传统的超声聚焦换能器大都采用单一的压电感测元件作为接收源，接收信号为作用于压电材料上的反射声场积分结果，无法反映反射声场的空间分布特性。采用激励与接收相分离的方式，研制一种新型阵列解析式超声聚焦换能器，利用多个感测元件为接收单元，通过一套基于FPGA技术的高速超声检测系统，实现了对被测试件反射声场的空间分布信号的采集和分析。阐述阵列解析式超声换能器的设计与制作方法，对换能器的多个感测元件的激励响应特性进行标定，利用该换能器的阵列感测元件的空间分布特性，对多角度声场感测信号进行分析和处理。以阶梯试件的台阶高度为测试对象开展空间感测声场测试方法分析试验研究，达到预期效果，为不规则裂缝缺陷检测奠定了基础。
宋国荣
,
秦登千
,
刘兴奇
,
吕炎
,
李永春
,
何存富
,
吴斌
. 阵列解析式超声聚焦换能器研制及空间感测分析方法研究[J]. 机械工程学报, 2016
, 52(2)
: 62
-69
.
DOI: 10.3901/JME.2016.02.062
The traditional ultrasonic focused transducers are always utilizing single piezoelectric sensor as receiver, and the received signal is the integral of the reflection of acoustic field at the piezoelectric material, but it can’t reflect the characteristics of reflected acoustic field. So that a new approach is presented which excitation and reception are separated to design and fabrication of array-analytic ultrasonic focused transducer. Using a multi-sensing element as receiver by a high-speed ultrasonic testing system based on FPGA technology to collected signals from different angles and analyzed these signals. Firstly, the approach of the design and manufacture of array-analytic ultrasonic focused transducer is expound and the multiple characteristics of excitation and response of the transducer array are calibrated. Secondly, the received multi-angle acoustic field signals are analyzed and processed by using the spatial distribution characteristics of the new type of transducer’s array sensing elements. Finally, the experimental research carries on the object of the different heights of the stairs sample by the approach of spatial-sensing acoustic field measure and the expected result has been achieved. That is build up a good basis for irregular crack defect detection.
[1] 宋国荣, 何存富, 魏晓玲, 等. 小试件材料弹性常数超声测量系统的研制[J]. 仪器仪表学报, 2006, 27(9)：1012-1015. SONG Guorong, HE Cunfu, WEI Xiaoling, et al. Development of an ultrasonic system to measure material elastic constants of small sample[J]. Chinese Journal of Scientific Instrument, 2006, 27(9)：1012-1015.
[2] 何存富, 吕炎, 宋国荣, 等. 线聚焦无镜头式PVDF超声探头的研制及V(f,z)分析法在表面波波速测量中的应用[J]. 机械工程学报, 2011, 47(21)：1-7. HE Cunfu, LÜ Yan, SONG Guorong, et al. Design, fabrication of line-focus lens-less PVDF transducers and applications on measuring surface acoustic waves with V(f,z) analytical method[J]. Journal of Mechanical Engineering, 2011, 47(21)：1-7.
[3] LOCKWOOD G R, TUMBULL D H, FOSTER F S. Fabrication of high frequency spherically shaped ceramic transducers[J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 1994, 41(2)： 231-235.
[4] TURNBULL D H, STARKOSKI B G , HARASIEWICZ K A, et al. Ultrasound backscatter microscope for skin imaging[C]// IEEE Ultrasonics Symposium, 1993： 985-988.
[5] BROWN J A, DEMORE C E M, LOCKWOOD G R. Design and fabrication of annular arrays for high-frequency ultrasound[J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 2004, 51(8)：1010-1017.
[6] MORTON C E, LOCKWOOD G R. Design of a 40 MHz annular array[C]// IEEE Ultrasound Symposium, 2001： 1135-1138.
[7] TALMAN J R, GARVERICK S L, LOCKWOOD G R. Integrated circuit for high-frequency ultrasound annular array[C]// Custom Integrated Circuits Conference, 2003： 477-480.
[8] GUST N, SCHELLHORN F. High frequency 16 channel ultrasonic microscope for annular arrays[C]// 2012 IEEE International Ultrasonics Symposium(IUS), 2012：1-3.
[9] FOSTER F S, PAVLIN C J, LOCKWOOD G R, et al. Principles and applications of ultrasound backscatter microscopy[J]. IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, 1993, 40(5)：608-617.
[10] 邱巨霖, 李永春, 钟政贤. PVDF解析式超音波换能器之制作、校正与特性量测[J]. 先进工程学刊, 2007, 2(4)：189-195. CHIU Chulin, LEE Yungchun, CHUNG Chenghsien. Fabrication and calibration of PVDF analytical ultrasound transducers[J]. Journal of Advanced Engineering, 2007, 2(4)：189-195.
