Torsion residual stress ultrasonic nondestructive test method

A residual stress, non-destructive testing technology, applied in the direction of measuring force, measuring device, instrument, etc.

Active Publication Date: 2016-03-23
BEIJING INSTITUTE OF TECHNOLOGYGY
View PDF5 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide an ultrasonic non-destructive testing method for torsional residual stress, which

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
  • Torsion residual stress ultrasonic nondestructive test method
  • Torsion residual stress ultrasonic nondestructive test method
  • Torsion residual stress ultrasonic nondestructive test method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0011] The specific embodiment of the present invention is described in detail below:

[0012] Torsional residual stress refers to the residual internal stress of transmission components such as shafts and cylinders during processing and service, which has an important impact on the life and safety of transmission components. Here, the drive shaft is taken as an example to detect the torsional residual stress in the 30° torsional direction.

[0013] 1. Shaft torsion residual stress detection principle

[0014] According to the theory of acoustoelasticity, when ultrasonic waves propagate in isotropic elastic media, when the polarization direction of wave particles is consistent with or opposite to the direction of residual stress, the change of ultrasonic wave velocity is linearly related to the change of residual stress. Therefore, the torsional residual stress of the shaft can be detected by ultrasonic critically refracted longitudinal waves.

[0015] σ ...

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 relates to a torsion residual stress ultrasonic nondestructive test method. Ultrasonic longitudinal waves form critical refraction longitudinal waves on a torsion surface of a shaft through waveform conversion once, time when the critical refraction longitudinal waves are spread in the shaft is tested, and corresponding torsion residual stress can be calculated through an acoustic elasticity theory. Through changing the frequency of the ultrasonic longitudinal waves, torsion residual stress at different depths on the same torsion surface can also be tested. The method provided by the invention can effectively solve the problem of distribution of the torsion residual stress on the torsion surface at different angles, helps to find a principle stress direction, can also perform fatigue strength analysis, is quite suitable for wide application in a production field and a maintenance repair field, is a novel method for detecting residual stress distribution through ultrasonic waves, and has quite bright application prospect.

Description

1. Technical field [0001] The invention relates to an ultrasonic non-destructive testing method for torsional residual stress. The method utilizes ultrasonic critical refraction longitudinal waves to detect the residual stress generated in different directions during the torsion process of a shaft member. 2. Background technology [0002] Torsional residual stress exists in transmission components such as cylindrical components and shaft components, and has an important impact on transmission strength. Transmission components are subjected to large stress random torsional loads during service, and are mostly fractured due to cracks, surface scratches and internal defects. This kind of fatigue fracture is an extremely common and serious failure mode. Torsional fracture belongs to low stress torsional fatigue fracture. According to the macroscopic and microscopic analysis of the fracture and the measured hardness distribution curve, the cause is generally due to the long-term ...

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): G01L1/25
CPCG01L1/255
Inventor 徐春广王俊峰李焕新白晓光田海兵宋剑锋吕卓肖定国潘勤学
Owner BEIJING INSTITUTE OF TECHNOLOGYGY
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