Method and device for on-line and damage-free detection for low density material defect by thermo-acoustic technology
A low-density material and thermoacoustic technology, applied in the generation of ultrasonic/sonic/infrasonic waves, and the use of sound waves/ultrasonic/infrasonic waves to analyze solids, etc., can solve problems such as difficult detection, lack, and difficult detection, and achieve low cost, Apply a wide range of effects
Inactive Publication Date: 2008-08-13
SOUTH CHINA NORMAL UNIVERSITY
View PDF0 Cites 6 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
But due to the lack of specialized means, this insulation material cannot be checked before the space shuttle launches
For example, the powdered foam material is almost completely transparent to x-rays and almost completely opaque to heat and ultrasound, making it difficult for traditional non-destructive testing methods to detect defects that may be buried below the surface
Due to the loose texture and good thermal insulation of the foam insulation layer, it is difficult to detect it by conventional non-destructive testing methods
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 moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0033] Embodiment 1 The preferred device of the present invention
[0034] figure 1 It is a schematic structural diagram of a preferred device of the present invention. The device of the present invention is composed of a microwave generating component, a rotating scanning component, an acoustic signal collecting component, and a computer. The microwave generating component is composed of the microwave generator 4-1 and the waveguide port 4-2; the rotating scanning component is controlled by the computer 2-4 through the digital I / O card to control the stepping motor and the driver 3-2 and the three-dimensional scanning platform 3-1 Move the acoustic detector 1-1 with the bracket 3-3; the acoustic signal acquisition component receives the signal from the acoustic detector 1-1, and the signal is coupled through the acoustic coupling agent 1-2, and then amplified by the signal amplifier 2-1 and filter 2- 2. The oscilloscope 2-3 collects and transmits to the computer 2-4, the contro...
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 |
|---|---|---|
| wavelength | aaaaa | aaaaa |
Login to View More
Abstract
The present invention provides a method for detecting defect of low density material in situ nondestructively by thermo acoustic technology which includes steps of: injecting impulse microwave to sample of material to be measured through waveguide outlet, inspiring material to be measured to produce thermo acoustic signal; receiving thermo acoustic signal equidirectionally in microwave generator by acoustic detectors without couplant pasted on surface of material; collecting and displaying data after the thermo acoustic signal magnified by signal amplifier to transmit and store in the computer; incepting omnidirectionally signals employing scan of stepping motor drove acoustic detectors controlled by computer; processing collected date to gain thermo acoustic image of sample. A device employed the said method comprising of microwave generating component, rotation scanning component, acoustic signal collecting component and computer component is also disclosed. The present invention overcomes the disadvantages of traditional technique which can't detecting low density material defect, has merits of nicety location, high resolving power. The device of present invention has low cost and is easy to popularize.
Description
Technical field [0001] The invention relates to a nondestructive test and measurement technology, in particular to a method and a device for nondestructively detecting defects in low-density materials by using thermoacoustic technology. Background technique [0002] Compared with traditional materials, the new low-density composite material has the characteristics of light weight, high strength and rigidity. Therefore, it is widely used in the aerospace industry. If in manufacturing or use, material defects will cause serious accidents. For example, scientists from NASA in the United States believe that the thermal insulation board of the outer fuel tank of the space shuttle, a foam material, due to its internal defects, will fall off during the takeoff of the space shuttle and hit and destroy the space shuttle body. This is likely to be The cause of the Columbia space shuttle crash. However, due to the lack of specialized means, this insulation material cannot be inspected befor...
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
Login to View More Patent Type & Authority Applications(China)
IPC IPC(8): G01N29/34G01N29/06
Inventor 邢达向良忠
Owner SOUTH CHINA NORMAL UNIVERSITY