Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

A method for non-destructive measurement of coating thickness by ultrasonic signal spectrum filtering technology

A filter technology and coating thickness technology, applied in the direction of using ultrasonic/sonic/infrasonic waves, measuring devices, instruments, etc., can solve problems such as time domain aliasing and difficult identification of spectral resonance frequencies

Active Publication Date: 2017-02-01
DALIAN UNIV OF TECH
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method is not affected by material properties and process environment, overcomes the problems of aliasing in the time domain and difficulty in identifying spectral resonance frequencies of conventional ultrasonic methods, and solves the problem of ultrasonic thickness measurement of double-layer coatings

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
  • A method for non-destructive measurement of coating thickness by ultrasonic signal spectrum filtering technology
  • A method for non-destructive measurement of coating thickness by ultrasonic signal spectrum filtering technology
  • A method for non-destructive measurement of coating thickness by ultrasonic signal spectrum filtering technology

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0036] The method of non-destructive measurement of coating thickness by ultrasonic signal spectrum filtering technology adopts Figure 4 The one shown includes sample table 1, double-coated sample 2, first coating thickness 0.25mm, second coating thickness 0.45mm, 5MHz ultrasonic probe 3, USIP40 ultrasonic flaw detector 4, DPO4032 digital oscilloscope 5 And the ultrasonic echo thickness measuring system that computer 6 forms. The specific implementation process of the thickness measurement of the double-layer coating sample is as follows:

[0037] (1) For a double-coated sample with a coating thickness ranging from 0.2 to 0.8 mm, select an ultrasonic probe 3 with a nominal frequency of 5 MHz, and first connect the measuring device to the system and calibrate the instrument. Gather the reflected sound pressure P (x) of this ultrasonic probe by DPO4032 digital oscilloscope 5, see Figure 5 . The cycle T=0.20μs of the signal is read by the computer 6, and the -6dB effective f...

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 for measuring thickness of coatings through the ultrasonic signal spectrum filter technology in a nondestructive mode, and belongs to the technical field of ultrasonic non-destructive testing. The method includes the steps that normalization processing is conducted on reflective sound pressure P[reflection] (x1) by ultrasonic incident sound pressure P[incidence] (x0), and then normalization sound pressure reflection coefficients R (x1-x0) of the coatings are acquired, and the R (x1-x0) is expanded to plural Fourier series through the spectrum analysis technology and divided into an independent real part function Real (f) and an independent imaginary part Imag (f); Fourier transformation is conducted on a real part function V[real] (f) in an effective frequency band acquired through windowing processing to acquire a power spectrum M (tau) of the real part function V real (f), FFT filtering bandwidths are selected according to the occurrence positions of maximum values of the power spectrum, the V[real] (f) is sequentially filtered to acquire a series of cosine functions, the periods of the cosine functions are read, propagation sound time ti of ultrasonic waves in the coatings is calculated, and then the thickness of the coatings is represented by the cooperation of longitudinal wave sound velocity of the coatings. The method is not affected by material attributes and the process environment, the problems that in a conventional ultrasonic method, aliasing occurs in time domains, and resonant frequency of the spectrum is difficult to recognize are solved, and the problem of ultrasonic thickness measurement of the multiple coatings is solved.

Description

technical field [0001] The invention relates to a method for non-destructively measuring coating thickness by ultrasonic signal spectrum filtering technology, which belongs to the technical field of ultrasonic non-destructive testing. Background technique [0002] Advanced coating technology is used in many fields of national defense and national economy such as national defense and military industry, machinery manufacturing, transportation, petrochemical industry, metallurgy and mining, electric power and energy. With people's continuous pursuit of high speed, high efficiency and high quality, the requirements for surface properties of materials are getting higher and higher, and higher requirements are put forward for coating materials and coating preparation processes, from the original single-layer coating technology to double-layer coating technology. The development of new technologies such as composite coatings and gradient functional composite coatings. The detectio...

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 Patents(China)
IPC IPC(8): G01B17/02
Inventor 雷明凯林莉马志远罗忠兵
Owner DALIAN UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com