针对工件内表面开口裂纹单面单侧定量检测困难的问题,采用相控阵超声绝对声时法(Absolute Arrival Time Technique,AATT)从单面单侧对不同厚度试块中的底面人工开口裂纹自身高度测量进行了数值仿真和实验,并对焊缝中的自然裂纹进行了AAT...针对工件内表面开口裂纹单面单侧定量检测困难的问题,采用相控阵超声绝对声时法(Absolute Arrival Time Technique,AATT)从单面单侧对不同厚度试块中的底面人工开口裂纹自身高度测量进行了数值仿真和实验,并对焊缝中的自然裂纹进行了AATT测量。对比AATT测量结果与常规衍射时差法超声检测(Time of Flight Diffraction,TOFD)测量结果并分析,发现AATT从单面单侧对底面开口裂纹进行定量测量可以达到与常规TOFD同样的测量精度。AATT操作简便,可单面单侧定量测量2 mm以上底面开口裂纹的自身高度。展开更多
The acoustic propagation characteristics of a finite one-dimensional water-glass phononic crystal(PC)are studied using the Schlieren visualization method,which is fast and non-invasive.The band structures of this PC a...The acoustic propagation characteristics of a finite one-dimensional water-glass phononic crystal(PC)are studied using the Schlieren visualization method,which is fast and non-invasive.The band structures of this PC are measured experimentally with continuous acoustic waves incident on it using the Schlieren method,and the results are highly consistent with the theoretical calculations.The dynamic acoustic field in the PC at different frequencies is imaged and the resonance phenomena in the components of the PC are observed.The results show that the Schlieren method is an effective means of studying the interactions between acoustic waves and PCs.展开更多
文摘针对工件内表面开口裂纹单面单侧定量检测困难的问题,采用相控阵超声绝对声时法(Absolute Arrival Time Technique,AATT)从单面单侧对不同厚度试块中的底面人工开口裂纹自身高度测量进行了数值仿真和实验,并对焊缝中的自然裂纹进行了AATT测量。对比AATT测量结果与常规衍射时差法超声检测(Time of Flight Diffraction,TOFD)测量结果并分析,发现AATT从单面单侧对底面开口裂纹进行定量测量可以达到与常规TOFD同样的测量精度。AATT操作简便,可单面单侧定量测量2 mm以上底面开口裂纹的自身高度。
基金Supported by the National Natural Science Foundation of China under Grant Nos 10974145,10804050 and 10834009.
文摘The acoustic propagation characteristics of a finite one-dimensional water-glass phononic crystal(PC)are studied using the Schlieren visualization method,which is fast and non-invasive.The band structures of this PC are measured experimentally with continuous acoustic waves incident on it using the Schlieren method,and the results are highly consistent with the theoretical calculations.The dynamic acoustic field in the PC at different frequencies is imaged and the resonance phenomena in the components of the PC are observed.The results show that the Schlieren method is an effective means of studying the interactions between acoustic waves and PCs.