Unlock instant, AI-driven research and patent intelligence for your innovation.

Non-contact weak magnetism detection method for stress of crack initiation region

A magnetic detection, non-contact technology, applied in the direction of material magnetic variables, etc., can solve the problems of limited application, lack of systematic research in quantitative calculations, etc.

Active Publication Date: 2018-08-03
SHENYANG POLYTECHNIC UNIV
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

So far, metal magnetic memory detection technology has been developed to the point where non-contact detection is possible. At present, many experts in the world have devoted themselves to the research on the mechanism of magnetic memory signal generation, and have achieved certain results. There is a lack of systematic research on the quantitative calculation of non-contact detection based on the degree of force concentration, which limits the application of the magnetic memory method in the field of non-contact detection engineering technology in a weak magnetic environment

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
  • Non-contact weak magnetism detection method for stress of crack initiation region
  • Non-contact weak magnetism detection method for stress of crack initiation region
  • Non-contact weak magnetism detection method for stress of crack initiation region

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0142] The present invention comprises the following steps:

[0143] Step 1): Build a magnetic coupling model

[0144] When there is no external force, the magnetic induction of ferromagnetic materials is B 1 ,

[0145] mu 0 mu 1 =B 1 / H (1)

[0146] where μ 0 is the vacuum permeability, μ 1 is the relative permeability of the ferromagnetic material under no stress, and the external magnetic field intensity is H; when there is an external force, the magnetic induction intensity of the ferromagnetic material is B 2 , the energy increment of the ferromagnet under the action of external force is:

[0147]

[0148] Among them, W 1 , W 2 are the energy before and after the ferromagnetic material is subjected to external force, respectively.

[0149] When the ferromagnet is subjected to an external force, the crystal undergoes a corresponding phase transition, and the external stress increases the stress energy in the ferromagnetic crystal, resulting in a magnetoelasti...

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 non-contact weak magnetism detection method for stress of a crack initiation region and belongs to the technical field of a non-contact detection field of a stress concentration region of a ferromagnetic metal component, and in particular relates to the non-contact weak magnetism detection method for the stress of the crack initiation region. The invention provides the non-contact weak magnetism detection method for the stress of the crack initiation region. The non-contact weak magnetism detection method comprises the following steps: step 1): establishing a magnetomechanical coupling model; step 2): establishing a J-A stress magnetizing model; step 3) establishing a magnetic signal space scattering field model.

Description

technical field [0001] The invention belongs to the technical field of non-contact detection of stress concentration areas of ferromagnetic metal components, and in particular relates to a method for non-contact weak magnetic detection of stress in crack initiation areas. Background technique [0002] Large-scale ferromagnetic metal components will have different degrees of fatigue damage in the process of working in complex environments. During the operation of oil and gas pipelines, due to construction, corrosion, and external forces, stress damage will occur, resulting in defects such as deformation, corrosion, and cracks, resulting in pipeline failures. The situation is gradually deteriorating, which has planted a major security risk, posing a threat to national property and people's lives. [0003] As a new non-destructive testing method in the 21st century, the metal magnetic memory testing method is a practical and usable testing method for structural stress and defor...

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
IPC IPC(8): G01N27/85
CPCG01N27/85
Inventor 刘斌马泽宇王缔何璐瑶张贺任建
Owner SHENYANG POLYTECHNIC UNIV