CN103940910B - Nonlinear ultrasonic heat treatment process evaluation and optimization method and device - Google Patents

Nonlinear ultrasonic heat treatment process evaluation and optimization method and device Download PDF

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CN103940910B
CN103940910B CN201410205243.9A CN201410205243A CN103940910B CN 103940910 B CN103940910 B CN 103940910B CN 201410205243 A CN201410205243 A CN 201410205243A CN 103940910 B CN103940910 B CN 103940910B
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signal
heat treatment
nonlinear
ultrasonic
test specimen
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CN103940910A (en
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李卫彬
秦晓旭
胡诗诚
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Xiamen University
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Xiamen University
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object
    • G01N29/04—Analysing solids
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2291/00—Indexing codes associated with group G01N29/00
    • G01N2291/02—Indexing codes associated with the analysed material
    • G01N2291/023—Solids

Abstract

The invention discloses a nonlinear ultrasonic heat treatment process evaluation and optimization method and device. The method comprises the following steps: acquiring an ultrasonic baseband signal A1 propagated in a test piece and amplitude A2 of second harmonics, and calculating a nonlinear acoustic parameter beta' of the test piece, wherein the expression is as shown in the specification; and comparing the difference between nonlinear acoustic parameters of an untreated material and a material subjected to different heat treatment processes based on the obtained relative nonlinear acoustic parameter beta'. The better the heat treatment process is, the more uniform the interior structure of the material subjected to heat treatment is, the performance is greatly improved, and the acoustic nonlinear response of ultrasonic propagation is low. The microstructure of the material can be changed based on heat treatment, a direct correlation exists between the nonlinear response of ultrasonic propagation and the microstructure of the material. According to the method, the heat treatment process effects can be nondestructively, rapidly and effectively evaluated, and the related parameters of heat treatment process are optimized and perfected.

Description

The method and apparatus that non-linear ultrasonic assessment optimizes Technology for Heating Processing
Technical field
The present invention discloses the method and apparatus that the assessment of a kind of non-linear ultrasonic optimizes Technology for Heating Processing, by International Classification of Patents Table (IPC) divides and belongs to Material Testing Technology field, is specifically related to utilization and material property is carried out non-demolition assessment and sign Technology.
Background technology
Key project structural member material therefor, before formal input application, it usually needs improve it through Technology for Heating Processing Mechanical performance, meets the demand of engineering structure carrying.Why heat treatment can improve material property is primarily due to it and changes The microstructure (being i.e. parallel to homogenize sliding and the local plastic deformation restriction at interface) of material.Heat treatment process parameter is direct Affect the effect of Technology for Heating Processing, and then material property is had critical impact.Generally assess the side of Technology for Heating Processing effect Method is that the performance after destructive test material heat treatment changes, and this method is not only the longest, and waste is serious, process Complicated.And heat treatment process parameter is also to update in practice and perfect.How non-demolition, assess quickly and efficiently Technology for Heating Processing effect, optimizes, to improve heat treatment parameter extremely important.
Material microstructure and mechanical property directly affect the characteristic that sound is propagated in the material, ultrasonic evaluation and sign The change of materials microstructure and mechanical property is a kind of method being widely used.Conventional ultrasonic evaluation with detection method is By utilizing ultrasonic linear physical parameter (such as the velocity of sound, amplitude, attenuation quotient) sign materials microstructure and mechanical property, but mesh Front widely used linear ultrasonic appraisal procedure is insensitive to the microstructure change of material, is therefore being applied to Technology for Heating Processing Not reaching preferable effect during parameter optimization assessment, such as when several heat treatment parameter difference are less, linear ultrasonic method cannot By differentiation clear and definite for their quality.
Summary of the invention
For the deficiencies in the prior art, the invention provides the assessment of a kind of non-linear ultrasonic and optimize the side of Technology for Heating Processing Method, the method is obvious sound wave nonlinear response to be caused different based on changes in microstructure small in propagation medium, is A kind of Technology for Heating Processing recruitment evaluation based on non-linear ultrasonic method and optimisation technique.
It is a further object of the present invention to provide the assessment of a kind of non-linear ultrasonic and optimize the device of Technology for Heating Processing.
For reaching above-mentioned purpose, the present invention is achieved by the following technical solutions:
The method that the assessment of a kind of non-linear ultrasonic optimizes Technology for Heating Processing, fixes the test specimen through Technology for Heating Processing and leads The ultrasound wave entered and be suitable for frequency, obtains the fundamental frequency signal A of above-mentioned ultrasound wave respectively1Wave amplitude A with second harmonic2, calculate examination The relative nonlinear parameters,acoustic β ' of part, whereinValue β ' based on the relative nonlinear parameters,acoustic obtained, than Relatively untreated material and the difference of the nonlinear acoustics parameter through different heat treatment process, select nonlinear acoustics parameter minimum One group of test specimen, this group test specimen use process technique as optimized Technology for Heating Processing.
The method that the assessment of a kind of non-linear ultrasonic optimizes Technology for Heating Processing, its detecting step is as follows:
1) will fix through the test specimen of different heat treatment technique；
2) select the ultrasonic frequency being suitable for according to the material of test specimen, Signal generator produce ultrasonic signal；
3) by incentive probe, signal imported test portion, then received by receiving transducer and be back to receive unit；
4) receive the signal filtering that unit will receive, and signal is deposited on oscillograph after 100～2000 times average Storage；
5) by the signal of storage through Hanning window treatments, when selecting the most stable part to carry out-frequency conversion, have Effect obtains amplitude A 1 and signal amplitude A of double frequency the second harmonic of fundamental frequency guided wave2, calculateNumerical value；
6) relative nonlinear parameters,acoustic is calculated:
The value of nonlinear acoustics parameter beta is relevant to the wave amplitude of fundamental wave and the second harmonic, and its computing formula is
β = 8 A 2 A 1 2 k 2 x
Wherein A1And A2Being the amplitude of fundamental frequency wave-wave and the second harmonic respectively, k is wave number, and x is the distance that ripple is propagated；Test In have only to obtain relative nonlinear acoustics factor beta ', expression formula is as follows:
β ′ = A 2 A 1 2 ∝ β ;
7) value based on the relative nonlinear parameters,acoustic obtained, compares untreated material and through different heat treatment process The difference of nonlinear physical parameter, select minimum one group of nonlinear parameter as optimized Technology for Heating Processing.
Step 1) in, test specimen is fixed in fixture and carries out ultrasonic signal importing and reception.
Step 2) in Signal generator produce ultrasonic signal by attenuator to improve signal to noise ratio, then led by incentive probe Enter test specimen.
Step 3) in, for ensureing unified couple state, on incentive probe and receiving transducer, fixing device is to ensure to change It is stable that energy device contacts couple state with test specimen, and wherein receiving transducer receives ultrasonic signal and returns to reception after preamplifier amplifies In device.
Step 4) in, receive unit and the signal received is passed through power amplifier post filtering, utilize oscillograph to obtain and receive The signal waveform arrived, is inputted in computer；The data obtained by signal receiver input computer the most in the lump.
The assessment of a kind of non-linear ultrasonic optimizes the device of Technology for Heating Processing, including signal excitation/receptor, attenuator, swashs Encouraging probe, receiving transducer, preamplifier, oscillograph and computer, the excitation of signal excitation/receptor is suitable for certain frequency of test specimen Rate ultrasonic signal, through attenuator to improve signal to noise ratio and to connect incentive probe, ultrasonic signal is directed in test specimen, The other end of test specimen connects the acoustic signals that receiving transducer detection is propagated, and is filtered being sent to oscillograph after preamplifier In, oscillograph obtains the signal waveform received and is inputted in computer；The data also one obtained by signal excitation/receptor And input computer and carry out signal analysis.
Further, stationary fixture it is provided with between described incentive probe and receiving transducer with clamping through different heat treatment technique Test specimen.
The present invention provides a kind of for assessing thermal effectiveness, optimizes non-linear ultrasonic method and the dress of heat treatment parameter Put, utilize certain device to obtain fundamental frequency signal A1With second harmonic A2Wave amplitude, the relative nonlinear acoustics of test portion can be calculated Parameter beta ', effectively characterizes the relative change that material property occurs with β '.Test portion or test specimen after Technology for Heating Processing, material Interior microscopic organizational structure becomes uniform, and material property improves, and the nonlinear response of the ultrasound wave propagated wherein is decreased obviously, According to the power of nonlinear response, the quality of assessment Technology for Heating Processing, and then non-demolition assessment, optimization heat treatment process parameter.
Accompanying drawing explanation
Fig. 1 is that the present invention detects device schematic diagram.
Fig. 2 is the second harmonic and the relativity figure of fundamental wave in the test specimen after Technology for Heating Processing.
Detailed description of the invention
The invention will be further described below in conjunction with the accompanying drawings:
Embodiment: referring to Fig. 1 and Fig. 2, the assessment of a kind of non-linear ultrasonic optimizes the device of Technology for Heating Processing, including signal Excitation/receptor 1, attenuator 2, incentive probe 3, receiving transducer 4, preamplifier 5, oscillograph 6 and computer 7, signal swashs Encourage/receptor 1 excitation be suitable for test specimen certain frequency ultrasonic signal, through attenuator 2 to improve signal to noise ratio and to connect excitation Probe 3, ultrasonic signal is directed in test specimen M, and the other end at test specimen M connects the sound wave letter that receiving transducer 4 detection is propagated Number, it being filtered being sent in oscillograph 6 after preamplifier 5, oscillograph obtains the signal waveform received and is inputted In computer 7；The data obtained by signal excitation/receptor input computer 7 the most in the lump and carry out signal analysis.
The method that the assessment of a kind of non-linear ultrasonic optimizes Technology for Heating Processing, its detecting step:
1) will be fixed in fixture through the test specimen of different heat treatment technique；
2) select the ultrasonic frequency being suitable for according to the material of test specimen, Signal generator produce ultrasonic signal；
3) ultrasonic signal produced is passed through attenuator, to improve signal to noise ratio；
4) signal after overdamping, is imported test portion by incentive probe, then is received by receiving transducer, through preamplifier Return in receptor after amplification；
5) for ensureing unified couple state, on excitation transducer and reception transducer, fixing device is to ensure transducer Couple state is contacted stable with test specimen；
6) utilize oscillograph to obtain the signal waveform received, be inputted in computer；Obtained by signal receiver Data input computer the most in the lump；
7) receive unit by the signal that receives by power amplifier post filtering, and by signal on oscillograph through 100 ～2000 average rear storages；
8) by the signal of storage through Hanning window treatments, when selecting the most stable part to carry out-frequency conversion, have Effect obtains the amplitude A of fundamental frequency guided wave1Signal amplitude A with double frequency the second harmonic2, calculateNumerical value.
9) relative nonlinear parameters,acoustic is calculated；
The value of nonlinear acoustics parameter beta is relevant to the wave amplitude of fundamental wave and the second harmonic, and its computing formula is
β = 8 A 2 A 1 2 k 2 x
Wherein A1And A2Being the amplitude of fundamental frequency wave-wave and the second harmonic respectively, k is wave number, and x is the distance that ripple is propagated.Test In we have only to obtain relative nonlinear acoustics factor beta ', expression formula is as follows:
β ′ = A 2 A 1 2 ∝ β
10) value based on the relative nonlinear parameters,acoustic obtained, compares untreated material and through different heat treatment mistake The difference of the nonlinear physical parameter of journey, selects minimum one group of nonlinear parameter as optimized Technology for Heating Processing.
The principle of the invention:
The ultrasonic dielectric material uneven at heterogeneous microstructure is propagated, wave distortion can be caused, produce double frequency two Order harmonics.Heterogeneous microstructure the most uneven (microdefect increases), the amplitude of double frequency the second harmonic is the highest.Material is through overheated After processing technique, interior microscopic organizational structure can become relatively uniform, the corresponding ultrasound wave the second harmonic within it propagated Amplitude can reduce.According to measuring ultrasound wave the second harmonic and contrast of fundamental wave in the test specimen after different heat treatment technique Relation, can the uniformity of assessment material heterogeneous microstructure qualitatively, and then evaluate the change of material property, in Fig. 2, base Frequently signal amplitude A1, double frequency the second harmonic signal amplitude A2。
The present invention is a kind of to utilize the assessment of non-linear ultrasonic method, optimize the new technique of Technology for Heating Processing, and it utilizes non-broken Bad mode accurately assesses the change of the material property after different Technologies for Heating Processing, and then optimizes Technology for Heating Processing.This The bright microstructure that can change material based on heat treatment, and the microstructure of the nonlinear response of transonic and material has directly The relation connect.Process of thermal treatment is the best, and the material internal structure after Overheating Treatment is the most uniform, and what performance improved more arrives, and The acoustics nonlinear response of transonic is the least.Ultrasound non-linear by a set of Validity Test test specimen after Overheating Treatment The change of response, carries out nondestructive evaluation to material heat treatment effect.
The present invention can result in obvious sound wave nonlinear response not based on changes in microstructure small in propagation medium With, develop a kind of Technology for Heating Processing recruitment evaluation based on non-linear ultrasonic method and optimisation technique.This technology is to material After different heat treatment technique, the change of microstructure is very sensitive, can evaluate Technology for Heating Processing fast and effectively Quality, and then optimize heat treatment process parameter.
Described above, only utilize the embodiment of this origination techniques content, any those skilled in the art to use this wound Make modification, the change done, all belong to the scope of the claims that this creation is advocated, and be not limited to those disclosed embodiments.

Claims (4)

1. the method that a non-linear ultrasonic assessment optimizes Technology for Heating Processing, it is characterised in that: by the examination through Technology for Heating Processing The ultrasound wave of applicable frequency is fixed and imported to part, obtains the fundamental frequency signal A of above-mentioned ultrasound wave respectively1Wave amplitude A with second harmonic2, Calculate the relative nonlinear parameters,acoustic β ' of test specimen, wherein β '=A2/A1 2；Based on the relative nonlinear parameters,acoustic obtained Value β ', compares untreated material and the difference of the nonlinear acoustics parameter through different heat treatment process, selects nonlinear acoustics One group of test specimen that parameter is minimum, the process technique that this group test specimen uses is as optimized Technology for Heating Processing；Detecting step is as follows:
1) will fix through the test specimen of different heat treatment technique；
2) select the ultrasonic frequency being suitable for according to the material of test specimen, Signal generator produce ultrasonic signal and pass through attenuator To improve signal to noise ratio；
3) by incentive probe, signal imported test specimen, then received by receiving transducer and be back to receive unit；
4) receive unit by the signal that receives by power amplifier post filtering, and by signal on oscillograph through 100～ 2000 average rear storages；
5) by the signal of storage through Hanning window treatments, when selecting the most stable part to carry out-frequency conversion, effectively obtain Obtain the amplitude A of fundamental frequency guided wave1Signal amplitude A with double frequency the second harmonic2, calculate A2/A1 2Numerical value；
6) relative nonlinear parameters,acoustic is calculated:
The value of nonlinear acoustics parameter beta is relevant to the wave amplitude of fundamental wave and the second harmonic, and its computing formula is
β = 8 A 2 A 1 2 k 2 x
Wherein A1And A2Being the amplitude of fundamental wave and the second harmonic respectively, k is wave number, and x is the distance that ripple is propagated；Test only needs Obtaining relative nonlinear acoustics factor beta ', expression formula is as follows:
β ′ = A 2 A 1 2 ∝ β ;
7) value based on the relative nonlinear parameters,acoustic obtained, compares untreated material and non-through different heat treatment process The difference of linear physical parameter, selects minimum one group of nonlinear parameter as optimized Technology for Heating Processing.
The method that a kind of non-linear ultrasonic the most according to claim 1 assessment optimizes Technology for Heating Processing, it is characterised in that: step Rapid 1), in, test specimen is fixed in fixture and carries out ultrasonic signal importing and reception.
The method that a kind of non-linear ultrasonic the most according to claim 1 assessment optimizes Technology for Heating Processing, it is characterised in that: step Rapid 3) in, for ensureing unified couple state, on incentive probe and receiving transducer, fixing device is to ensure transducer and test specimen Contact couple state is stable, and wherein receiving transducer reception ultrasonic signal returns in receptor after preamplifier amplifies.
The method that a kind of non-linear ultrasonic the most according to claim 1 assessment optimizes Technology for Heating Processing, it is characterised in that: step Rapid 4), in, utilize oscillograph to obtain the signal waveform received, be inputted in computer；The data obtained by signal receiver Input computer the most in the lump.
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