Method for calculating twinning critical splitting stress by ebsd technique and Vickers hardness tester
What is Al technical title?
Al technical title is built by PatSnap Al team. It summarizes the technical point description of the patent document.
A technology of critical shear stress and Vickers hardness tester, which is applied in the direction of testing material hardness, analyzing materials, strength characteristics, etc., can solve the problems of high cost, low popularity, and inability to reflect the critical shear stress
Active Publication Date: 2021-12-21
INST OF METAL RESEARCH - CHINESE ACAD OF SCI
View PDF5 Cites 0 Cited by
Summary
Abstract
Description
Claims
Application Information
AI Technical Summary
This helps you quickly interpret patents by identifying the three key elements:
Problems solved by technology
Method used
Benefits of technology
Problems solved by technology
The value of the critical shear stress of twins simulated by the VPSC model cannot reflect the actual critical shear stress
Although experiments such as micro-cantilever beam compression can accurately measure the critical shear stress of twins, it requires high-end and expensive instruments to achieve, which is costly and not widely available.
Therefore, it is difficult to find an affordable and simple and convenient method to measure the actual critical shear stress of twins
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more
Image
Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
Click on the blue label to locate the original text in one second.
Reading with bidirectional positioning of images and text.
Smart Image
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0037] The method for calculating the critical shear stress of twins by EBSD technology and Vickers hardness tester comprises the following steps:
[0038] 1), EBSD sample preparation (to ensure the flatness of the sample):
[0039] First mount the sample on the sample mounting machine, and then pre-grind with 150#, 320#, 800#, 2000# water sandpaper in sequence. After removing deep scratches, perform vibration polishing on the automatic polishing machine. The polishing liquid is SiO 2 Nano-suspension solution, polished for about 1 hour, and finally a bright and trace-free polished surface with a mirror effect;
[0040] 2) Mark a certain position on the surface of the sample with Vickers hardness, and record the original morphology and crystal orientation of the area through metallographic microscope, scanning electron microscope and EBSD;
[0041] 3) Measure the hardness of the area with a Vickers hardness tester, change loads of different sizes (from 10-1000g), until twins ...
Embodiment 2
[0046] The method of calculating the critical shear stress of twins by EBSD technology and Vickers hardness tester, the critical shear stress of {11-21} twins is measured by the method described above for Zr-4 alloys in the quenched state in the β phase region .
[0047] The nominal composition of Zr-4 alloy is Zr-1.5Sn-0.2Fe-0.1Cr. This alloy has very low thermal neutron absorption cross section, high hardness, ductility and excellent corrosion resistance. It is mainly used in pressurized water reactors, Fuel cladding materials in boiling water reactors, heavy water reactors.
[0048] The first is the preparation of EBSD samples. EBSD samples are prepared after wire cutting samples, grinding and mechanical vibration polishing. Observe the shape change before and after the Vickers hardness indenter is pressed in through a metallographic microscope, such as image 3 shown. Keep under the load of 500g for 10 seconds, the hardness measured by Vickers hardness tester is 162HV, an...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more
PUM
Property
Measurement
Unit
hardness
aaaaa
aaaaa
Login to view more
Abstract
The method of calculating the critical splitting stress of twins by EBSD technology and Vickers hardness tester. This method mainly analyzes and calculates the Vickers hardness indentation geometry under different loads, and combines the functions of EBSD to calibrate the crystal orientation and twins, and finally obtains the critical shear stress of twins. The calculation process of this method is as follows: first prepare the EBSD block sample, and ensure the flatness of the sample surface by chemical wiping corrosion or mechanical vibration polishing; measure a certain area of the sample with a metallographic microscope and EBSD, and mark the position with Vickers hardness; then Test the hardness of this area through the Vickers hardness of different loads until under a certain load, twins appear next to the hardness indentation, and record the diagonal size and hardness value of the hardness indentation; then use EBSD to calibrate the twins Finally, the critical shear stress of the twin is obtained through the geometric analysis and calculation of the hardness indentation under this load combined with the calculation of the Schmid factor.
Description
technical field [0001] The invention belongs to the field of material analysis, and in particular provides a method for calculating the critical splitting stress of twins through EBSD technology and a Vickers hardness tester. Background technique [0002] Vickers hardness is to use a diamond pyramid indenter with an included angle of 136° to press into the outer surface of the sample under a specified load, keep the load for a certain period of time, and then remove the load, and obtain the indentation by measuring the length of the diagonal. Geometric relationship, calculate the surface area of the indentation, and then calculate the average pressure of the indentation surface area, which is the Vickers hardness value (HV) of the material. [0003] Under a certain load, the Vickers hardness indenter is pressed into the surface of the material, which means that the material is subjected to compressive stress, and the material will be deformed, and the two main ways of defo...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more
Application Information
Patent Timeline
Application Date:The date an application was filed.
Publication Date:The date a patent or application was officially published.
First Publication Date:The earliest publication date of a patent with the same application number.
Issue Date:Publication date of the patent grant document.
PCT Entry Date:The Entry date of PCT National Phase.
Estimated Expiry Date:The statutory expiry date of a patent right according to the Patent Law, and it is the longest term of protection that the patent right can achieve without the termination of the patent right due to other reasons(Term extension factor has been taken into account ).
Invalid Date:Actual expiry date is based on effective date or publication date of legal transaction data of invalid patent.
Login to view more