Method used for obtaining stress-strain curve of metal materials at static tensile states

A stress-strain curve, metal material technology, applied in the direction of analyzing materials, applying stable tension/pressure to test material strength, measuring devices, etc., can solve the problem of high cost of experiment time, inability to effectively simulate long-term force use, and inability to obtain Material tensile curve and other issues

Active Publication Date: 2019-01-01
TIANJIN PIPE GROUP CORP
View PDF9 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Before the present invention, metal material carries out tensile test, and test loading rate is generally maintained at 10 -5 the s -1 Above, it is impossible to effectively simulate the use of long-term stress, and the faster the tensile loading rate, the higher the material performance detected, and the greater the gap with the real material performance of the material under long-term stretching.
The relaxation test can measure the real stress of a single point, but it cannot obtain a complete material tensile curve, and the relaxation test takes a long time, and the cost of the test time is relatively high

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
  • Method used for obtaining stress-strain curve of metal materials at static tensile states
  • Method used for obtaining stress-strain curve of metal materials at static tensile states
  • Method used for obtaining stress-strain curve of metal materials at static tensile states

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0054] Such as Figure 4 is the true stress-strain curve of the tensile sample at a strain of 1.5%, using the formula σ 真实 = σ 最终 +a*exp(-t / b)+c*exp(-t / d) performs data fitting on the real stress-strain data obtained from the test, and the following results are obtained:

[0055] σ 最终 =461.76, a=-548.89, b=671.92, c=8653.88, d=671.81

[0056] σ 真实 =461.76-548.89*exp(-t / 671.92)+8653.88*exp(-t / 671.81)

[0057] Fitting curves such as Figure 4 As shown, according to the formula obtained from the fitting solution in the previous step, the time t is brought into infinity, and the obtained

[0058] σ s = σ 最终 =464.76MPa

Embodiment 2

[0060] Such as Figure 5 is the true stress-strain curve of the tensile sample at a strain of 3.5%, using the formula σ 真实 = σ 最终 +a*exp(-t / b)+c*exp(-t / d) performs data fitting on the real stress-strain data obtained from the test, and the following results are obtained:

[0061] σ 最终 =552.36, a=1.01e 5 , b=1015.81, c=8.92e 78 , d=51.91

[0062] σ 真实 =552.36+1.01e 5 *exp(-t / 1015.81)+8.92e 78 *exp(-t / 51.91)

[0063] Fitting curves such as Figure 4 As shown, according to the formula obtained from the fitting solution in the previous step, the time t is brought into infinity, and the obtained

[0064] σ s = σ 最终 =552.36MPa

Embodiment 3

[0066] Such as Image 6 is the true stress-strain curve of the tensile sample at 5.5% strain, using the formula σ 真实 = σ 最终 +a*exp(-t / b)+c*exp(-t / d) performs data fitting on the real stress-strain data obtained from the test, and the following results are obtained:

[0067] σ 最终 =618.91, a=1.75e 5 , b=1492.81, c=3.12e 29 , d=215.55

[0068] σ 真实 =651.98+1.75e 5 *exp(-t / 1492.81)+3.12e 29 *exp(-t / 215.55)

[0069] Fitting curves such as Figure 4 As shown, according to the formula obtained from the fitting solution in the previous step, the time t is brought into infinity, and the obtained

[0070] σ s = σ 最终 =618.91MPa

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

No PUM Login to view more

Abstract

The invention provides a method used for obtaining stress-strain curve of metal materials at static tensile states. The method is invented through improvement of tensile experiment and experiment dataprocessing analysis based on strain control or displacement control states, and mainly comprises two steps: firstly, experiment data is obtained through improved tensile experiment, and then the experiment data is adopted in processing of the real stress-strain curve of an obtained material at limit slow tensile, i.e. static tensile states. According to the method, the real stress-strain curve ofa material at long period stretching process is obtained through experiments, so that effective evaluation of material real using performance is realized, and important guiding meaning on the metal material at long term stretching states is achieved.

Description

technical field [0001] The invention relates to the field of performance detection of metal materials, and relates to a method for obtaining real stress-strain curves of metal materials under extreme slow stretching (static stretching) states and different temperature environments. Background technique [0002] Under the long-term tensile load service state of metal materials, especially in high-temperature environments, the structural failure will often be caused due to the reduction of material strength, resulting in huge economic losses. This method can effectively evaluate the performance attenuation of materials in this state . It has important guiding significance for the safe service of materials. [0003] Before the present invention, metal material carries out tensile test, and test loading rate is generally maintained at 10 -5 the s -1 Above, it is impossible to effectively simulate the use of long-term stress, and the faster the tensile loading rate is, the hig...

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
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N3/08
CPCG01N3/08G01N2203/0017
Inventor 黄永智孙宇史彬杨永昌谢冠男梅丽闫龙甄晓川吴永超黄进陈涛吕春莉骆敬辉郭强
Owner TIANJIN PIPE GROUP CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap