CN118190676A - Hard and brittle material strength measuring device and method based on visual alignment - Google Patents
Hard and brittle material strength measuring device and method based on visual alignment Download PDFInfo
- Publication number
- CN118190676A CN118190676A CN202410378310.0A CN202410378310A CN118190676A CN 118190676 A CN118190676 A CN 118190676A CN 202410378310 A CN202410378310 A CN 202410378310A CN 118190676 A CN118190676 A CN 118190676A
- Authority
- CN
- China
- Prior art keywords
- sample
- pressure head
- ring gauge
- bracket
- brittle material
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000463 material Substances 0.000 title claims abstract description 38
- 230000000007 visual effect Effects 0.000 title claims abstract description 28
- 238000000034 method Methods 0.000 title claims abstract description 24
- 238000012360 testing method Methods 0.000 claims abstract description 43
- 230000007547 defect Effects 0.000 claims abstract description 28
- 238000013142 basic testing Methods 0.000 claims abstract description 6
- 238000007373 indentation Methods 0.000 claims description 10
- 238000009417 prefabrication Methods 0.000 claims description 10
- 238000003825 pressing Methods 0.000 claims description 8
- 238000002474 experimental method Methods 0.000 claims description 7
- 238000012545 processing Methods 0.000 claims description 4
- 238000005336 cracking Methods 0.000 claims description 3
- 241000589562 Brucella Species 0.000 claims description 2
- 229910010293 ceramic material Inorganic materials 0.000 claims description 2
- 230000003287 optical effect Effects 0.000 claims description 2
- 239000005304 optical glass Substances 0.000 claims description 2
- 238000010998 test method Methods 0.000 description 11
- 238000005259 measurement Methods 0.000 description 8
- 238000013001 point bending Methods 0.000 description 8
- 239000011521 glass Substances 0.000 description 6
- 238000005452 bending Methods 0.000 description 5
- 238000007678 ball-on-ring test Methods 0.000 description 4
- 238000007545 Vickers hardness test Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000013101 initial test Methods 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910021421 monocrystalline silicon Inorganic materials 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000009966 trimming Methods 0.000 description 1
- 238000011179 visual inspection Methods 0.000 description 1
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
The invention discloses a hard and brittle material strength measuring device and a method based on visual alignment, wherein the measuring device comprises a basic test unit, a visual positioning unit and a sample fine adjustment unit, the basic test unit comprises a universal mechanical testing machine, a pressure head, a ring gauge and a bracket, the visual positioning unit comprises a high power micro lens, a CCD camera, a display, a coaxial light source and a universal focusing bracket, and the sample fine adjustment unit comprises a base, a sliding track, a micrometer and a sample clamping platform. The visual positioning device and the fine adjustment device are integrated, so that an experimenter can observe and finely adjust the sample on the same device, the accurate alignment of the center of the pressure head and the defect concentration area of the tensile surface of the sample is realized, and the accuracy of the strength test is improved. The invention uses a simple fine adjustment device, is convenient to operate, and does not need excessively complex automatic control. The position of the sample can be simply and rapidly adjusted, and the strength test efficiency is improved.
Description
Technical Field
The invention belongs to the field of measurement of strength of hard and brittle materials, and particularly relates to a device and a method for measuring strength of hard and brittle materials based on visual alignment.
Background
The hard and brittle material has the properties of high strength, high temperature resistance, abrasion resistance, corrosion resistance and the like, is widely applied to the fields of semiconductors, aerospace, instruments and meters and the like, and becomes an ideal choice for a plurality of high-end applications. However, since the brittle material is highly brittle, various defects such as scratches, cracks, etc. are generated on the surface and subsurface during the processing thereof, and the presence of such defects directly reduces the strength of the material, thereby generating a series of problems during the processing and use, such as breakage and damage of the material due to insufficient strength, and reducing the service performance and life of the device or member. Therefore, in order to ensure that the hard and brittle material can work safely and reliably in practical application, accurate measurement and evaluation of the strength of the hard and brittle material are of great importance.
The currently common methods for measuring the strength of the hard and brittle materials are a uniaxial bending test method and a biaxial bending test method. The uniaxial bending test method comprises a three-point bending test method and a four-point bending test method, and the Ball-on-ring test method in the biaxial bending test method is more commonly used.
The three-point bending test method is simple and feasible, has low cost and is a strength measurement method widely applied at present. However, because the three-point bending loading mode is concentrated, the stress distribution is uneven, and the middle parts of the upper edge and the lower edge of the sample are in the maximum stress area, the defects of the edges of the sample caused by slicing can lead to the breakage of the three-point bending test in advance, so that the intensity measurement result is seriously lower, and the sample preparation process of the sample without the edge defects is very complex.
The four-point bending test method is characterized in that a loading roller is added on the basis of the three-point bending test method, so that compared with the three-point bending test method, the stress distribution is more uniform, the influence of boundary effect is reduced to some extent, the experimental result is more accurate, but the influence of the edge defect of the sample is still less than the actual strength of the sample, and the strength test result is still less than the actual strength of the sample.
The Ball-on-ring test method is a biaxial bending test method, in which the edge defect of the sample does not cause stress concentration effect in the center of the sample, so that the strength test result is more accurate. However, in the Ball-on-ring test method, the offset distance between the center of the pressure head and the defect concentration area of the tensile surface of the sample has a great influence on the experimental strength result. When the center of the pressure head deviates from the defect concentration area of the tensile surface of the sample, the strength measurement result is increased, meanwhile, the discreteness of the strength measurement result is increased, and the experimental repeatability is poor. In particular, in experiments in which crack depth and strength relationship calibration is performed by an indentation pre-crack test, the indentation position needs to be strictly aligned with the center of the indenter. In the current practical experiment, the center of the pressure head is aligned only by visual inspection, the actual offset distance of the center of the pressure head can be referred to as 0.5mm, and according to the 'research on correlation between the intensity and the surface defect of a ground monocrystalline silicon wafer' published by the university paper in Tian Yuxin 2020, the influence of the offset of the pressure head on the intensity test result in the Ball-on-ring experiment test is researched, and when the offset of the center of the pressure head is 0.5mm, the intensity measurement difference ratio is 9.85%. Therefore, in order to improve the accuracy of the strength test results, it is necessary to precisely align the center of the indenter with the concentrated region of the tensile face defects of the test specimen.
In summary, the existing Ball-on-ring test method is accurate in test, but still lacks a hard and brittle material strength measurement device and method capable of solving the problem of accurate alignment of the center of a pressure head and a defect concentrated area of a sample tensile surface.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a device and a method for measuring the strength of a hard and brittle material based on visual alignment, which can accurately measure the strength of the hard and brittle material and accurately position a pressing head and any position of a sample according to requirements.
In order to realize the functions, the technical scheme of the invention is as follows:
a hard and brittle material strength measuring device based on visual alignment comprises a basic test unit, a visual positioning unit and a sample fine adjustment unit.
The basic test unit comprises a universal mechanical tester, a pressure head, a ring gauge and a bracket, wherein the pressure head is arranged at the center of a cross beam of the universal mechanical tester and the direction of the pressure head is downward; the ring gauge is positioned above the bracket; the upper surface of the ring gauge is used for placing a sample, and the center hole of the ring gauge is aligned with the center of the pressure head through a universal mechanical testing machine; the support is connected with the universal mechanical testing machine through bolts;
The visual positioning unit comprises a high-power micro lens, a CCD camera, a display, a coaxial light source and a universal focusing bracket. The objective lens end of the high power micro lens is positioned below the bracket; the CCD camera is a high-definition electron microscope camera and is connected with the eyepiece end of the high-power micro-lens and the display through a USB interface; the coaxial light source is connected with the objective lens end of the high power micro lens; the universal focusing bracket is connected with the high power micro-lens; the visual positioning unit is used for observing the relative positions of the defect concentration area of the tensile surface of the sample and the central hole of the ring gauge.
The sample fine adjustment unit comprises a base, a sliding rail, a micrometer and a sample clamping platform. The base is positioned above the bracket and provides support; the sliding rail is positioned above the base and moves along the horizontal direction; the micrometer is fixed on the sliding rail and is adjusted by a manual adjusting knob; the sample clamping platform is positioned on the upper surface of the ring gauge, connected with the sliding track and used for clamping a sample to be tested; the sample fine adjustment unit can realize accurate adjustment of the sample position.
A working method of a hard and brittle material strength measuring device based on visual alignment comprises the following steps:
A. Alignment of the ram center and ring gauge center hole
The pressure head is arranged on a universal mechanical testing machine, the support is connected with the universal mechanical testing machine by using bolts, and the ring gauge is placed above the support. And pressing the pressure head into the ring gauge center hole through a universal mechanical testing machine, and simultaneously moving the ring gauge to realize the accurate alignment of the pressure head center and the ring gauge center hole.
B. determining the position of a ring gauge center hole through a visual positioning unit
The objective lens end of the high power micro-lens is connected with the coaxial light source, the eyepiece end of the high power micro-lens is connected with the CCD camera, and the CCD camera is connected with the display through the USB interface. And the high power micro lens is arranged under the ring gauge through the universal focusing bracket. And focusing the high power micro lens by adjusting the universal focusing bracket, and positioning and marking the position of the ring gauge center hole in the display.
C. Mounting sample
The sample clamping platform and the sliding rail are connected with the bracket through the base, and the sample is placed in the sample clamping platform.
D. Alignment of specimen stretching surface defect concentration zone and ring gauge central hole
And adjusting the micrometer, horizontally moving the sample clamping platform, observing the display, and moving the defect concentration area of the sample stretching surface to the marking position of the ring gauge central hole in the display. At this time, the defect concentration area of the sample stretching surface, the center hole of the ring gauge and the center of the pressure head are positioned on the same vertical line, and alignment is completed.
E. hard brittle material strength test
And (3) running an intensity test experiment program, setting the downward moving speed of the pressure head, and loading the sample by the downward moving of the pressure head at a fixed speed until the sample cracking pressure head stops moving, reading the maximum load value in the loading process, calculating the intensity value of the hard and brittle material, and finishing the intensity test of the hard and brittle material.
Further, the hard and brittle material includes optical glass, single crystal material and ceramic material.
Further, the pressure head comprises a Brucella pressure head, a Vickers pressure head, a Knoop pressure head, a triangular pyramid pressure head and a self-defined shape pressure head.
Further, the defect concentration area of the sample stretching surface comprises a residual damage concentration area and a prefabricated damage area of the sample on the surface of the sample after the sample stretching surface is acted by external load.
Further, the sample prefabrication damage area comprises an indentation experiment prefabrication crack area, a grinding experiment prefabrication damage area and a laser processing prefabrication damage area.
Further, the center of the pressure head is precisely aligned with the defect concentration area of the sample stretching surface, namely the defect concentration area of the sample stretching surface, the center hole of the ring gauge and the center of the pressure head are positioned on the same vertical line.
Further, the high power micro lens comprises an electron microscope and an optical microscope.
Compared with the prior art, the invention has the following beneficial effects:
1. The visual positioning device and the fine adjustment device are integrated, so that an experimenter can observe and finely adjust the sample on the same device, the accurate alignment of the center of the pressure head and the defect concentration area of the tensile surface of the sample is realized, and the accuracy of the strength test is improved.
2. The invention uses a simple fine adjustment device, is convenient to operate, and does not need excessively complex automatic control. The position of the sample can be simply and rapidly adjusted, and the strength test efficiency is improved.
3. The invention uses the high-power microscope, can rapidly and conveniently observe the microscopic morphology of the surface of the sample, can monitor the change of the surface of the material in real time, and can move the sample to any position of the working table surface through the fine adjustment device, thereby widening the experimental application range.
Drawings
Fig. 1 is a schematic view of the structure of the device of the present invention.
Fig. 2 is a schematic diagram of a sample trimming unit.
FIG. 3 is a schematic illustration of the alignment of the ram center, specimen stretch surface defect concentration zone and ring gauge center hole.
In the figure: 1.2, a pressure head, 3, a ring gauge, 4, a bracket, 5, a high power micro lens, 6, a CCD camera, 7, a display, 8, a bolt, 9, a universal focusing bracket, 10, a coaxial light source, 11, a base, 12, a micrometer, 13, a sliding track, 14 and a sample clamping platform.
Detailed Description
The invention will now be described in detail with reference to the drawings and to specific embodiments.
Embodiments of the invention are as follows:
And (3) prefabricating cracks on the K9 glass through the Vickers indentation, obtaining the strength value of the K9 glass after prefabrication cracks through strength test, and calibrating the relation between the depth of the K9 glass cracks and the strength.
The initial test specimen was a 10X 0.5mm K9 glass block, and the test specimen was subjected to double-sided finish polishing, and a crack was preformed by carrying out a Vickers indentation test at the center of the surface of the test specimen, with a Vickers indentation load of 100gf, and a load holding time of 15s. In the embodiment, the purpose of accurately aligning the center of the pressing head 2 with the indentation position of the stretching surface of the sample is achieved by adjusting the indentation position of the stretching surface of the sample, the center hole of the ring gauge 3 and the center of the pressing head 2 to the same vertical line. The center of the ram 2 and the center hole of the ring gauge 3 are first aligned. The ram 2 is mounted on the universal mechanic testing machine 1, the bracket 4 is connected with the universal mechanic testing machine 1 by using bolts 8, and the ring gauge 3 is placed above the bracket 4 as shown in fig. 1. Starting the universal mechanical testing machine 1, moving the pressure head 2 downwards, simultaneously moving the ring gauge 3, pressing the pressure head 2 into the center hole of the ring gauge 3 until the force sensor has numerical variation, and finishing the accurate alignment of the center of the pressure head 2 and the center hole of the ring gauge 3. Secondly, the position of the central hole of the ring gauge 3 is determined through a visual positioning unit, the objective lens end and the eyepiece end of the high power micro lens 5 are respectively connected with a coaxial light source 10 and a CCD camera 6, the CCD camera 6 is connected with a display 7, and the high power micro lens 5 is installed under the ring gauge 3 by utilizing a universal focusing bracket 9, as shown in fig. 1. And adjusting a universal focusing bracket 9 to focus the high power micro lens 5, and positioning and marking the position of the central hole of the ring gauge 3 in the display 7. After that, the sample is mounted, the sample holding platform 14 and the sliding rail 13 are connected with the bracket 4 through the base 11, as shown in fig. 2, the sample is placed in the sample holding platform 14, and the damaged surface of the prefabricated indentation of the sample is downward. Then the micrometer 12 is adjusted, the sample clamping platform 14 is horizontally moved, the display 7 is observed, and the indentation position of the stretching surface of the sample is moved to the marking position of the central hole of the ring gauge 3. At this time, the indentation position of the tensile surface of the sample, the central hole of the ring gauge 3 and the center of the pressing head 2 are positioned on the same vertical line, and alignment is completed as shown in fig. 3. And (3) running an intensity test experiment program, clicking a zero clearing and calibrating key of the universal mechanical testing machine 1, and calibrating a force sensor in the universal mechanical testing machine 1. Setting the downward moving speed of the pressure head 2 to be 0.5mm/min, moving the pressure head 2 downward at the speed of 0.5mm/min to load the sample until the sample cracking pressure head 2 stops moving, reading the maximum load value in the loading process through the display 7, calculating the strength value of the hard and brittle material, and repeating the test for ten groups to obtain the strength test result of the material. In the example, ten groups of samples are tested to obtain K9 glass with the average intensity value of 89.902MPa and the intensity measurement difference value ratio of less than 3%, and after the center of the pressing head 2 and the indentation position of the tensile surface of the sample are aligned by the visual alignment device, the dispersion of the intensity value of the K9 glass is smaller, and the intensity test accuracy is improved.
The present invention is not limited to the present embodiment, and any equivalent concept or modification within the technical scope of the present invention is listed as the protection scope of the present invention.
Claims (8)
1. A hard brittle material intensity measuring device based on vision alignment, characterized in that: the device comprises a basic test unit, a visual positioning unit and a sample fine adjustment unit;
The basic test unit comprises a universal mechanical tester (1), a pressure head (2), a ring gauge (3) and a bracket (4), wherein the pressure head (2) is arranged at the center of a cross beam of the universal mechanical tester (1) and is downwards oriented; the ring gauge (3) is positioned above the bracket (4); the upper surface of the ring gauge (3) is used for placing a sample, and a central hole of the ring gauge (3) is aligned with the center of the pressure head (2) through the universal mechanical testing machine (1); the bracket (4) is connected with the universal mechanical testing machine (1) through bolts (8);
The visual positioning unit comprises a high-power micro lens (5), a CCD camera (6), a display (7), a coaxial light source (10) and a universal focusing bracket (9); the objective lens end of the high power micro lens (5) is positioned below the bracket (4); the CCD camera (6) is a high-definition electron microscope camera, is connected with the eyepiece end of the high-power micro lens (5) and is connected with the display (7) through a USB interface; the coaxial light source (10) is connected with the objective lens end of the high power micro lens (5); the universal focusing bracket (9) is connected with the high power micro lens (5); the visual positioning unit is used for observing the relative positions of the defect concentration area of the tensile surface of the sample and the central hole of the ring gauge (3);
The sample fine-tuning unit comprises a base (11), a sliding rail (13), a micrometer (12) and a sample clamping platform (14); the base (11) is positioned above the bracket (4) and provides support; the sliding rail (13) is positioned above the base (11) and moves along the horizontal direction; the micrometer (12) is fixed on the sliding track (13) and is adjusted by a manual adjusting knob; the sample clamping platform (14) is positioned on the upper surface of the ring gauge (3), connected with the sliding track (13) and used for clamping a sample to be tested; the sample fine adjustment unit can realize accurate adjustment of the sample position.
2. A method of operating a visual alignment-based hard and brittle material strength measuring device according to claim 1, wherein: the method comprises the following steps:
A. The center of the pressure head (2) is aligned with the center hole of the ring gauge (3)
The method comprises the steps of installing a pressure head (2) on a universal mechanical testing machine (1), connecting a bracket (4) with the universal mechanical testing machine (1) by using bolts (8), and placing a ring gauge (3) above the bracket (4); pressing the pressure head (2) into the center hole of the ring gauge (3) through the universal mechanical testing machine (1), and simultaneously moving the ring gauge (3) to realize the accurate alignment of the center of the pressure head (2) and the center hole of the ring gauge (3);
B. determining the position of a central hole of the ring gauge (3) through a visual positioning unit
The objective lens end of the high power micro lens (5) is connected with the coaxial light source (10), the eyepiece end of the high power micro lens (5) is connected with the CCD camera (6), and the CCD camera (6) is connected with the display (7) through the USB interface; the high power micro lens (5) is arranged right below the ring gauge (3) through the universal focusing bracket (9); focusing the high power micro lens (5) by adjusting the universal focusing bracket (9), and positioning and marking the position of the central hole of the ring gauge (3) in the display (7);
C. Mounting sample
Connecting a sample clamping platform (14) and a sliding rail (13) with a bracket (4) through a base (11), and placing a sample in the sample clamping platform (14);
D. Alignment of defect concentration area of sample stretching surface and central hole of ring gauge (3)
Adjusting a micrometer (12), horizontally moving a sample clamping platform (14), observing a display (7) at the same time, and moving a defect concentration area of a sample stretching surface to a marking position of a central hole of a ring gauge (3) in the display (7); at the moment, the defect concentration area of the sample stretching surface, the central hole of the ring gauge (3) and the center of the pressure head (2) are positioned on the same vertical line, so that alignment is completed;
E. hard brittle material strength test
And (3) running an intensity test experiment program, setting the downward moving speed of the pressure head (2), moving the pressure head (2) downward at a fixed speed to load the sample until the sample cracking pressure head (2) stops moving, reading the maximum load value in the loading process, calculating the intensity value of the hard and brittle material, and finishing the intensity test of the hard and brittle material.
3. The method of operating a visual alignment-based hard and brittle material strength measuring device according to claim 2, wherein: the hard and brittle materials include optical glass, monocrystalline materials and ceramic materials.
4. The method of operating a visual alignment-based hard and brittle material strength measuring device according to claim 2, wherein: the pressure head (2) comprises a Brucella pressure head (2), a Vickers pressure head (2), a Knoop pressure head (2), a triangular pyramid pressure head (2) and a self-defined shape pressure head (2).
5. The method of operating a visual alignment-based hard and brittle material strength measuring device according to claim 2, wherein: the defect concentration area of the sample stretching surface comprises a sample surface and subsurface residual damage concentration area and a sample prefabrication damage area after the sample stretching surface is acted by external load.
6. The method of operating a visual alignment-based hard and brittle material strength measuring device according to claim 2, wherein: the sample prefabrication damage area comprises a prefabrication crack area through indentation experiments, a prefabrication damage area through grinding experiments and a prefabrication damage area through laser processing.
7. The method of operating a visual alignment-based hard and brittle material strength measuring device according to claim 2, wherein: the center of the pressure head (2) is precisely aligned with the defect concentration area of the sample stretching surface, namely the defect concentration area of the sample stretching surface, the center hole of the ring gauge (3) and the center of the pressure head (2) are positioned on the same vertical line.
8. The method of operating a visual alignment-based hard and brittle material strength measuring device according to claim 2, wherein: the high power micro lens (5) comprises an electron microscope and an optical microscope.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410378310.0A CN118190676A (en) | 2024-03-29 | 2024-03-29 | Hard and brittle material strength measuring device and method based on visual alignment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410378310.0A CN118190676A (en) | 2024-03-29 | 2024-03-29 | Hard and brittle material strength measuring device and method based on visual alignment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118190676A true CN118190676A (en) | 2024-06-14 |
Family
ID=91397914
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410378310.0A Pending CN118190676A (en) | 2024-03-29 | 2024-03-29 | Hard and brittle material strength measuring device and method based on visual alignment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118190676A (en) |
-
2024
- 2024-03-29 CN CN202410378310.0A patent/CN118190676A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10024776B2 (en) | Apparatus for in-line testing and surface analysis on a mechanical property tester | |
| CN109781516B (en) | Clamp for material strain in-situ EBSD observation test and test method | |
| CN106525571B (en) | Microscope stretcher suitable for optical microscope | |
| KR100582015B1 (en) | Superfine indentation tester | |
| CN109342246B (en) | Method and device for rapidly evaluating wear resistance of coating sample array | |
| CN105136029A (en) | Adjustment method for centering and parallelism between three-point bending sample and clamp | |
| US20170067735A1 (en) | Apparatus for In-Line Test and Surface Analysis on a Mechanical Property Tester | |
| CN111965018A (en) | Ceramic-based fiber bundle composite material transverse stretching matrix crack experimental device and method | |
| CN108398344B (en) | Friction wear test device capable of observing fatigue crack growth inside material in situ | |
| CN216925477U (en) | Wafer rod detection device | |
| CN106644715B (en) | Portable scratch-in test system | |
| CN118190676A (en) | Hard and brittle material strength measuring device and method based on visual alignment | |
| CN106525584A (en) | Preparation method for in-situ mechanic loading tool under transmission electron microscope | |
| CN110940582B (en) | Method for predicting fatigue strength of metal material through tensile test | |
| US20110032511A1 (en) | System and method to measure nano-scale stress and strain in materials | |
| CN114509339B (en) | Biax residual stress calibration device that impresss | |
| CN109211976A (en) | Semi-conductor silicon chip surface/sub-surface micro-cracks damage chirp beam splitting laser excitation infrared thermal wave detection device and method | |
| CN115266355A (en) | Method for determining specified value of elongation after fracture to be lower than 5% | |
| CN209342508U (en) | A kind of material strain original position EBSD observation test fixture | |
| CN108918257A (en) | A kind of stretching clamp for Al and Al superalloy sheet microspecimen | |
| CN110470441B (en) | Force application structure and method and application for measuring normal elastic constant of atomic force microscope probe based on force application structure | |
| JPH0194631A (en) | Wafer prober | |
| CN112924254B (en) | Transparent material natural crack preparation and tip position determination method and system | |
| CN208795678U (en) | A kind of sample clamping device for electron backscatter diffraction research in situ | |
| CN111141612A (en) | Device and method for testing hydrogen sulfide stress corrosion resistance of oil well pipe |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication |