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35 results about "Gauge length" patented technology

The term ‘gauge length’ denotes the length of a specimen used for testing purposes. The latter is usually taken as the length between the grips for the test.

Ultralow-temperature slow strain mechanical tensile test platform

The invention relates to the technical field of material mechanical property testing, and provides an ultralow-temperature slow strain mechanical tensile test platform which comprises a vacuum Dewar unit, a liquid helium temperature control unit, a slow strain tensile unit, a measuring unit and a control unit, the vacuum Dewar unit comprises a vacuum Dewar body and is used for providing a closed low-temperature test environment; the liquid helium temperature control unit comprises a direct injection module and a recovery module, the direct injection module is used for directly injecting liquid helium to the gauge length section of the sample for cooling, and the recovery module is used for recovering and recycling unevaporated liquid helium; the slow strain stretching unit is used for stretching a sample arranged in the vacuum Dewar body at a low strain rate; the measuring unit is arranged in the vacuum Dewar body and is used for monitoring the temperature, the force value and the strain data of the sample in real time. Liquid helium is used as a cold source, the liquid helium is directly aligned to the gauge length section of the sample through the direct injection module, and compared with a traditional liquid helium steam natural convection heat exchange mode, the heat exchange coefficient is increased, and automatic precise temperature control is achieved.
Owner:TECHNICAL INST OF PHYSICS & CHEMISTRY - CHINESE ACAD OF SCI

Method for testing compression performance through testing machine

The invention discloses a method for testing compression performance through a testing machine, which comprises the following specific steps: placing a sample on the upper end surface of a compression main body, and enabling two end surfaces of the sample to be parallel; after the extensometer is fixed, the testing machine is reset, and the extensometer is reset; starting the testing machine for compression, synchronously acquiring sample load data and average deformation data on two sides by the extensometer, transmitting the data into the testing machine, generating a stress-strain curve by the testing machine, and reading the compression yield strength, the compression elastic modulus and the compression strength from the curve. The extensometers on the two sides are directly hung between the upper cover and the compression main body to form a closed symmetrical measurement chain, so that knife edges on the two sides are located in the same rigid frame, bending deformation is offset, the reading difference is reduced to one tenth of the original value, meanwhile, a load line and a measurement line coincide, a secondary force transmission path is avoided, and the measurement accuracy is improved. And the flexibility of the rack only affects the overall displacement without changing the relative deformation in the gauge length of the extensometer, so that the repeatability of the elastic modulus is remarkably improved.
Owner:ZHEJIANG STATE INSPECTION & TESTING TECH CO LTD

Simple device for drawing gauge length of aluminum alloy circular performance sample

The utility model discloses a simple device for drawing a gauge length of an aluminum alloy circular performance sample, which belongs to the technical field of gauge lengths of aluminum alloy samples, solves the problems that the operation is difficult and the marking is easy to generate errors when the gauge length of the aluminum alloy circular performance sample is manually made at present, and comprises a caliper bracket, a sample bracket and a caliper, a sliding rail is arranged on a caliper support bottom plate, vertical groove-shaped caliper support supporting rods are symmetrically arranged on the two sides of the bottom plate, spring columns are arranged at the bottoms in grooves of the caliper support supporting rods, and springs are arranged on the spring columns. A left sample holder supporting rod and a right sample holder supporting rod of the sample bracket are arranged on the slide rail in a sliding manner; the caliper is provided with a fixed measuring claw and a caliper outer measuring claw in a sliding mode, two sides of the caliper are lengthened to be provided with blank caliper bodies, and two ends of the blank caliper bodies are clamped in the caliper support supporting rod grooves in a sliding mode and abut against the tops of the springs. The marking of various scale distances is accurately realized, and the efficiency and the accuracy of marking the scale distances are greatly improved.
Owner:NORTHWEST ALUMINUM FABRICATION PLANT

Nondestructive testing method for anchoring performance of prestressed steel strand

The application provides a prestressed steel strand anchoring performance nondestructive detection method, and belongs to the technical field of steel strand performance detection, and comprises the following steps: applying a pre-tension force to a steel strand to be detected, unloading to zero after load preservation, so as to eliminate initial disturbance; applying a preset axial tensile load to the steel strand to be detected, the axial tensile load enabling the steel strand to be in an elastic stress state; under the condition of maintaining the axial tensile load, measuring a torsion angle generated by the steel strand within a gauge length; according to the torsion angle, determining a characteristic parameter representing a tensile-torsion coupling characteristic of the steel strand; comparing the characteristic parameter with a preset qualified judgment threshold value, and judging whether the anchoring performance of the steel strand to be detected is qualified based on a comparison result. The prestressed steel strand anchoring performance nondestructive detection method provided by the application realizes nondestructive detection and root-by-root screening of the steel strand.
Owner:XINJI AOSEN STEEL GRP CO LTD

Method for measuring stiffness coefficient of tensile testing machine

The invention belongs to the field of mechanical property detection of metal materials, and particularly relates to a method for measuring a stiffness coefficient of a tensile testing machine, which comprises the following steps of: 1) room-temperature tensile test: measuring the value of elastic modulus E1 of a tensile sample according to the scale length by using an extensometer; stopping the test at the proportional elasticity stage of the tensile sample; unloading the tensile sample; (2) the tensile testing machine adopts the cross beam platform to carry out the room-temperature tensile test again by using the tensile sample according to the scale distance length, and the elastic modulus E2 is measured; and 3) calculating the stiffness coefficient K of the tensile testing machine according to the elasticity modulus values measured twice. The method has the advantages that the stiffness coefficient of the high-rigidity tensile testing machine can be accurately, simply and conveniently measured, and quantitative separation and measurement of linear deformation of the testing machine are realized through twice elastic tensile tests of the same sample.
Owner:ANGANG STEEL CO LTD

Mechanical property gauge length measuring tool

The utility model provides a mechanical property gauge length measuring tool, and relates to the field of mechanical property inspection. The mechanical property gauge length measuring tool comprises a mounting base, a fixing mechanism and a measuring mechanism, a detecting mechanism is arranged below the center of the fixing mechanism, the detecting mechanism comprises a fixing block and a rotating rod, the bottom of the fixing block is fixedly connected with the right side of the top of the mounting base, and the rotating rod is rotationally connected with the fixing block; according to the mechanical property gauge length measuring tool, the detection mechanism is arranged, a rotating block rotates to drive a rotating rod rotationally connected with a fixed block to rotate, the rotating rod rotates to drive a screw rod rotationally connected with a limiting block in a rotating groove to rotate, and the screw rod rotates to drive a moving seat fixedly connected with a clamping block to move to perform stretching detection on a sample; and the original scale distance and the post-fracture scale distance of the test piece in the tensile test can be conveniently obtained through the measuring mechanism, so that the post-fracture elongation can be quickly and conveniently obtained.
Owner:LUZHOU HANFEI AEROSPACE TECH DEV CO LTD

Line drawing device and method for center line and scale distance of dumbbell-shaped tensile sample

The invention relates to a line drawing device and method for a center line and a scale distance of a dumbbell-shaped tensile sample, and the device comprises a base which is provided with a groove for placing the dumbbell-shaped tensile sample; the fool-proof device is an arc-shaped protrusion arranged on the inner wall of the groove, and the arc-shaped protrusion is matched with the dumbbell-shaped tensile sample in outline and used for preventing a non-dumbbell-shaped sample from being placed in the groove; the limiting assembly comprises a longitudinal length positioning frame and a transverse width positioning frame which are respectively arranged along the length direction and the width direction of the groove and are used for limiting the displacement of the sample in the groove; the positioning line drawing assembly comprises a scale distance line blocking edge and a center line positioning blocking edge, the scale distance line blocking edge is arranged in the scale distance length direction of the sample, the center line positioning blocking edge is arranged in the middle in the width direction of the sample, and the scale distance line blocking edge and the center line positioning blocking edge perpendicularly intersect to form a cross-shaped positioning structure. By adjusting the length and the width of the groove and the curvature of the arc section, the device can adapt to various standard dumbbell-shaped samples and has wide applicability.
Owner:SINOMA TECH (HANDAN) WIND TURBINE BLADE CO LTD

A method for detecting a nickel-based superalloy

This application discloses a testing method for nickel-based superalloys, belonging to the field of material purity testing and evaluation. The testing method includes sample preparation: processing the nickel-based superalloy raw material into cylindrical tensile specimens with a gauge length diameter of 6–15 mm, and polishing the surface; room temperature tensile testing: stretching the tensile specimen at room temperature until it fractures; fracture surface analysis: after fracture, observing the fracture surface using an optical microscope and / or scanning electron microscope, measuring the size of non-metallic foreign matter on the fracture surface, and analyzing its composition to complete the detection. This application has the following advantages: high sensitivity: it can detect micro-non-metallic foreign matter with a maximum Feret diameter of less than 10 μm; high efficiency: the fracture surface can be obtained through room temperature tensile testing, eliminating the need for a high-temperature environment and complex fatigue testing; the segmented tensile process can significantly shorten the testing cycle; for a specimen with a working section of approximately 50 mm, the test can be completed in only about 3 hours.
Owner:AVIC BEIJING INST OF AERONAUTICAL MATERIALS

Super-elastic material large strain visual measurement method based on surface grid deformation identification

The invention discloses a hyperelastic material large strain visual measurement method based on surface grid deformation identification, which comprises the following steps: processing a hyperelastic material to be measured into a dumbbell-shaped sample, and constructing uniformly distributed regular grid lines on the surface of a scale distance section of the sample; stretching the sample at a preset stretching rate, and continuously collecting surface grid deformation images of the sample while stretching; identifying the position of each grid line in each frame of image; and according to the position change condition of the corresponding grid lines in the two adjacent frames of images, determining the strain condition of the hyperelastic material at each moment under the preset stretching rate. The invention aims to solve the problems that a traditional measurement method is inaccurate in measurement under the condition of large strain of the hyperelastic material, for example, speckles chapped and deformed in a random speckle sample laying method are difficult to recover, an extensometer cannot obtain local strain and results have uncontrollable factors, and a traditional DIC method is large in measurement error under large strain.
Owner:CHANGAN UNIV

A device for measuring the gauge length of a metal tensile specimen

ActiveCN224681946UScrew threadGauge length
The application belongs to the technical field of inspection and detection, and particularly relates to a metal tensile specimen gauge length measurement auxiliary device, which comprises a bottom plate base, a fixing module, an electromagnetic module, a movable clamping module and a clamping module for driving the clamping module to move to clamp a specimen are arranged on the bottom plate base, the fixing module and the clamping module clamp two ends of the specimen respectively, the electromagnetic module adsorbs to fix the specimen, and the fixing module, the electromagnetic module, the clamping module and the clamping module are arranged on the same straight line; wherein the clamping module comprises a lead screw and a seat plate, the seat plate is fixed vertically on the bottom plate base, the lead screw is threadedly connected with the seat plate, and the end of the lead screw is rotationally connected with the clamping module. The application effectively reduces the measurement error by combining the electromagnetic fixing and mechanical fixing, and improves the reliability and accuracy of the measurement result.
Owner:DEZHOU DEFENG TESTING TECH CO LTD

Method for determining steel bar fracture strain and ECC reinforcing beam flexural capacity under different corrosion rates

The invention relates to a method for determining steel bar fracture strain and ECC reinforced beam flexural capacity under different corrosion rates, which comprises the following steps: carrying out a tensile test on an uncorroded steel bar, and determining a reference proportion; performing corrosion tests and tensile tests with different corrosion degrees on the plurality of steel bars, and establishing a relational expression between the ratio of the corrected measurement scale distance of the corroded steel bars to the original measurement scale distance and the corrosion rate; performing a corrosion test and a tensile test on the reinforcing steel bar according to the corrected measurement scale distance to obtain a real stress-strain relationship of the corroded reinforcing steel bar under different corrosion rates, and performing relationship fitting; determining the steel bar fracture tensile stress; and calculating the flexural capacity of the ECC reinforced beam. According to the method, the problem that the fracture strain result is small due to the fact that the stress of the corroded steel bar is concentrated on the part with the remarkably reduced section and the same measuring scale distance as that of the uncorroded steel bar is selected for the corroded steel bar can be solved, and the accuracy and reliability of the stress-strain relation of the corroded steel bar are improved; and the correctness and the reliability of predicting the bending bearing capacity of the ECC reinforced beam are improved.
Owner:FUJIAN UNIV OF TECH +1

Method, device, equipment, medium and product for testing percentage elongation after fracture of metal material through small punch test

The invention discloses a method, a device, equipment, a medium and a product for testing the percentage elongation after fracture of a metal material through a small punch test, and relates to the technical field of material mechanical property testing. The method comprises the following steps: acquiring a small punch sample set of a target metal material; performing small punch test treatment on the small punch sample set to obtain test information of the target metal material; based on the finite element model of the notched small punch sample, according to the true stress-strain curve and the load-displacement curves corresponding to the small punch samples of various different notched configurations, determining the fracture criterion of the target metal material in the multi-axial stress state; and inputting the true stress-strain curve and the fracture criterion into a preset finite element model of a standard uniaxial tensile sample, simulating a tensile test to measure the gauge length of the fractured tensile sample, and determining the percentage elongation after fracture. According to the method, the standard percentage elongation after fracture of the material can be simply, conveniently and accurately determined.
Owner:EAST CHINA UNIV OF SCI & TECH +1

Multi-rate tensile test method based on velocity correction and adaptive adjustment

The invention relates to the technical field of material mechanical property testing, in particular to a multi-rate tensile test method based on speed correction and self-adaptive adjustment. The method comprises the following steps: firstly, determining a theoretical tensile speed according to collision regulations, and obtaining a real strain rate of a material through a primary test; and correcting the theoretical speed in combination with the scale distance of the sample. Starting from the corrected speed, by comparing the change of the maximum stress of the material at the adjacent rates, adaptively selecting different proportions to adjust the subsequent test speed step by step, and iteratively carrying out until a preset span ratio termination condition is met. Through speed planning and feedback adjustment of the system, an effective stress-strain curve which covers a wide strain rate range and is free of data redundancy can be efficiently obtained with the least test times, the test efficiency and the data validity are remarkably improved, and accurate and reliable material model input is provided for vehicle collision simulation.
Owner:ANGANG STEEL CO LTD

Room-temperature tensile test method for replacing extensometer

The invention belongs to the field of metal material testing, and particularly relates to a room-temperature tensile testing method for replacing an extensometer, the position of a cross beam platform is changed, so that the distance between clamps is larger than the actual distance between the clamps, and the rigid strain of a testing machine in the loading process is counteracted by using the difference between the two. The method has the advantages that the dependence on the extensometer is completely eliminated through mathematical modeling and rigidity compensation of the testing machine; firstly, a shoulder-free strip-shaped sample is combined with high-precision milling or grinding, so that the size consistency of the sample is ensured; secondly, setting the distance between clamps to be equal to the gauge length of the sample and introducing a beam platform position correction formula to accurately offset the elastic deformation of the testing machine in the loading process, so that the real strain of the sample is reversely deduced by directly utilizing beam displacement data, and a stress-strain curve is drawn according to the real strain; therefore, various parameters related to linear deformation and overall deformation can be accurately measured.
Owner:ANGANG STEEL CO LTD

Stretching clamp of universal testing machine

The invention discloses a tensile fixture of a universal testing machine, and relates to the field of sample clamping devices in material testing. The clamp comprises clamp bodies which are oppositely arranged, clamping faces are arranged on the opposite surfaces of the clamp bodies, main anti-skid teeth and auxiliary anti-skid teeth are arranged on the clamping faces, and the distance between the tooth tops of the main anti-skid teeth and the clamping faces is larger than the distance between the tooth tops of the auxiliary anti-skid teeth and the clamping faces. The tooth top angle E of each main anti-skid tooth is 80-100 degrees, the tooth height H of each main anti-skid tooth is 0.6-1.0 mm, and the tooth top of each main anti-skid tooth is provided with a transition arc; the included angle between the front tooth surface of each auxiliary antiskid tooth and the clamping surface datum line is smaller than that between the rear tooth surface of each auxiliary antiskid tooth and the clamping surface datum line; the tooth tops of the auxiliary anti-skid teeth are provided with transition arcs. According to the device, the local pressure stress and damage to the sample are greatly reduced while effective piercing is guaranteed, slippage caused by material stress relaxation is effectively resisted through the synergistic effect of the main teeth and the auxiliary teeth, it is guaranteed that the sample is broken at the gauge length section, and therefore a stable and accurate test result is obtained.
Owner:SHENZHEN DETONGXING ELECTRONICS

A tensile plate-like specimen for strain rate impact fatigue property test of a material

This invention provides a tensile plate-shaped specimen for testing the strain rate impact fatigue properties of materials, relating to the field of material mechanical property testing technology. The plate-shaped specimen includes, along its axial direction: a gauge length section located in the middle of the specimen; both ends of the gauge length section are connected to one end of a square limiting section via transition sections; the other end of the square limiting section is connected to a threaded section. The gauge length section has a cuboid structure, and the cross-section of the square limiting section is a rounded rectangle or a square. The transition section connects the square limiting section and the gauge length section, achieving a smooth transition from the rounded rectangle or square cross-section to the rectangular cross-section of the gauge length section. The threaded section, located at the end of the specimen, is a threaded cylinder used for fixing with a specimen clamp. The plate-shaped specimen of this invention can stably cooperate with impact tensile testing devices, achieve anti-torsional clamping, and meet the testing requirements for different stress concentration factors.
Owner:CHINA AIRPLANT STRENGTH RES INST

High-throughput mechanical testing equipment and method based on DIC technology

The invention relates to a high-throughput mechanical testing device and method based on a DIC technology, and the method comprises the following steps: installing a clamp matched with a to-be-tested material sample on the device, and connecting a clamping mechanism with a strain mechanism; respectively fixing a plurality of material samples to be detected on the clamp; configuring strain parameters and image acquisition parameters; an actuator or a driving system is started to drive the cross beam to move, and tension is synchronously applied to the multiple to-be-tested material samples for synchronous strain; measuring a force value in real time through a force sensor while carrying out strain on the plurality of to-be-measured material samples, and collecting images of scale distance sections of the plurality of to-be-measured material samples through a camera; after the to-be-tested material samples are snapped, performing DIC processing on the acquired images, and calculating strain data of gauge length sections of the to-be-tested material samples; and generating a stress-strain curve of the material sample by combining strain data according to a force value measured in the strain acquisition process, so as to realize high-throughput mechanical test.
Owner:SHANGHAI JIAOTONG UNIV

A method utilizing SiC f Method for testing the tensile proportional limit of SiC composite materials using a high-throughput testing fixture

This invention belongs to the field of material mechanical property testing technology, and relates to a SiC f A high-throughput testing fixture and method for tensile proportional limit of SiC composite materials is presented. For small-sized Y-shaped end specimens, a corresponding fixture is designed to connect multiple specimens end-to-end, and the self-locking mechanism between the specimens and the fixture effectively transfers the testing machine load to the gauge length of each specimen. The tensile stress on each specimen's gauge length is determined through stress analysis, considering the fixture's self-weight. The tensile strain of each specimen is determined based on the average value of strain gauges attached to the front and rear surfaces of the specimen's gauge length during loading. Multiple SiC composites can be tested simultaneously in a single tensile loading operation. f The tensile stress-strain curve of SiC composite specimens is tested to determine the tensile proportional limit and tensile modulus. This greatly improves experimental efficiency and enables the determination of SiC... f High-throughput testing of the tensile proportional limit of SiC composite materials can ensure precise alignment of the specimen with the loading line of the testing machine and eliminate data dispersion sources related to specimen loading.
Owner:AVIC BEIJING INST OF AERONAUTICAL MATERIALS

A testing device and method for tpu multifilament bundle performance

PendingCN122385340APull forceTensile testing
The application discloses a kind of TPU multi-filament harness performance test equipment and method thereof, including outer frame, vertical frame fixed on the outer frame and roll rack fixedly installed on the outer wall of vertical frame;Steel roller is installed in the roll rack, and a plurality of annular isolation grooves are arranged on the circumference of steel roller along the axial direction, each annular isolation groove is used to independently accommodate a TPU silk line and pass in V-shaped type;Stage is movably arranged on the vertical frame, and lifting assembly is installed on the outer wall of vertical frame above the roll rack, and the driving end of lifting assembly is connected with stage.The application utilizes the structure of steel roller, annular isolation groove, lifting assembly, stage, S-type tension sensor and multi-thread single-cylinder compression assembly etc., to complete the real limit tensile test of TPU multi-filament harness in the stroke of short gauge length equipment.
Owner:JINJIANG XINFANG YARN WEAVING CO LTD +1

Parallel test and minimum spacing compensation method for uniaxial tensile elongation after fracture of plate

The invention relates to the technical field of metal material tensile tests, in particular to a parallel test and minimum spacing compensation method for uniaxial tensile elongation after fracture of a plate. The method comprises the following steps: preparing a sample with a gauge length of L, and carrying out equal-interval marking; through at least two parallel tensile tests, the key mark distance at the fracture is measured; selecting a minimum value of key spacing in all tests as a compensation reference value; and for a to-be-tested sample, after the to-be-tested sample is tested under the same marking condition, the corrected percentage elongation after fracture is calculated by utilizing the compensation reference value and a corresponding formula. Through the core means of determining the reference value through the parallel test and performing model compensation, on the premise that an existing efficient marking technology is not changed, system errors caused by mark damage are corrected fundamentally, the accuracy and authenticity of a measurement result are remarkably improved, and the method can be conveniently integrated to an existing test system and has very high engineering practical value.
Owner:ANGANG STEEL CO LTD

Concrete box girder nonlinear damage identification method considering shear hysteresis effect

The invention discloses a concrete box girder nonlinear damage identification method considering a shear hysteresis effect, and the method comprises the steps: estimating the position of a neutral axis of a box girder through long gauge length strain and material performance, and then determining the curvature distribution, bending rigidity and deflection. A simulation result shows that the evaluation parameter (bending rigidity) can clearly and quantitatively reflect the degradation process of the box girder. Meanwhile, the long gauge length strain can reflect global response and can also capture local changes, and the structural response obtained through inversion is highly consistent with the actual measurement result. Compared with a finite element model correction method, the method does not need a finite element model, and can consider nonlinear and shear hysteresis effects; meanwhile, the method is suitable for the whole process of structure failure.
Owner:NANJING TECH UNIV +3

A method for evaluating global and local formability of advanced high-strength steel

The present invention relates to a method for evaluating the global and local formability of advanced high-strength steel, and belongs to the technical field of metal material stamping forming. The technical solution of the present invention is: using a method combining DIC technology with nonlinear numerical fitting, the plastic deformation of the material within the 50mm gauge length section of the uniaxial tensile specimen is divided into two regions: global and local deformation, and the maximum strain that the material can withstand during global and local deformation is found, thereby characterizing the strength of the material's global formability and local formability. The beneficial effects of the present invention are: a more thorough understanding of the material's forming properties, accurate matching of materials for stamping products, high measurement accuracy, simple operation, and low cost.
Owner:TANGSHAN IRON & STEEL GROUP +2

Method for changing running sheet thickness

Provided is a flying thickness change method that can shorten a thickness off-gauge length and reduce tension fluctuation. The flying thickness change method is a method for performing flying thickness change during continuous rolling of a to-be-rolled material (6) by a tandem rolling mill (2), the to-be-rolled material (6) including a preceding material (61) and a succeeding material (62) that are metal sheets and joined to each other. The flying thickness change method includes: continuously measuring a thickness or a sheet speed of the to-be-rolled material (6) in a target inter-stand section between a target stand (for example, a second stand (2B)) as a rolling mill stand at which thickness change is performed and a preceding stand (for example, a first stand (2A)) as a rolling mill stand preceding to the target stand; detecting a thickness change position near a joined portion between the preceding material (61) and the succeeding material (62) based on measurement results of the thickness or tracking the thickness change position based on measurement results of the sheet speed; and changing a roll gap of a target stand in a timing when the thickness change position reaches the target stand.
Owner:JFE STEEL CORP

Tensile specimen gauge length marking device and tensile method

The application discloses a tensile specimen gauge length marking device and a tensile method, which comprises a bearing mechanism, the bearing mechanism comprises two symmetrically arranged driving parts; two symmetrically arranged tensile mechanisms, the tensile mechanism comprises a synchronous assembly fixedly connected with the driving part, a plurality of pushing assemblies and a connecting assembly are arranged in the synchronous assembly, and the synchronous assembly comprises a tensile table; the connecting assembly is provided with a detachable fixing assembly; and the fixing assembly fixedly clamps a specimen. The application can simultaneously perform tensile tests on multiple specimens; when any specimen is broken, the clamping part of the fixed broken specimen can be separated from the tensile table, the remaining specimens can continue to perform tensile tests, the distance moved by the two symmetrically arranged clamping parts is added, the distance at which the tensile specimen is broken is determined, and the distance is recorded. The application not only has simple operation, but also greatly improves the tensile test efficiency of the specimen.
Owner:GUIZHOU ANDA AVIATION FORGING

Device for measuring gauge length of fractured tensile sample

The utility model discloses a device for measuring the scale distance length of a tensile sample after fracture, which comprises a positioning platform, a plurality of measuring devices are arranged on the positioning platform, the measuring devices are detachably arranged on the positioning platform, and each measuring device comprises a base with a U-shaped groove structure. The measuring device comprises a base, frame structures are detachably connected to the base, the frame structures are symmetrically arranged on the two sides of the base, door-type frame structures are formed through the frame structures, a space for measuring the gauge length of a broken circular or plate-shaped tensile sample is formed between the door-type frame structures, and the measuring device further comprises a moving assembly. The measuring device comprises a frame structure and a moving assembly, the moving assembly is detachably provided with a circular or plate-shaped tensile sample, the upper portion of the moving assembly is detachably connected with the circular or plate-shaped tensile sample, the measuring device further comprises a measuring scale detachably connected to the frame structure, and the two sides of the measuring scale are connected to an L-shaped positioning plate through bolts.
Owner:BAOTOU IRON & STEEL (GROUP) CO LTD

A tensile specimen marking machine

The present invention discloses a tensile specimen marking machine, which belongs to the field of mechanical application technology. The marking machine includes a workbench component, a specimen positioning component, a gauge length determining component and a marking component. The workbench component includes a base and a ruler. There are two rows of inverted trapezoidal slides on the base, which are respectively used to install the specimen positioning component and the gauge length determining component. The ruler is used to determine the gauge length. The specimen positioning component includes a tightening slider, a bracket and a thimble, which are used to fix and tighten the tensile specimen to be marked. The gauge length determining component is used to determine the position of the marking on the specimen. The marking component is used to mark the specimen. The marking machine marks the original gauge length of the tensile specimen by marking before the test, measures the gauge length of the specimen after fracture and calculates the elongation after fracture after the test. It is particularly suitable for the situation where the oxide scale of the high-temperature tensile specimen falls off, resulting in the loss of the marking and the inability to measure the gauge length of the specimen after fracture, thereby improving the validity and accuracy of the elongation measurement result.
Owner:INST OF METAL RESEARCH - CHINESE ACAD OF SCI

Method for determining forming limit strain

To achieve a method for determining forming limit strain that is accurate and can be applied to many types of metals.SOLUTION: A method for determining forming limit strain includes: an extending-out forming test conforming to the ISO 12004-2 standard until a fracture part 11 is generated in a test piece 10 of a sheet material; and in the extending-out forming test, continuously photographing the test piece 10 in time series; calculating data of a temporal change in the difference ΔVmax in maximum major strain speed between two gauge lengths L1, L2, on the basis of images of the fracture part 11 of the photographed test piece 10; and by presuming that the time when the difference has increased to a prescribed threshold ΔVth is a local constriction onset time Tth in the calculated temporal change data of the difference ΔVmax, determining the maximum major strain Emax and the minimum major strain Emin at the local constriction onset time Tth as the maximum major strain and the minimum major strain of the sheet material.SELECTED DRAWING: Figure 7
Owner:UACJ CORP

Method and device for continuously predicting strength of engineering size irradiation material

The invention relates to the technical field of strength prediction, in particular to a continuous strength prediction method and device for an engineering size irradiation material. The method comprises the following steps: acquiring first strength data obtained by a non-irradiation tensile test of a first tensile sample at different size points under different size spectrum systems; inputting the cross sectional area of the scale distance section in the first tensile sample and the first intensity data into a non-irradiation intensity prediction model to obtain a first parameter set; obtaining second strength data obtained by a tensile test after irradiation of a second tensile sample at different size points; inputting the cross sectional area of the scale distance section in the second tensile sample, the first parameter set and the second intensity data into the post-irradiation intensity prediction model to obtain a second parameter set; and inputting the cross sectional area of the engineering size irradiation material into the fitted post-irradiation intensity prediction model to obtain predicted intensity data of the engineering size irradiation material. According to the technical scheme, the strength of the engineering size irradiation material can be continuously predicted.
Owner:XIAMEN UNIV