controlled in the impurity removal process, the surface temperature of the polyester micro-plastic is effectively controlled, and production and popularization are easy.

The present invention relates to the field of titanium alloy smelting technology and discloses a method for preparing a high-performance two-phase titanium alloy at low cost by melting flat ingots in an electron beam cooling hearth furnace. The method comprises a two-phase titanium alloy, wherein the nominal composition of the two-phase titanium alloy is proportioned, with TC4 titanium alloy return material as the main material, supplemented by an intermediate compensating alloy, and an improved charging method. Subsequently, an electron beam cooling hearth furnace is used to melt the two-phase titanium alloy ingot. The present invention uses TC4 titanium alloy return material as the main material and melts the two-phase titanium alloy ingot in an electron beam cooling hearth furnace to produce a directly rolled two-phase titanium alloy ingot, eliminating the subsequent blanking and forging process. This not only reduces raw material costs but also shortens the process flow, thereby achieving the goal of low-cost production of the two-phase titanium alloy.

The invention discloses a method for preparing titanium alloy flat ingots by the combination of a vacuum consumable skull melting furnace and an electron beam cold hearth furnace. By using a large proportion of TC4 return materials and adopting the combination process of a vacuum consumable skull melting furnace + an electron beam cold hearth furnace, titanium alloy flat ingots with high stability and suitable for direct rolling are prepared. The invention effectively reduces carbon emissions and production costs from the aspects of raw materials and preparation processes, and helps to realize the recycling of titanium resources and the short-process preparation of titanium alloys.

The invention discloses a method for preparing a titanium alloy slab ingot by duplex of a vacuum consumable skull furnace and an electron beam cold bed furnace, and the titanium alloy slab ingot which is high in stability and can be used for direct rolling is prepared by adopting a large-proportion TC4 return scrap through a duplex process of the vacuum consumable skull furnace and the electron beam cold bed furnace. According to the method, carbon emission and production cost are effectively reduced from the aspects of raw materials and the preparation process, and recycling of titanium resources and short-process preparation of the titanium alloy are facilitated.

The invention belongs to the technical field of vacuum coating, and particularly relates to a vacuum coating machine electron gun control method and system.The control method comprises the steps that in the coating process, key real-time parameters reflecting the working state of an electron gun and the evaporation process are continuously collected and fused, and the current coating state is evaluated in real time based on the key real-time parameters; and in combination with preset coating process requirements, an electron beam control target instruction set of a next control period is dynamically generated through a built-in decision mechanism and is sent to a power controller, a focusing coil controller and a scanning coil controller of the electron gun, and the electron gun is driven to adjust the power output, the focusing state and the scanning motion of the electron gun in real time. Through accurate and stable control of the evaporation rate, material characteristic changes are effectively coped with through a strong closed loop of power and the evaporation rate; the dynamically planned scanning path can actively compensate the non-uniformity of the thermal field of the crucible, and beam spot energy distribution is optimized in combination with focusing adjustment, so that the uniformity of the thermal field is remarkably improved.

The invention discloses a method and device for predicting the fatigue life of a high-temperature alloy vacuum electron beam welding structure, and belongs to the technical field of aero-engines. The method comprises the following steps: acquiring fatigue experiment data of a target high-temperature alloy standard sample; extracting the maximum area of an initial defect, a defect shape factor and crack source position information; obtaining a stress intensity factor range considering defect morphological characteristics and a fatigue crack propagation threshold value of a material structure containing initial defects, and correcting a damage tolerance theoretical formula to obtain simulation data; fatigue test data and simulation data are fused to form an initial data set, a fatigue limit is calculated and expanded to the data set, the expanded data set serves as input, training is conducted through a support vector regression method, hyper-parameters are determined through Bayesian optimization, and a fatigue life prediction result of the high-temperature alloy vacuum electron beam welding structure is output. The method provided by the invention can well consider the influence of different morphology defects on the fatigue performance of the welded joint.

The invention relates to a vacuum electron beam welding method for an extra-thick double-sided stainless steel composite blank. The vacuum electron beam welding method comprises the steps that S1, a blank is prepared; s2, processing the surface of the base material carbon steel; s3, processing the surface of the composite stainless steel; s4, assembling and vacuum electron beam direct welding are carried out twice; s5, performing surface anti-oxidation spraying and packaging treatment on the double-sided composite blank after secondary welding; s6, heating the composite blank in a heating furnace, and rolling; and S7, the composite blank is rolled to the thickness required by the product according to the rolling ratio required by the finished product, and the stainless steel + carbon steel + stainless steel extra-thick double-sided stainless steel composite plate can be obtained after cooling. According to the method, the key technical bottleneck of producing the extra-thick double-sided stainless steel composite blank through the vacuum electron beam welding process is solved, particularly, the influence of vacuum electron beam welding magnetic blowing is eliminated, and powerful technical support can be provided for follow-up variety development and stable production.

The invention relates to the technical field of X-ray tube control, and discloses a control method and device for a controllable flying focus X-ray tube, and the method comprises the steps: building an orthogonal electromagnetic deflection system based on an electron beam flight path of the X-ray tube, and the orthogonal electromagnetic deflection system comprises an X-direction electromagnetic coil and a Y-direction electromagnetic coil; creating a conversion relation for converting the target focus position function into an electromagnetic coil current value; executing nonlinear magnetic field response compensation to obtain high-speed switching control signals of the X-direction electromagnetic coil and the Y-direction electromagnetic coil; and performing focus trajectory prediction based on the high-speed switching control signal to obtain a focus motion trajectory formed by the electron beam on the target material, and performing thermal load distribution optimization on the focus motion trajectory to obtain a focus position control scheme for uniform distribution of the surface temperature of the target material. Accurate positioning control of the electron beam on the target material is achieved, and the X-ray imaging quality is improved.

The invention provides a scanning compensation method of electron beam detection equipment, a product and equipment. The method comprises the following steps: carrying out continuous scanning detection by electron beam detection equipment according to a preset scanning direction of a detected surface of a wafer; in the scanning detection process, a workbench bearing the wafer drives the wafer to move in the plane where the detected surface is located in the preset translation direction; the position detection device detects the jitter displacement of the workbench in the displacement process, wherein the jitter displacement is the deviation value of the actual position and the theoretical position caused by mechanical jitter in the displacement process of the workbench; and compensating the scanning waveform of the electron beam detection equipment according to the jitter displacement. Through the method, the electron beam can scan along with the compensated scanning waveform, so that the scanning error caused by mechanical jitter in the displacement process of the workbench is effectively reduced, the image jitter in the scanning result is eliminated, and the scanning result is closer to the real condition of the surface of the wafer.

The invention discloses a sample preparation and characterization method of a rotation angle crystal interface, which is suitable for a sample with dislocation at the interface of two crystals, and comprises the steps of sample preparation and measurement of the relative rotation angle theta of the two crystals. A certain angle is formed between the cutting direction and the interface for sample preparation, a slice is taken out, and the obtained slice has three thin areas including a top material A crystal, a top material A / bottom material B crystal mixing area and a bottom material B crystal; measurement of the rotation angle theta: the electron beam direction is parallel to the rotation axis of the top sample during testing, and the rotation angle theta is directly measured by analyzing crystallographic information of the three thin areas. According to the method, the rotation angle of the top crystal relative to the bottom crystal can be accurately measured through TEM analysis of the three thin regions, and the error-tolerant rate of TEM sample preparation and analysis experiments is improved. In addition, the sample preparation technology can be used for monitoring the change of the physical properties of the sample in mechanics, thermotics, optics, electricity and the like along with the reduction of the size of the sample from the micron level to the nano level.

A tailor-welding, spinning and variable-wall-thickness forming method for a large-sized extension section of a liquid propellant rocket engine, which belongs to the technical field of metal forming. The method comprises: performing laser numerical control machining on a GH3044 superalloy to obtain two chord-tangent circles; performing electron beam welding to obtain a complete circle; performing a vacuum solid solution treatment; performing pre-forming to obtain a shallow dish shape; performing a vacuum solid solution treatment; assembling a variable-wall-thickness flat blank and a spinning mandrel of a first spinning die, and then performing spinning on a spinning machine to form a curved generatrix variable-wall-thickness blank part; performing a vacuum solid solution treatment; and assembling the curved generatrix variable-wall-thickness blank part and a spinning mandrel of a second spinning die, and then performing spinning on the spinning machine to form a curved generatrix variable-wall-thickness part. The present invention is mainly used for the manufacturing of an ultra-large-sized GH3044 extension section of the liquid propellant rocket engine, which has a diameter of 1200 mm and a length of 1500 mm, and the product precision reaches a wall thickness tolerance of + / -0.05 mm for each point and a surface profile of ≤3 mm.

A method of manufacturing a sterile stack of peelable lenses includes coating a first lens (or stack of lenses) with a first adhesive coating, heating the first adhesive coating to initiate curing, exposing the first adhesive coating to ultraviolet light to continue curing, laminating a second lens (or stack of lenses) onto a surface of the first adhesive coating to produce a stack of lenses, coating the second lens with a second adhesive coating, heating the second adhesive coating to initiate curing, exposing the second adhesive coating to ultraviolet light to continue curing, laminating a third lens (or stack of lenses) onto a surface of the second adhesive coating to add the third lens to the stack of lenses, and exposing the stack of lenses to an electron beam to continue curing of the first and second adhesive coatings.

The invention belongs to the technical field of metal composite materials and hydrogen storage and transportation materials, and particularly relates to a high-strength hydrogen-embrittlement-resistant layered metal composite material for hydrogen storage and a preparation method and application of the high-strength hydrogen-embrittlement-resistant layered metal composite material. According to the preparation method, the nickel-saving austenitic stainless steel (NEASS) and the 30CrMo steel are alternately overlapped in a multi-layer mode, and the processes of vacuum electron beam welding, high-temperature hot rolling, accumulative ply rolling, multi-stage heat treatment and the like are combined, so that the composite board with the layer number reaching hundreds of layers, firm interface bonding, excellent mechanical performance and good hydrogen embrittlement resistance is prepared; the technical problem that strength, toughness and hydrogen brittleness resistance of an existing metal material in a high-pressure hydrogen environment are difficult to consider at the same time is solved. The obtained composite material has high strength, high plasticity and excellent hydrogen embrittlement resistance, and is suitable for structural materials of high-pressure hydrogen storage tanks, hydrogen conveying pipelines and other key hydrogen energy equipment.

The invention relates to the field of cyclotrons, and discloses a cavity electron beam welding device and method for a high-frequency cavity of a proton cyclotron, and the device comprises a base which comprises a switching part and two fan-shaped parts; the limiting mechanism comprises first components, a second component and a third component, and the third component, the second component and the two first components jointly define a first limiting space; the first supporting component is detachably arranged on at least one fan-shaped part, and a second limiting space is formed between the first supporting component and the second component; the second supporting part is detachably arranged on one fan-shaped part, and a third limiting space is formed between the second supporting part and the second part; a third support member selectively disposed on an upper side of the second support member; and the lateral limiting piece is arranged on the other side, close to the switching part, of the fan-shaped part, and the lateral limiting piece is detachably connected with the fan-shaped part. The number of welding tools and the welding frequency can be reduced, and the welding efficiency is improved.

The present invention provides a titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing. The chemical composition of the aluminum alloy powder includes, by mass percentage, Cu: 1.8-2.7%, Ni: 0.8-1.4%, Mg: 0-1.8%, Fe: 0.1-1.4%, TiB2 particles 0.1-10%, and the balance is aluminum. The main steps of its preparation method are: melting of the particle-reinforced aluminum alloy preform ingot and gas atomization forming of the particle-reinforced aluminum alloy powder. The block formed by electron beam additive manufacturing using the titanium diboride particle-reinforced heat-resistant aluminum alloy powder of the present invention has no cracks, and the microstructure is uniform and the grains are fine. After heat treatment, the obtained tensile strength is 320 MPa, and the elongation is greater than 10%, which is better than the average level of the mechanical properties of electron beam additive manufacturing aluminum alloys.

The resist composition exhibits a high contrast, improved maximum resolution, and satisfactory sensitivity and line width roughness (LWR) when processed by lithography using high-energy radiation, especially electron beam (EB) and EUV, and a pattern forming process using the resist composition. The resist composition comprising (A) a base polymer containing a polymer comprising repeat units having an acid labile group and repeat units having a carboxy group, (B) an organic solvent, and (C) a hypervalent iodine compound having formula (1):

The invention discloses a metal crack repairing method and device based on an ultrasonic technology. The method comprises the steps that metal powder is selected as brazing filler metal and pretreated; cleaning cracks in the metal base material and spraying a boron nitride coating; mixing an ethanol solution with brazing filler metal powder according to a preset proportion, stirring to form a uniform suspension, injecting the suspension into the crack filling area through a needle tube in a vacuum negative pressure environment, preheating to accelerate solvent volatilization, and only leaving and compacting the brazing filler metal powder; clamping and fixing the base material and putting the base material into a vacuum chamber; electron beam melting is started, snakelike scanning is conducted in the length direction of the crack, and meanwhile ultrasonic vibration is conducted on the crack; and after fusion is completed, ultrasonic vibration is continuously carried out to restrain grain coarsening. Aiming at crack repair of a high-temperature metal part, through the coupling effect of electron beam melting and ultrasonic vibration, the limitation of a single technology is broken through, and a complete and synergistic repair system is formed.

The invention discloses a material deformation collaborative acquisition test method, device and equipment and a storage medium, and relates to the technical field of material testing, and the method comprises the following steps: carrying out EBSD calibration on the sample surface of a to-be-tested sample; preparing speckles on the surface of the sample and carrying out in-situ loading so as to carry out DIC determination; removing speckles on the target to-be-tested sample, and returning to execute the step of EBSD calibration based on the to-be-tested sample after speckle removal until in-situ loading of the target to-be-tested sample reaches a preset loading target; and determining an EBSD test result and a DIC test result based on the obtained measurement results of the internal grain orientation information and the material strain information of each sample to be tested. The method does not need to consider the influence of DIC on EBSD calibration, breaks through the limitation of the electron beam on the size of speckle particles or the size of a DIC observation area in EBSD calibration, and improves the test efficiency of material deformation collaborative collection.

The invention discloses a MeV-level wide-energy-spectrum gamma energy selection amplification imaging system and a design method thereof. The technical problem that an existing gamma ray beam energy selection imaging device is low in detection efficiency is solved. The imaging system comprises a radiation conversion unit, an energy selection beam amplification unit and an imaging unit, the radiation conversion unit is a radiation conversion target and is used for converting gamma rays from a to-be-detected target into electron beams; the energy selection beam amplification unit comprises a collimator, a first magnet and a second magnet which are sequentially arranged along the transmission path of the electron beam; the collimator is used for limiting the collection angle of the electron beam; the parameter specifications of the first magnet and the second magnet are different, the first magnet and the second magnet are respectively used for changing a transmission path of an electron beam through a magnetic field, and a first beam limiting device is arranged between the first magnet and the second magnet and is used for removing electrons which can be dispersed in the y direction and are large in angle; and a second beam limiting device is arranged between the imaging unit and the second magnet and is used for removing electrons which can be dispersed in the x direction and have large angles.

The invention discloses stainless steel vacuum barrel welding equipment and a welding method, and relates to the technical field of welding equipment.The stainless steel vacuum barrel welding equipment comprises a main body, a sealing door is slidably connected to one end of the main body, a limiting mechanism is arranged in the main body, two sets of electric push rods are arranged in the limiting mechanism, and fixing plates are fixed to the two sides of the top end of the limiting mechanism; two sets of metal plates are arranged at one end of the sealing door, the metal plates and the sealing door are elastically connected through a plurality of sets of springs, and a first U-shaped block is fixed to one end of each metal plate. A linear motor is started through a control panel to drive a limiting mechanism to move outwards, a linkage clamping mechanism and a rotary telescopic mechanism are synchronously expanded outwards, electron beam welding is started after an external vacuum pump establishes a vacuum environment, the equipment adopts inner and outer double-side force application to ensure uniform clamping, a shape memory alloy compensates a high-temperature sealing gap, and a spring realizes automatic reset; and sealing failure caused by deformation and thermal deformation of the thin-wall cylinder is effectively prevented.

The invention belongs to the technical field of TC4 alloy additive manufacturing, and discloses an electron beam melting TC4 alloy isotropic optimization method based on staged temperature control HIP, which comprises the following steps of: depositing TC4 alloy powder along the normal direction of a substrate, and printing a part through an electron beam powder bed melting additive manufacturing technology; and then, staged temperature control hot isostatic pressing treatment is carried out on the printed part, and defects generated by printing are closed. According to the method, the hot isostatic pressing (HIP) technology is adopted, under the synergistic effect of the high temperature of 920 DEG C and the high pressure (Ar protection) of 150 MPa, the defects of air holes, incomplete fusion and the like in the TC4 alloy formed through EBM are eliminated through a plastic deformation and diffusion creep mechanism, and the density is remarkably improved. Meanwhile, a metastable martensite alpha'phase is promoted to be decomposed into an equilibrium-state alpha + beta double-phase structure in a high-temperature environment, and alpha-phase grains are moderately coarsened (the average size is increased to 3.12 microns from 1.71 microns).

The invention discloses a high-strength copper-steel double-metal composite material and a preparation method of the high-strength copper-steel double-metal composite material. Copper and steel base materials for preparing the high-strength copper and steel double-metal composite material are selected; the copper base material and the steel base material are welded through the electron beam additive manufacturing technology; scanning a welding seam of the copper-steel bimetallic composite material by using an ultrasonic detection system; analyzing and processing the scanned image through a computer; carrying out secondary treatment on the copper-steel double-metal composite material by adopting a rolling compounding method; carrying out quenching treatment on the copper-steel double-metal composite material; inspecting the performance of the high-strength copper-steel bimetallic composite material; and storing the prepared data to a cloud end through a computer. According to the method, the electron beam additive manufacturing technology and the rolling composite method are combined, the strength of the copper-steel composite material can be improved in the preparation process, the composite material is detected through an ultrasonic detection system, the percent of pass of the composite material can be screened, and the performance of the composite material can be further enhanced through annealing treatment.

The invention discloses a TiAl alloy electron beam selective melting and shot peening strengthening in-situ compounding manufacturing method and device, and relates to the technical field of additive manufacturing. The method comprises the following steps: establishing a three-dimensional digital model of a to-be-printed part, and performing slicing and layering to obtain layered scanning data; under the vacuum condition, TiAl alloy powder is spread on the preheated base plate according to the set thickness, and a powder bed is formed; according to the layered scanning data, scanning and melting the powder bed through a focused electron beam, completing single-layer scanning and melting, completing scanning and melting layer by layer until the part is printed and cooled, and recovering unmelted TiAl alloy powder; and under the vacuum condition, the surface of the printed part is scanned and heated through a defocusing electron beam, TiAl alloy powder is adopted as shot blasting powder, the surface of the heated part is subjected to microparticle shot blasting strengthening treatment, after the treatment is finished, cooling is conducted, scattered shot blasting powder is recycled, and the finished TiAl alloy part is obtained. By means of the collaborative process design of electron beam selective melting and in-situ high-temperature microparticle shot blasting and device integration, the problems that in TiAl alloy additive manufacturing, cracking is prone to occurring, and the strengthening effect is poor are solved.

The invention discloses an electron beam composite scanning filling melting forming method and device, and relates to the technical field of additive manufacturing. A melting forming method for electron beam composite scanning filling comprises the following steps that a three-dimensional digital model of a part to be printed is established and sliced and layered, and layered scanning data are obtained; dividing a contour edge area and an internal area of the section of the part based on the hierarchical scanning data; based on a random discrete point algorithm, generating a random discrete point scanning path of the contour edge area; generating a continuous line scanning filling path of the internal region based on a parallel equidistant line filling method; in the contour edge area, according to a random discrete spot scanning path, a pulsed electron beam is adopted for spot scanning, filling and melting; and in the internal area, according to a continuous line scanning filling path, a focused electron beam is adopted for line scanning filling melting, single-layer filling melting is completed, and then filling melting is completed layer by layer till the part is formed. According to the method, collaborative optimization of the surface quality and the printing efficiency is achieved, and the problem that at the present stage, the surface roughness of an electron beam powder bed printing part is too high is solved.

The invention relates to a femtosecond gamma ray pulse generation device, which comprises a femtosecond order electron beam slice generation system, a cavity, a Compton scattering laser system and collimation equipment, and is characterized in that the femtosecond order electron beam slice generation system, the cavity and the collimation equipment are sequentially arranged along a first axis; the femtosecond-order electron beam slicing system is used for generating femtosecond-order electron beams with high-density slices, the cavity is used for providing an interaction cavity, and the Compton scattering laser system is used for generating pulse type laser. The pulse type laser and the electron beam with the high-density slices in the femtosecond order are subjected to Compton scattering in the interaction cavity so as to generate a gamma-ray pulse in the femtosecond order; the collimation device is used for carrying out collimation on the femtosecond order gamma ray pulse.

The invention discloses an electron beam selective melting additive manufacturing method for an Al-Si-Mg alloy. The method comprises the steps that Al-Si-Mg alloy powder for 3D printing is provided; a bottom plate for forming is loaded into electron beam 3D printing equipment, and the height of the bottom plate is adjusted; the bottom plate is preheated to the temperature not exceeding 480 DEG C under the vacuum condition, and heat preservation is conducted; al-Si-Mg series alloy powder is evenly spread on a preheated bottom plate, and electron beam printing including the following processes of preheating before a powder bed, selective melting and preheating after the powder bed is carried out; and the bottom plate height lowering, powder laying and electron beam printing are repeated till all layers are printed. Stable and high-quality forming of the Al-Si-Mg series aluminum alloy is achieved by designing the matching property of the powder characteristics and the process parameters in the electron beam selective melting additive manufacturing Al-Si-Mg series alloy.

The invention discloses a deformable electron beam lithography machine beam spot size calculation method and system, and the method comprises the steps: S1, employing a hyperbolic cosine function as a primary function according to a relation curve between the current intensity and the beam spot position, and constructing a composite function model through translation and superposition; s2, assuming that the observation value is a noise version of the composite function model, and establishing a likelihood function; a logarithm likelihood function is maximized and converted into a minimum residual sum of squares, partial derivatives of the minimum residual sum of squares about all parameters are solved, and a gradient equation set is obtained; s3, calculating the measurement signal, and extracting key feature points in the curve; calculating an initial parameter value according to the position of the feature point: taking the initial parameter as input, and iteratively solving a gradient equation set to obtain an exact solution of each parameter; and S4, calculating the actual size, the central position and the sharpness of the left and right edges of the electron beam spot according to the exact solutions of the parameters. The method has the advantages of high calculation precision and the like.

The invention discloses a preparation method for smelting a high-rhenium-molybdenum alloy pipe. The method comprises the following steps: 1, uniformly mixing Mo powder and Re powder, performing cold isostatic pressing, and sintering to obtain a high-rhenium-molybdenum alloy sintered blank; 2, carrying out vacuum electron beam smelting for many times to obtain a smelted high-rhenium molybdenum alloy cast ingot; 3, performing high-temperature extrusion combination and forging to obtain a smelted high-rhenium molybdenum alloy bar; 4, performing deep hole drilling, honing and machining treatment to obtain a smelted high-rhenium molybdenum alloy pipe blank; and 5, performing multi-pass high-temperature rolling, intermediate heat treatment, surface treatment and finished product heat treatment to obtain the smelted high-rhenium molybdenum alloy pipe. According to the method, repeated vacuum electron beam smelting is adopted, and repeated pressure machining such as high-temperature extrusion, forging and high-temperature rolling is combined, so that the purity and component uniformity of the smelted high-rhenium molybdenum alloy pipe are improved, the structure is uniform, the mechanical property is excellent, and higher dimensional precision and surface quality are obtained; the material is suitable for the fields of cladding pipes, heat pipes, medical implants and the like in nuclear reactors.