CN103926313A - Composite material porosity value evaluation method based on ultrasonic detection - Google Patents

Abstract

The invention belongs to the technical field of composite material and nondestructive detection, and relates to a composite material porosity value evaluation method based on ultrasonic detection. The method is implemented as follows: an ultrasonic transducer, an ultrasonic detection unit, porosity evaluation modeling, porosity database establishment and other main parts. Detection signals of a composite material test block with known porosity content are detected to obtain ultrasonic parameters for establishing a porosity evaluation model, and a porosity database is established according to the species and forming process of a composite material to be detected, wherein the adjacent porosity content difference range of the composite material test block for modeling is 0.5%-1%. By selection of a corresponding species and forming process in the composite material porosity database, porosity ultrasonic value evaluation of different composite materials can be realized, and auto alarm, recording, storing and the like of porosity values can be performed in real time. The composite material porosity value evaluation method can be used in interior and outdoor porosity value evaluation and detection of composite material engineering structures, does not require special sample preparation, and is high in efficiency and free of pollution.

Description

A kind of compound substance porosity Numerical evaluation method based on Ultrasonic Detection

Technical field

The invention belongs to compound substance and technical field of nondestructive testing, relate to a kind of compound substance porosity Numerical evaluation method based on Ultrasonic Detection.

Background technology

Along with compound substance applying in force structure, in composite structure design and structure manufacture process, need to compound substance porosity be detected and be assessed, prevent that the content of porosity from surpassing the secure threshold that design allows.At present, in composite material manufacturing process, mainly the porosity content that the compound substance porosity methods of sampling that adopts is indirectly inferred practice of composite part: concrete method is: (1) utilizes the sampling with stove part and sample preparation, then carry out metallographic observation, observe sample preparation section and whether have space, and whether the composite material parts of inferring same stove with this there is porosity; (2) utilize the corner surplus cutting from composite material parts to carry out sample preparation, then carry out metallographic observation, observe sample preparation section and whether have space, and infer with this whether composite material parts has porosity.Because compound substance is in manufacturing process, porosity has ferocious stochastic distribution feature, add the strong discreteness of compound substance self, in the most significant deficiency of these two kinds of methods be, all can not obtain the porosity distribution in practice of composite part, and be only a kind ofly based on theoretic technique, to be equal to and the strict hypothesis uniformly of processing quality, differ quite far away with actual conditions, and need special sample preparation, cycle is long, efficiency is low, has environmental pollution, is difficult to apply at present in the engineering structures such as compound substance, (3) utilize the end wave attenuation of ultrasound wave in compound substance to change, carry out the judge of compound substance porosity, the main method adopting is according to carrying out the rough judgement of porosity from ripple at the bottom of compound substance or the reduction that penetrates the transmitted wave amplitude of compound substance, its significant deficiency is, owing to affecting the many factors of end ripple or the variation of transmitted wave amplitude, and, many times, the reduction of end ripple or transmitted wave amplitude not necessarily because the existence of porosity cause, easily cause erroneous judgement, therefore, this method also could not be widely applied in actual applications.

Summary of the invention

The object of the invention is to propose a kind of ultrasonic Numerical evaluation method of non-destructive compound substance porosity of rapidly and efficiently environmental protection, realize the ultrasonic Numerical evaluation of porosity of compound substance, improve the accuracy of compound substance porosity assessment, to realize the ultrasonic Numerical evaluation of porosity of composite material engineering structure.Technical solution of the present invention is,

The basic comprising of the compound substance porosity Numerical evaluation method based on Ultrasonic Detection comprises: ultrasonic transducer (1), ultrasonic detecting unit (2), porosity assessment modeling (3), porosity data storehouse (4), ultrasonic transducer (1) adopts and is applicable to detected composite material component port surface contact coupling or noncontact coupling ultrasonic transducer, ultrasonic detecting unit (2) adopts has detection signal digitizing function and detection signal demonstration, detected parameters arranges, ultrasound parameter computational analysis and output, the Ultrasonic Detection instrument of memory function, the operational frequency bandwidth of the signal digitalized processing of ultrasonic detecting unit (2) is not less than 100MHz, utilize ultrasonic transducer (1) and ultrasound unit (2) to carry out ultrasound parameter test to the compound substance test block of known porosity content, obtain the ultrasound parameter of the differential compound substance test block of known same process feature and different porosities, utilize the ultrasound parameter of surveying to build compound substance porosity assessment mould, form the porosity assessment models of corresponding detected compound substance type, set up porosity data storehouse (4),

Compound substance porosity assessment modeling method for solving is:

(1) differential according to the compound substance test block process characteristic of known porosity content and porosity test block, determine the power side n of equation, n is generally not more than the compound substance test block number of known different porosities content, (2) solving equation:

$\begin{array}{c}{V}_{C1}=a_n{x}_{C1}^n+a_{n-1}{x}_{C1}^{n-1}+...+a_0\\ ...\\ V_{\mathrm{Cn}}=a_n{x}_{\mathrm{Cn}}^n+a_{n-1}{x}_{\mathrm{Cn}}^{n-1}+...+a_0\end{array}---\left(1\right)$

Here, a _n, a _n-1..., a ₀the porosity coefficient solving for needs,

V _c1..., V _cnbe respectively n the porosity content nominal value in known composite materials test block, refer to the contained porosity number of unit volume, with percentage form, represent,

by being surveyed ultrasound parameter in the compound substance porosity test block at the 1st known porosity content, the compound substance test block actual measurement gained ultrasound parameter by ultrasound unit (2) to the 1st known porosity content,

by being surveyed ultrasound parameter in the compound substance test block at n known porosity content, compound substance porosity test block actual measurement gained ultrasound parameter by ultrasound unit (2) to n known porosity content, by solving equation (1), calculate porosity coefficient a _n, a _n-1..., a ₀, be expressed in matrix as:

$\left[\begin{array}{c}{V}_{C1}\\ ...\\ V_{\mathrm{Cn}}\end{array}\right]=\left[\begin{array}{c}{a}_n\\ ...\\ a_0\end{array}\right]\×\left[\begin{array}{ccccc}{x}_{C1}^n& x_{C1}^{n-1}& ...& x_{C1}& 1\\ & & ...& & \\ x_{\mathrm{Cn}}^n& x_{\mathrm{Cn}}^{n-1}& ...& x_{\mathrm{Cn}}& 1\end{array}\right],---\left(2\right)$

,

$\left[\begin{array}{c}{a}_n\\ ...\\ a_0\end{array}\right]=\left[\begin{array}{c}{V}_{C1}\\ ...\\ V_{\mathrm{Cn}}\end{array}\right]\×{\left[\begin{array}{ccccc}{x}_{C1}^n& x_{C1}^{n-1}& ...& x_{C1}& 1\\ & & ...& & \\ x_{\mathrm{Cn}}^n& x_{\mathrm{Cn}}^{n-1}& ...& x_{\mathrm{Cn}}& 1\end{array}\right]}^{-1}---\left(3\right)$

Building compound substance porosity data storehouse method is:

(1) by material type, set up the 1st grade of search directory

here, m is compound substance material species number, is called for short " material ".

(2) by the technology type under every kind of catalog of materials, set up the 2nd grade of search directory

here, k is moulding process kind corresponding under material 1 catalogue, is called for short " technique ", and j is moulding process kind corresponding under material m catalogue.

(3) by the technology type under every kind of catalog of materials, set up 3rd level search directory,

here, for the porosity coefficient of the 1st kind of technique under material m, by formula (3), tried to achieve, just here in order to distinguish the porosity coefficient under different process, increased superscript 1, in like manner, for the porosity coefficient of the j kind technique under material m, by formula (3), tried to achieve, in order to distinguish the porosity coefficient under different process, increased superscript j here.

By ultrasonic detecting unit (2), according to set detected parameters, by measurement, from the boundary's wave energy in the detection signal of ultrasonic transducer (1), end wave energy, layer wave energy and travel-time, obtain ultrasound parameter.

For solving the compound substance porosity test block of compound substance porosity assessment modeling, by one group of compound substance test block that comprises different porosities content, formed, the differential scope of porosity content of adjacent compound substance test block is 0.5%-1.0%, and the compound substance test block number of different porosities content is got between 3-10 conventionally.

Solve the compound substance porosity assessment modeling that obtains and corresponding compound substance porosity data library storage in ultrasonic detecting unit (2), during detection, by selecting respective material and the technology type in compound substance porosity data storehouse, utilize ultrasonic transducer (1) and ultrasonic detecting unit (2) can realize the ultrasonic Numerical evaluation of porosity of different composite material.

The advantage that the present invention has and beneficial effect,

1. the porosity for composite material engineering structure detects, the present invention proposes a kind of ultrasonic Numerical evaluation method of nondestructive high-efficiency environment friendly compound substance porosity, utilize the compound substance porosity value assessment module of setting up, the porosity Numerical evaluation of compound substance total can be realized very easily, and automatic alarm, record, preservation of porosity numerical value etc. can be carried out in real time.Thereby composite material engineering structure provides very effective efficient porosity detection method fast;

2. the ultrasonic Numerical evaluation method of compound substance porosity of utilizing the present invention to propose, can to compound substance, carry out the ultrasonic Numerical evaluation of porosity by manual or autoscan mode, directly obtain the porosity numeric distribution of the actual structural area of compound substance, resulting testing result is directly reacted the porosity distribution in practice of composite part, and do not need special sample preparation, rapidly and efficiently, environmental nonpollution, is very easy to apply in the engineering structures such as compound substance;

3. the ultrasonic Numerical evaluation method of compound substance porosity of utilizing the present invention to propose, overcome and solely utilized while carrying out the rough judgement of porosity from the reduction of ripple at the bottom of compound substance or transmitted wave amplitude, what exist is many owing to affect the disturbing factor that end ripple or transmitted wave amplitude change, and easily causes that porosity is passed judgment on the problem such as to be forbidden;

4. the ultrasonic Numerical evaluation method of compound substance porosity of utilizing the present invention to propose, sets up the porosity data storehouse of different composite material and different composite forming materials, can carry out the porosity numerical analysis of composite material parts.

Accompanying drawing explanation

Fig. 1 is process step schematic diagram of the present invention;

Fig. 2 is porosity banking process schematic diagram of the present invention;

Fig. 3 is porosity Numerical evaluation schematic diagram of the present invention.

Embodiment

The basic comprising of the inventive method comprises: ultrasonic transducer 1, ultrasonic detecting unit 2, porosity assessment modeling 3, porosity are built storehouse 4, as shown in Figure 1, by 1 pair of composite material parts 5 of ultrasonic transducer, scan, in scanning process, by ultrasonic detecting unit 2, according to selection porosity assessment models, composite material parts 5 is carried out to real-time porosity Numerical evaluation, warning indication, result preservation and porosity numerical analysis etc.Ultrasonic transducer 1 adopts and is applicable to detected composite material component port surface contact coupling or noncontact coupling ultrasonic transducer, realize transmitting and receiving of ultrasound detection signal, the FJ series high-resolution ultrasound transducer that can select compound substance company limited of Air China to produce; Ultrasonic detecting unit 2 adopts the Ultrasonic Detection instrument of functions such as having detection signal digitizing function and detection signal demonstration, detected parameters (comprising thickness, the velocity of sound, gate etc.) setting, ultrasound parameter computational analysis and output, storage to form, the operational frequency bandwidth of its signal digitalized processing is 100MHz at least, can select MUT series high-resolution ultrasound detecting instrument, the CUS series high-resolution ultrasound autoscan checkout equipment that compound substance company limited of Air China produces directly to form ultrasonic detecting unit 2; Porosity assessment modeling 3 is for porosity, to build the new compound substance type of temporary transient vacancy in storehouse 4, utilize the compound substance test block of ultrasonic transducer 1 and 2 pairs of known porosity content of ultrasound unit to carry out after ultrasound parameter test, the compound substance porosity assessment modeling providing is solved, form the porosity assessment models of corresponding detected compound substance type; It is will be had with newly-established compound substance porosity value assessment module and be managed according to given selection principle by software programming that porosity is built storehouse 4, to select when carrying out the ultrasonic Numerical evaluation of compound substance porosity; Composite material parts 5 refers to the actual composite material parts that is required to carry out porosity Ultrasonic Detection.

Compound substance porosity is assessed modeling method for solving,

(1) differential according to detected compound substance material process characteristic and porosity test block, determine the power side n of equation, to carbon fiber resin matrix composite, the selection of n and the characteristic of detected compound substance and porosity assessment accuracy, porosity are differential etc. require relevant, n generally selects in 1-5, and n is generally not more than the compound substance test block number of known different porosities content.

(2) solving equation:

$\begin{array}{c}{V}_{C1}=a_n{x}_{C1}^n+a_{n-1}{x}_{C1}^{n-1}+...+a_0\\ ...\\ V_{\mathrm{Cn}}=a_n{x}_{\mathrm{Cn}}^n+a_{n-1}{x}_{\mathrm{Cn}}^{n-1}+...+a_0\end{array}---\left(1\right)$

Here, a _n, a _n-1..., a ₀the porosity coefficient solving for needs,

V _c1..., V _cnbe respectively the porosity content nominal value in the compound substance test block of n known porosity content, refer to the contained porosity number of unit volume, with percentage form, represent,

by being surveyed ultrasound parameter in the compound substance test block at the 1st known porosity content, compound substance porosity test block actual measured amount by 2 pairs of the 1st known porosity content of ultrasound unit obtains ultrasound parameter, according to after the running parameters such as the velocity of sound of setting, thickness, gate, gain, by 2 pairs of ultrasonic transducers 1 of ultrasound unit receive projectile energy from the detection signal in detected compound substance, return to energy, the travel-time carries out after computing, directly obtain ultrasound parameter

by being surveyed ultrasound parameter in the compound substance test block at n known porosity content, compound substance porosity test block actual measurement gained by ultrasound unit (2) to n known porosity content, can select the middle compound substance porosity test block of the Beijing Aviation manufacturing engineering ZL201220318356.6 of research institute and ZL201320020780.7, by ultrasound unit (2), directly export this ultrasound parameter

By solving equation (1), calculate porosity coefficient a _n, a _n-1..., a ₀, be expressed in matrix as:

$\left[\begin{array}{c}{V}_{C1}\\ ...\\ V_{\mathrm{Cn}}\end{array}\right]=\left[\begin{array}{c}{a}_n\\ ...\\ a_0\end{array}\right]\×\left[\begin{array}{ccccc}{x}_{C1}^n& x_{C1}^{n-1}& ...& x_{C1}& 1\\ & & ...& & \\ x_{\mathrm{Cn}}^n& x_{\mathrm{Cn}}^{n-1}& ...& x_{\mathrm{Cn}}& 1\end{array}\right],---\left(2\right)$

,

$\left[\begin{array}{c}{a}_n\\ ...\\ a_0\end{array}\right]=\left[\begin{array}{c}{V}_{C1}\\ ...\\ V_{\mathrm{Cn}}\end{array}\right]\×{\left[\begin{array}{ccccc}{x}_{C1}^n& x_{C1}^{n-1}& ...& x_{C1}& 1\\ & & ...& & \\ x_{\mathrm{Cn}}^n& x_{\mathrm{Cn}}^{n-1}& ...& x_{\mathrm{Cn}}& 1\end{array}\right]}^{-1}---\left(3\right)$

Compound substance porosity banking process is,

(1) by compound substance type, set up the 1st grade of search directory

here, m is material category number, is called for short " material ".

(2) by the moulding process type under every kind of catalog of materials, set up the 2nd grade of search directory

here, k is moulding process kind corresponding under material 1 catalogue, and j is moulding process kind corresponding under material m catalogue, is called for short " technique ".

(3) by the technology type under every kind of catalog of materials, set up 3rd level search directory, for example, for the j kind technique under material m catalogue, porosity banking process is:

here, for the porosity coefficient of the 1st kind of technique under material m, by formula (3), tried to achieve, just here in order to distinguish the porosity coefficient under different process, increased superscript 1, in like manner, for the porosity coefficient of the j kind technique under material m, by formula (3), tried to achieve, in order to distinguish the porosity coefficient under different process, increased superscript j here.

(4) porosity modeling process step is:

1. enter porosity MBM, determine whether new material, if belong to new material, the newly-built catalog of materials; Newly-built technique catalogue; In newly-built technique catalogue, preserve this porosity coefficient, form corresponding porosity assessment models;

If 2. do not belong to new material; Select the existing catalog of materials; Determine whether new technology; If genus new technology, newly-built technique catalogue; Under newly-built technique catalogue, preserve this porosity coefficient;

If 3. do not belong to new material; Do not belong to new technology yet; Enter selected technique catalogue under the selected catalog of materials; Under selected technique catalogue, preserve this porosity coefficient, form corresponding porosity assessment models, finish porosity and build storehouse, shown in Figure 2.

The ultrasonic Numerical evaluation method step of compound substance porosity is as follows,

(1) detect and prepare

1. determine porosity ultrasonic scan mode: when detected composite material parts is carried out to the manual scanning detection of porosity, the MUT series high-resolution ultrasound detecting instrument that ultrasound unit 2 can select compound substance material Ltd of Air China to produce; Connect ultrasound unit 2; When detected composite material parts is carried out to the detection of porosity automatic scanning, the CUS series high-resolution ultrasound autoscan checkout equipment that ultrasound unit 2 can select compound substance material Ltd of Air China to produce; Ultrasonic transducer 1 is connected with ultrasound unit 2; Enter the ultrasonic Numerical evaluation working interface of compound substance porosity.

(2) detecting step

As shown in Figure 3, the step of the ultrasonic Numerical evaluation of compound substance porosity is as follows:

Ultrasonic Detection running parameter (title of the velocity of sound, frequency of operation, thickness, gain, gate, detected composite material parts, detection date etc.) is 1. set;

2. porosity alarm threshold value V is set _t;

3. select porosity assessment models;

4. utilize zero porosity sample to carry out porosity check and correction;

5. enter porosity measurement working interface;

6. 1 pair of detected composite material parts 5 of mobile ultrasonic transducer carries out scanning;

7. by selecting porosity assessment models to calculate current detection point porosity numerical value V _ci;

8. porosity numerical value buffer memory, demonstration (data or image mode);

9. work as V _ci>V _ttime, the indication of reporting to the police;

10. whether complete detection, as detect completely, judge whether that result preserves;

if selection result is preserved, testing result is preserved under the working directory of setting automatically, and detection of end, enters porosity numerical analysis;

if selection result is not preserved, detection of end, enters porosity numerical analysis.

Claims (4)

1. the compound substance porosity Numerical evaluation method based on Ultrasonic Detection, is characterized in that,

The basic comprising of the compound substance porosity Numerical evaluation method based on Ultrasonic Detection comprises: ultrasonic transducer (1), ultrasonic detecting unit (2), porosity assessment modeling (3), porosity data storehouse (4), ultrasonic transducer (1) adopts and is applicable to detected composite material component port surface contact coupling or noncontact coupling ultrasonic transducer, ultrasonic detecting unit (2) adopts has detection signal digitizing function and detection signal demonstration, detected parameters arranges, ultrasound parameter computational analysis and output, the Ultrasonic Detection instrument of memory function, the operational frequency bandwidth of the signal digitalized processing of ultrasonic detecting unit (2) is not less than 100MHz, utilize ultrasonic transducer (1) and ultrasound unit (2) to carry out ultrasound parameter test to the compound substance test block of known porosity content, obtain the ultrasound parameter of the differential compound substance test block of known same process feature and different porosities, utilize the ultrasound parameter of surveying to build compound substance porosity assessment mould, form the porosity assessment models of corresponding detected compound substance type, set up porosity data storehouse (4),

Compound substance porosity assessment modeling method for solving is:

(1) differential according to the compound substance test block process characteristic of known porosity content and porosity test block, determine the power side n of equation, n is generally not more than the compound substance test block number of known different porosities content,

(2) solving equation:

$\begin{array}{c}{V}_{C1}=a_n{x}_{C1}^n+a_{n-1}{x}_{C1}^{n-1}+...+a_0\\ ...\\ V_{\mathrm{Cn}}=a_n{x}_{\mathrm{Cn}}^n+a_{n-1}{x}_{\mathrm{Cn}}^{n-1}+...+a_0\end{array}---\left(1\right)$

Here, a _n, a _n-1..., a ₀the porosity coefficient solving for needs,

V _c1..., V _cnbe respectively n the porosity content nominal value in known composite materials test block, refer to the contained porosity number of unit volume, with percentage form, represent, by surveyed ultrasound parameter in the 1st known composite materials porosity test block, the compound substance test block actual measurement gained ultrasound parameter by ultrasound unit (2) to the 1st known porosity content,

by being surveyed ultrasound parameter in the compound substance test block at n known porosity content, compound substance porosity test block actual measurement gained ultrasound parameter by ultrasound unit (2) to n known porosity content, by solving equation (1), calculate porosity coefficient a _n, a _n-1..., a ₀, be expressed in matrix as:

$\left[\begin{array}{c}{V}_{C1}\\ ...\\ V_{\mathrm{Cn}}\end{array}\right]=\left[\begin{array}{c}{a}_n\\ ...\\ a_0\end{array}\right]\×\left[\begin{array}{ccccc}{x}_{C1}^n& x_{C1}^{n-1}& ...& x_{C1}& 1\\ & & ...& & \\ x_{\mathrm{Cn}}^n& x_{\mathrm{Cn}}^{n-1}& ...& x_{\mathrm{Cn}}& 1\end{array}\right],---\left(2\right)$

,

$\left[\begin{array}{c}{a}_n\\ ...\\ a_0\end{array}\right]=\left[\begin{array}{c}{V}_{C1}\\ ...\\ V_{\mathrm{Cn}}\end{array}\right]\×{\left[\begin{array}{ccccc}{x}_{C1}^n& x_{C1}^{n-1}& ...& x_{C1}& 1\\ & & ...& & \\ x_{\mathrm{Cn}}^n& x_{\mathrm{Cn}}^{n-1}& ...& x_{\mathrm{Cn}}& 1\end{array}\right]}^{-1}---\left(3\right)$

Building compound substance porosity data storehouse method is:

(1) by compound substance type, set up the 1st grade of search directory

here, m is compound substance species number, is called for short " material ".

(2) by the moulding process type under every kind of catalog of materials, set up the 2nd grade of search directory

here, k is moulding process kind corresponding under material 1 catalogue, is called for short " technique ", and j is moulding process kind corresponding under material m catalogue.

(3) by the technology type under every kind of catalog of materials, set up 3rd level search directory,

here, for the porosity coefficient of the 1st kind of technique under material m, by formula (3), tried to achieve, just here in order to distinguish the porosity coefficient under different process, increased superscript 1, in like manner, for the porosity coefficient of the j kind technique under material m, by formula (3), tried to achieve, in order to distinguish the porosity coefficient under different process, increased superscript j here.

2. ultrasound parameter according to claim 1, it is characterized in that, ultrasonic detecting unit (2), according to set detected parameters, obtains ultrasound parameter by measurement from the boundary's wave energy in the detection signal of ultrasonic transducer (1), end wave energy, layer wave energy and travel-time.

3. the differential compound substance test block of different porosities in compound substance porosity assessment modeling method for solving according to claim 1, it is characterized in that, compound substance test block is comprised of one group of compound substance test block that comprises different porosities content, the differential scope of porosity content of adjacent compound substance test block is 0.5%-1.0%, and the compound substance test block number of different porosities content is got between 3-10 conventionally.

4. a kind of compound substance porosity Numerical evaluation method based on Ultrasonic Detection according to claim 1, it is characterized in that, solve the compound substance porosity assessment modeling that obtains and compound substance porosity data library storage in ultrasonic detecting unit (2), during detection, by selecting respective material and the technology type in compound substance porosity data storehouse, realize the ultrasonic Numerical evaluation of porosity of different composite material.