11 results about "Metallography" patented technology

The invention provides a molten pool dynamic simulation model and system for simulating laser drilling based on a level-set method, and the model comprises a two-dimensional molten pool simulation model which comprises heat transfer-laminar flow (two-phase flow) and level-set physical field coupling; on the basis of the confirmed implementation process parameters and material physical property parameters, a molten pool interface simulation metallographic phase under given process operation is compared with an actual metallographic phase, and a heat transfer mathematical model in the laser drilling process is obtained through simulation confirmation; and the three-dimensional thermal-mechanical coupling model is constructed based on a heat transfer mathematical model and further coupled with a solid mechanical physical field, so that temperature distribution and stress distribution at the welding printing position in the laser drilling process are obtained through simulation. The technical problems that in an existing laser drilling welding technology, parameter debugging depends on experience, dynamic monitoring of a molten pool is difficult, and thermal stress prediction means are lacked can be effectively solved, and powerful theoretical support and data basis are provided for optimizing the welding technology and improving the welding quality.

The invention provides a method for quantitatively evaluating a primary banded structure in steel, and belongs to the field of metallography. The method comprises the following steps: selecting an analysis area of a to-be-tested steel sample; performing surface analysis of the analysis elements on the analysis area to obtain a surface distribution diagram of the analysis elements; according to the surface distribution diagram, the element with the most serious segregation zone in the analysis elements is selected as a main segregation element; and according to the segregation zone morphology in the surface distribution diagram of the main segregation element, the extension degree, the area ratio and the morphology parameters of the primary banded structure of the analysis region are evaluated. By organically combining an element segregation band scanned by an electronic probe and the primary banded structure, the primary banded structure represented by alloy elements can be conveniently and quickly represented, the problem that the primary banded structure is difficult to display by a metallographic etching method is solved, the research on the primary banded structure in steel is realized, a new method is formed, and the method is suitable for industrial production. The method is helpful for evaluating the banded structure in the steel, researching the performance of the steel, performing subsequent heat treatment on the steel and processing a product to a certain extent.

The invention relates to the field of metal materials, and discloses a universal high-efficiency metallographic preparation method for metal materials, which comprises the following steps of: (a) roughing a metal sample by using abrasive paper or a grinding disc; (b) finely grinding the metal sample by using a POS / POH (Poly Olefin Sulfonate / Poly Olefin Hydroxide) disc matched with a 9-micron (c) roughly polishing the sample by using weaving type polishing cloth matched with a grinding material with the particle size of 1-3 microns; and (d) finely polishing the metal sample by using polishing cloth matched with a 50nm-1mu m grinding material. The grinding pass can be reduced, the process is greatly shortened, the sample preparation efficiency is improved, batch sample preparation can be realized by matching with automatic equipment, and batch characterization is possible; the usage amount of abrasive paper can be greatly reduced, resources are saved, cost is reduced, and efficiency is improved; and the method has general applicability to metal material samples, and the high-quality metallographic sample can be prepared by only replacing suitable consumables according to the physicochemical properties of metal through four steps.

The present invention relates to a blind hole reliability testing method, equipment, device and system, the method comprising: directing a laser beam toward a circuit board and performing laser heating on the blind hole to apply a thermal field and form a temperature gradient; performing electrical testing, mechanical testing or metallographic testing on the blind hole to determine the reliability of the electrical connection between the conductive column of the connection hole and the lower conductive layer or / and the upper conductive layer. The present invention uses local high-temperature heating with a laser beam to perform energy-saving, efficient, and full-inspection online blind hole reliability testing on the mechanical and electronic connection between the electroplated metal at the bottom of the blind hole and the original metal, filling a global industry gap and allowing the industry to no longer be afraid of blind holes in circuit boards. At the same time, according to the principles of the present invention, due to the existence of a temperature gradient, the local heating temperature of the electroplated metal in the blind hole can be much higher than the temperature that the insulating material of the intermediate insulating layer can withstand. The strictness of the test is much higher than the current industry temperature cycle box test, and has more reliable test results.

The invention discloses a welding joint micro-area fatigue performance testing method, and belongs to the technical field of material fatigue performance testing. The method comprises the following steps: firstly, determining a micro-area microstructure of a welding joint through metallographic phase or electron back scattering diffraction, measuring the length and width of the micro-area, then carrying out a micro-area mechanical property auxiliary test, obtaining hardness and residual stress distribution, and determining whether the micro-area is reasonably divided or not; preparing a fatigue sample which is completely positioned in the micro region; performing cyclic loading on the sample, and synchronously recording mechanical response and fatigue life data; establishing a corresponding relation between macroscopic stress and micro-area stress based on test data, and drawing a micro-area S-N curve; and finally, integrating the micro-area fatigue performance and initial performance distribution, and analyzing a multi-scale correlation mechanism among microstructure evolution, micro-area performance and macroscopic failure. According to the method, the fatigue performance of the local weak area of the welding joint is accurately represented, the limitation of traditional macroscopic overall evaluation is broken through, and a new method is provided for service life prediction and process optimization of a welding structure.

The invention relates to a round steel internal defect positioning device and method. The positioning device comprises a clamp, a rectangular rod, a circular sleeve, a movable rod, a rectangular sleeve and a U-shaped positioning rod. For the round steel with defects invisible to the naked eyes inside, one side of the sawed round steel is used for performing low-power inspection on the defects, the other side of the sawed round steel is used for performing metallographic analysis, scanning electron microscope analysis and other microscopic analysis on the defects, and the positions of the defects can be quickly and accurately determined by utilizing the round steel internal defect positioning device.

The invention discloses a metallographic structure analysis method based on a multi-task collaborative neural network architecture, and belongs to the technical field of material microstructure analysis. The method specifically comprises the following steps: (1) collecting original image data; (2) performing data amplification by adopting a plurality of offline data enhancement modes; (3) constructing a multi-task collaborative neural network architecture which comprises a feature classification network based on deep residual optimization and an adaptive detection network with context sensing capability; (4) implementing a staged migration training strategy, firstly training a classification network to realize metal classification, then freezing feature extraction layer parameters of the classification network, and injecting classification semantic information into a detection network through a dynamic feature fusion module to perform end-to-end training; and (5) based on a pixel-level segmentation result output by the detection network, realizing accurate area measurement of the metallographic structure by adopting a connected region algorithm. According to the method, the model complexity is reduced through a parameter multiplexing mechanism. According to the method, the problems of background complexity sensitivity and the like in traditional metallographic analysis are effectively solved, and technical support is provided for intelligent development of metallography.

The application discloses a CrMoTa series refractory high-entropy alloy metallographic etching liquid and a preparation method thereof, and belongs to the technical field of preparation and detection of refractory high-entropy alloy metallography. According to mass percentage, the metallographic etching liquid contains 16.6-25.4wt% nitric acid, 8.3-12.0wt% hydrofluoric acid, 20-22wt% polyethylene glycol, 0.1-5wt% special additives, and the rest is deionized water. The preparation method is that the deionized water, polyethylene glycol, nitric acid, hydrofluoric acid and special additives are added into a container and stirred uniformly to obtain the etching liquid. The etching liquid can destroy the dense passivation film on the surface of the alloy through the coordination of hydrofluoric acid and the oxidation of nitric acid, can clearly show the grain boundary and grain structure, and solves the problem that the traditional etching liquid cannot effectively etch the alloy with high content of tantalum and molybdenum. The method is simple in operation, low in cost, low in requirement for equipment, good in etching effect, and suitable for rapid metallographic detection of the CrMoTa series refractory high-entropy alloy.

The invention provides an oil and gas pipeline welded joint metallographic determination method and device based on transfer learning, and can be applied to the field of gasoline pipeline maintenance. Based on the method, before specific implementation, according to a preset training rule, a small number of sample metallographic images about the oil and gas pipeline are utilized, a conventional visual image library is combined, and through transfer learning, the oil and gas pipeline can be trained at a relatively low training cost. And training to obtain a preset oil and gas pipeline welded joint metallographic recognition model which is suitable for an oil and gas pipeline maintenance scene and has a relatively good effect. During specific implementation, the preset oil and gas pipeline welded joint metallographic phase identification model can be utilized to identify and determine the metallographic phase type of the target oil and gas pipeline welded joint by processing a target image which is acquired on an oil and gas production and transportation site and at least comprises the welded joint of the target oil and gas pipeline and an adjacent area of the welded joint. Therefore, the method can be well adapted to an oil and gas pipeline maintenance scene, and the metallographic phase type can be efficiently and accurately identified with low data processing cost.

The invention relates to a metallographic etchant for a dissimilar metal welded joint and a metallographic etchant method. The metallographic etchant comprises a metallographic etchant A and a metallographic etchant B, the metallographic etchant A comprises the following components: ferric trichloride, perchloric acid and water; the metallographic etchant B comprises the following components: nitric acid, glacial acetic acid and ethanol; the metallographic phase corrosive liquid A is used for corroding the oxygen-free copper side of a Kovar alloy and oxygen-free copper welded joint, and the metallographic phase corrosive liquid B is used for corroding the Kovar alloy side of the Kovar alloy and oxygen-free copper welded joint. The components of the metallographic etchant are improved, so that one metallographic etchant only reacts with metal on one side, and double-liquid directional corrosion is realized. According to the step-by-step abrasion method, it is ensured that primary battery reaction is not formed in the corrosion process of the two kinds of metal based on the corrosion electrochemical principle, when the metal on one side is corroded, the metal on the other side is not corroded, the metallographic interface structure morphology can be clearly observed, the preparation quality of the sample is remarkably improved, and the preparation cost is reduced. And a high-precision microscopic characterization basis is provided for process optimization.

The application provides a carbonitriding process for GCr15 parts, and steps are as follows: pre-oxidation, strong penetration, diffusion, quenching, hot cleaning, cold cleaning, cold treatment, tempering, taking out GCr15 parts, and air cooling after discharging. The application realizes continuous production by using a continuous mesh belt furnace production line with controllable atmosphere for carbonitriding, improves production efficiency, reduces labor intensity of workers, increases production capacity, reduces gap furnace opening and closing actions, reduces energy consumption, and saves at least 50% of cost compared with ordinary carbonitriding. In addition, carbon potential of each zone in the furnace can be controlled, so that quality stability is ensured. The surface hardness of the GCr15 parts obtained by the heat treatment process of the application can reach 62-65HRC, the core hardness is 61-64HRC, the carbide layer is less than 0.02mm, the carbonitriding layer is greater than 0.4mm, the surface carbon content is 1.15-1.5%, and the carbonitriding metallography can reach level 1.