CN102636249B - Method for measuring acoustic velocity of material by using surface wave - Google Patents

Method for measuring acoustic velocity of material by using surface wave Download PDF

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CN102636249B
CN102636249B CN 201210141763 CN201210141763A CN102636249B CN 102636249 B CN102636249 B CN 102636249B CN 201210141763 CN201210141763 CN 201210141763 CN 201210141763 A CN201210141763 A CN 201210141763A CN 102636249 B CN102636249 B CN 102636249B
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surface wave
ultrasonic
probe
sound velocity
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CN102636249A (en
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王强
张彦新
牛晓光
王庆
郝晓军
李中伟
赵纪峰
孙涛
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State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Hebei Electric Power Co Ltd
Hebei Electric Power Construction Adjustment Test Institute
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State Grid Corp of China SGCC
Electric Power Research Institute of State Grid Hebei Electric Power Co Ltd
Hebei Electric Power Construction Adjustment Test Institute
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Abstract

The invention relates to a method for measuring acoustic velocity of a material by using surface wave. According to the method, the same pair of ultrasonic surface wave probes are used for irradiating on and receiving from different materials in the same space, the transmission time of the ultrasonic surface wave in a standard test block with known acoustic velocity of ultrasonic surface wave and the transmission time of the ultrasonic surface wave in a work piece with unknown acoustic velocity of ultrasonic surface wave are respectively measured, and the acoustic velocity of the ultrasonic surface wave of the work piece material is calculated; and then, the acoustic velocity of the longitudinal ultrasonic wave and the acoustic velocity of the transverse ultrasonic wave are respectively calculated according to the relations of the transmission speed between the acoustic velocity of the longitudinal ultrasonic wave and the acoustic velocity of the ultrasonic surface wave as well as between the acoustic velocity of the transverse ultrasonic wave and the acoustic velocity of the ultrasonic surface wave. According to the method, the acoustic velocity of the work piece material can be measured without destructively sampling a measured work piece or measuring the thickness of the wall of the work piece, the measurement method is simple and practical, the measurement data are less, and the calculated quantity is relatively low.

Description

A kind of method of utilizing surface wave to measure the material velocity of sound
Technical field
The present invention relates to a kind of method of utilizing surface wave to measure the material velocity of sound.
Background technology
The material sonic velocity measurement method principle of standard code both at home and abroad all adopts from measured workpiece and cuts sample at present, accurately measures the thickness of sample TWith the travel-time of ultrasound wave in sample tAfter, according to relational expression
Figure 2012101417639100002DEST_PATH_IMAGE002
, calculate the velocity of sound V
The prerequisite that above-mentioned common method is carried out material sonic velocity measurement is to extract sample or to adopt mechanical means accurately to measure the thickness of test specimen from measured workpiece, but when engineering site is measured a certain workpiece material velocity of sound, often do not allow workpiece is carried out the destructiveness sampling, even record workpiece owing to reasons such as Workpiece structure can not adopt mechanical means, therefore can't adopt the above-mentioned conventional method measuring workpieces material velocity of sound.The patent No. is to have introduced the method for utilizing the incident respectively of different angles ultrasonic shear waves, reception in 200810054605.3, measure the travel-time of ultrasound wave in workpiece by secondary, calculate the workpiece material velocity of sound, can carry out material sonic velocity measurement to the workpiece of the unknown wall thickness of engineering site, the method has solved the difficult problem of engineering site material sonic velocity measurement.But calculated amount is bigger, and measurement data is more.
Summary of the invention
Technical matters to be solved by this invention provides a kind of employing digital ultrasonic flaw detector and utilizes surface wave to measure unknown wall thickness workpiece material velocity of sound new method.
The present invention adopts following technical scheme:
The present invention utilizes with a pair of ultrasonic surface wave probe with uniform distances respectively to the method for unlike material incident, reception, measure respectively ultrasonic surface wave in the reference block of the known ultrasonic surface wave velocity of sound travel-time and the travel-time in the unknown ultrasonic surface wave velocity of sound workpiece, calculate the ultrasonic surface wave velocity of sound of this workpiece material; Calculate the ultrasonic longitudinal wave velocity of sound and the ultrasonic shear waves velocity of sound with the velocity of propagation relational expression of the ultrasonic surface wave velocity of sound respectively according to the ultrasonic longitudinal wave velocity of sound, the ultrasonic shear waves velocity of sound again;
Its concrete grammar step is as follows:
(1) measures ultrasound wave at two overall transmission times that probe is inner t y :
Choose the identical first surface ripple probe (1) of parameters such as a pair of specification, forward position, time-delay and second surface ripple probe (2), first surface ripple probe (1) is popped one's head in (2) as receiving transducer as transmitting probe, second surface ripple, as shown in Figure 1, two probes are fitted tightly together, mobile mutually, make the echo wave amplitude the highest, can measure ultrasound wave at two overall transmission times that probe is inner t y , with this overall transmission time t y Divide equally tWith t Y2 , input to digital ultrasonic flaw detector respectively as the time-delay of described two surface wave probes.
(2) measure the travel-time of ultrasonic surface wave in the reference block of the known ultrasonic surface wave velocity of sound t 1 :
Choose described first surface ripple probe (1) and second surface ripple probe (2), with first surface ripple probe (1) as transmitting probe, second surface ripple probe (2) is as receiving transducer and be opposite to mutually with a constant spacing L on the surface of known ultrasonic surface wave reference block (3), records the travel-time of ultrasonic surface wave in described reference block (3) t 1 , following relational expression is then arranged:
L= C R1 × t 1 ； （1）
In the formula: C R1 : the ultrasonic surface wave velocity of sound in the reference block, unit: meter per second
L: the distance between two surface wave probes, unit: rice
t 1 : the travel-time of acoustic beam in reference block, unit: second
(3) measure the travel-time of ultrasonic surface wave in tested workpiece t 2 :
Choose described first surface ripple probe (1) and second surface ripple probe (2), first surface ripple probe (1) is opposite on the surface of tested workpiece (4) as receiving transducer and with a constant spacing L mutually as transmitting probe, second surface ripple probe (2), records the travel-time of ultrasonic surface wave in described workpiece (4) t 2 , following relational expression is then arranged:
L= C R2 × t 2 ； （2）
In the formula: C R2 : the ultrasonic surface wave velocity of sound in the tested workpiece, unit: meter per second is unknown number
L: the distance between two surface wave probes, unit: rice
t 2 : the travel-time of acoustic beam in workpiece, unit: second
Connection is separated above-mentioned formula (1) and (2), can draw the ultrasonic surface wave velocity of sound C R2
In above-mentioned formula (1), (2), the ultrasonic surface wave velocity of sound in the reference block C R1 Be known number; The ultrasonic surface wave velocity of sound in the tested workpiece C R2 Be unknown number; The travel-time of ultrasonic surface wave in reference block and workpiece t 1 , t 2 Record by ultra-sonic defect detector;
(4) at last according to the ultrasonic shear waves velocity of sound in the solid C S Respectively with the ultrasonic longitudinal wave velocity of sound C L , the ultrasonic surface wave velocity of sound C R Velocity of propagation relational expression (3) and (4) calculate the ultrasonic longitudinal wave velocity of sound C L With the ultrasonic shear waves velocity of sound C S :
Figure 2012101417639100002DEST_PATH_IMAGE004
（3）
（4）
In the formula:
Figure 2012101417639100002DEST_PATH_IMAGE008
Be the medium Poisson ratio.
The invention has the beneficial effects as follows: need not carry out destructiveness sampling and need not survey workpiece and can measure the workpiece material velocity of sound measured workpiece, measuring method be simple and practical, and measurement data is less, and calculated amount is less.
Description of drawings
Fig. 1 measures the ultrasound wave position view that the first surface ripple is popped one's head in and the second surface ripple is popped one's head in when the overall transmission time of two probe inside;
Fig. 2 is the synoptic diagram of measurement standard test block and tested workpiece.
In the accompanying drawings: 1 first surface ripple probe, 2 second surface ripples probe, 3 reference blocks, 4 tested workpiece.
Embodiment
Present embodiment concrete grammar step is as follows:
(1) measures ultrasound wave at two overall transmission times that probe is inner t y :
Choose the identical first surface ripple probe (1) of parameters such as a pair of specification, forward position, time-delay and second surface ripple probe (2), first surface ripple probe (1) is popped one's head in (2) as receiving transducer as transmitting probe, second surface ripple, as shown in Figure 1, two probes are fitted tightly together, mobile mutually, make the echo wave amplitude the highest, can measure ultrasound wave at two overall transmission times that probe is inner t y , with this overall transmission time t y Divide equally tWith t Y2 , input to digital ultrasonic flaw detector respectively as the time-delay of described two surface wave probes.
(2) measure the travel-time of ultrasonic surface wave in the reference block of the known ultrasonic surface wave velocity of sound t 1 :
Choose described first surface ripple probe (1) and second surface ripple probe (2), with first surface ripple probe (1) as transmitting probe, second surface ripple probe (2) is as receiving transducer and be opposite to mutually with a constant spacing L on the surface of known ultrasonic surface wave reference block (3), records the travel-time of ultrasonic surface wave in described reference block (3) t 1 , following relational expression is then arranged:
L= C R1 × t 1 ； （1）
In the formula: C R1 : the ultrasonic surface wave velocity of sound in the reference block, unit: meter per second
L: the distance between two surface wave probes, unit: rice
t 1 : the travel-time of acoustic beam in reference block, unit: second
(3) measure the travel-time of ultrasonic surface wave in tested workpiece t 2 :
Choose described first surface ripple probe (1) and second surface ripple probe (2), first surface ripple probe (1) is opposite on the surface of tested workpiece (4) as receiving transducer and with a constant spacing L mutually as transmitting probe, second surface ripple probe (2), records the travel-time of ultrasonic surface wave in described workpiece (4) t 2 , following relational expression is then arranged:
L= C R2 × t 2 ； （2）
In the formula: C R2 : the ultrasonic surface wave velocity of sound in the tested workpiece, unit: meter per second is unknown number
L: the distance between two surface wave probes, unit: rice
t 2 : the travel-time of acoustic beam in workpiece, unit: second
Connection is separated above-mentioned formula (1) and (2), can draw the ultrasonic surface wave velocity of sound C R2
In above-mentioned formula (1), (2), the ultrasonic surface wave velocity of sound in the reference block C R1 Be known number; The ultrasonic surface wave velocity of sound in the tested workpiece C R2 Be unknown number; The travel-time of ultrasonic surface wave in reference block and workpiece t 1 , t 2 Record by ultra-sonic defect detector;
(4) at last according to the ultrasonic shear waves velocity of sound in the solid C S Respectively with the ultrasonic longitudinal wave velocity of sound C L , the ultrasonic surface wave velocity of sound C R Velocity of propagation relational expression (3) and (4) calculate the ultrasonic longitudinal wave velocity of sound C L With the ultrasonic shear waves velocity of sound C S :
Figure 95928DEST_PATH_IMAGE004
（3）
（4）
In the formula:
Figure 231954DEST_PATH_IMAGE008
Be the medium Poisson ratio.

Claims (1)

1.一种利用表面波测量材料声速的方法，其特征在于用同一对超声表面波探头以相同间距分别对不同材质入射、接收的方法，分别测量超声表面波在已知超声表面波声速标准试块中的传播时间和未知超声表面波声速工件中的传播时间，计算出该工件材料的超声表面波声速；再根据超声纵波声速、超声横波声速分别与超声表面波声速的传播速度关系式算出超声纵波声速和超声横波声速；其具体方法步骤如下： 1. A method for utilizing surface waves to measure material velocity of sound is characterized in that the same pair of surface ultrasonic wave probes are used to incident and receive different materials with the same spacing, and to measure surface ultrasonic waves respectively in known ultrasonic surface wave sound velocity standard tests. Based on the propagation time in the block and the propagation time in the workpiece with unknown ultrasonic surface wave sound velocity, calculate the ultrasonic surface wave sound velocity of the workpiece material; then calculate the ultrasonic Longitudinal wave sound velocity and ultrasonic transverse wave sound velocity; Its specific method steps are as follows: （1）测量超声波在两个探头内部的总传输时间t y： (1) Measure the total transit time t y of ultrasonic waves inside the two probes: 选取一对规格、前沿、延时参数相同的第一表面波探头(1)和第二表面波探头(2)，将第一表面波探头(1)作为发射探头，第二表面波探头（2）作为接收探头，将两个探头紧密贴合在一起，相互移动，使回波波幅最高，测量出超声波在两个探头内部的总传输时间t y ，将此总传输时间t y 均分为t y！ 与t y2 ，作为所述两个表面波探头的延时分别输入至数字式超声波探伤仪；（2）测量超声表面波在已知超声表面波声速标准试块中的传播时间t 1 ： Select a pair of the first surface wave probe (1) and the second surface wave probe (2) with the same specifications, leading edge and delay parameters, use the first surface wave probe (1) as the transmitting probe, and the second surface wave probe (2) ) as a receiving probe, put the two probes closely together, and move each other to make the echo amplitude the highest, measure the total transmission time t y of the ultrasonic waves inside the two probes, and divide this total transmission time t y into t y! and t y2 , as the time delays of the two surface wave probes are respectively input to the digital ultrasonic flaw detector; (2) Measure the propagation time t 1 of the ultrasonic surface wave in the standard test block with known ultrasonic surface wave sound velocity: 选取所述第一表面波探头(1)和第二表面波探头(2)，将第一表面波探头(1)作为发射探头、第二表面波探头（2）作为接收探头并以一固定间距L相对置于已知超声表面波声速的标准试块（3）的表面上，测得超声表面波在所述标准试块（3）中的传播时间t 1 ，则有以下关系式： Select the first surface wave probe (1) and the second surface wave probe (2), use the first surface wave probe (1) as the transmitting probe, and the second surface wave probe (2) as the receiving probe, and use a fixed distance L is relatively placed on the surface of the standard test block (3) with known ultrasonic surface wave sound velocity, and the propagation time t 1 of the ultrasonic surface wave in the standard test block (3) is measured, then the following relationship is expressed: L=C R1 ×t 1 ；         （1） L = C R1 × t 1 ; (1) 式中：C R1 ：标准试块中超声表面波声速，单位：米/秒 In the formula: C R1 : ultrasonic surface wave sound velocity in the standard test block, unit: m/s    L：两表面波探头之间的距离，单位：米 L : distance between two surface wave probes, unit: meter    t 1 ：声束在标准试块中的传播时间，单位：秒 t 1 : propagation time of the sound beam in the standard test block, unit: second （3）测量超声表面波在被检工件中的传播时间t 2 ： (3) Measure the propagation time t 2 of the ultrasonic surface wave in the workpiece to be inspected: 选取所述第一表面波探头(1)和第二表面波探头(2)，将第一表面波探头(1)作为发射探头、第二表面波探头（2）作为接收探头并以一固定间距L相对置于被检工件（4）的表面上，测得超声表面波在所述工件（4）中的传播时间t 2 ，则有以下关系式： Select the first surface wave probe (1) and the second surface wave probe (2), use the first surface wave probe (1) as the transmitting probe, and the second surface wave probe (2) as the receiving probe, and use a fixed distance L is relatively placed on the surface of the workpiece (4) to be inspected, and the propagation time t 2 of the ultrasonic surface wave in the workpiece (4) is measured, then the following relationship is expressed: L=C R2 ×t 2 ；         （2） L = C R2 × t 2 ; (2) 式中：C R2 ：被检工件中超声表面波声速，单位：米/秒，为未知数 In the formula: C R2 : ultrasonic surface wave sound velocity in the inspected workpiece, unit: m/s, unknown    L：两表面波探头之间的距离，单位：米 L : distance between two surface wave probes, unit: meter    t 2 ：声束在工件中的传播时间，单位：秒 t 2 : propagation time of the sound beam in the workpiece, unit: second 联解上述公式（1）和（2），即可得出被检工件中超声表面波声速C R2 ； Combined solution of the above formulas (1) and (2), the ultrasonic surface wave sound velocity C R2 in the inspected workpiece can be obtained; 在上述公式（1）、（2）中，标准试块中超声表面波声速C R1 为已知数；被检工件中超声表面波声速C R2 为未知数；超声表面波在标准试块和工件中的传播时间t 1 、t 2 通过超声波探伤仪测得； In the above formulas (1) and (2), the sound velocity C R1 of the ultrasonic surface wave in the standard test block is a known number; the sound velocity C R2 of the ultrasonic surface wave in the tested workpiece is an unknown number; The propagation time t 1 and t 2 of is measured by ultrasonic flaw detector; （4）最后根据固体中超声横波声速C S 分别与超声纵波声速C L 、超声表面波声速C R 的传播速度关系式（3）和（4）计算超声纵波声速C L 和超声横波声速C S ： (4) Finally, calculate the ultrasonic longitudinal wave sound velocity C L and the ultrasonic transverse wave sound velocity C S according to the propagation velocity relational formulas (3) and (4) of the ultrasonic shear wave sound velocity C S in the solid and the ultrasonic longitudinal wave sound velocity C L and the ultrasonic surface wave sound velocity C R :
Figure 2012101417639100001DEST_PATH_IMAGE002
   （3）
Figure 2012101417639100001DEST_PATH_IMAGE002
(3)
Figure 2012101417639100001DEST_PATH_IMAGE004
 （4）
Figure 2012101417639100001DEST_PATH_IMAGE004
(4) 式中：σ为介质泊松比。 Where: σ is the Poisson's ratio of the medium.
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