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A Novel On-Site-Real-Time Method for Identifying Characteristic Parameters Using Ultrasonic Echo Groups and Neural Network
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作者 Shuyong Duan Jialin Zhang +2 位作者 Heng Ouyang Xu Han Guirong Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期215-228,共14页
On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness... On-site and real-time non-destructive measurement of elastic constants for materials of a component in a in-service structure is a challenge due to structural complexities,such as ambiguous boundary,variable thickness,nonuniform material properties.This work develops for the first time a method that uses ultrasound echo groups and artificial neural network(ANN)for reliable on-site real-time identification of material parameters.The use of echo groups allows the use of lower frequencies,and hence more accommodative to structural complexity.To train the ANNs,a numerical model is established that is capable of computing the waveform of ultrasonic echo groups for any given set of material properties of a given structure.The waveform of an ultrasonic echo groups at an interest location on the surface the structure with material parameters varying in a predefined range are then computed using the numerical model.This results in a set of dataset for training the ANN model.Once the ANN is trained,the material parameters can be identified simultaneously using the actual measured echo waveform as input to the ANN.Intensive tests have been conducted both numerically and experimentally to evaluate the effectiveness and accuracy of the currently proposed method.The results show that the maximum identification error of numerical example is less than 2%,and the maximum identification error of experimental test is less than 7%.Compared with currently prevailing methods and equipment,the proposefy the density and thickness,in addition to the elastic constants.Moreover,the reliability and accuracy of inverse prediction is significantly improved.Thus,it has broad applications and enables real-time field measurements,which has not been fulfilled by any other available methods or equipment. 展开更多
关键词 Parameter identification ultrasonic echo group High-precision modeling Artificial neural network NDT
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Evaluation of thermal sprayed coating using ultrasonic inspection by means of bottom echo back reflection 被引量:1
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作者 Toshifumi KUBOHORI Toru ITO +2 位作者 Wahidul lah WAHI Yasuyuki INUI Toshiro IKUTA 《中国有色金属学会会刊:英文版》 EI CSCD 2009年第4期984-987,共4页
Thermal spraying technique is widely used in various mechanical parts as a surface reforming technique.However,as demand to maintain superior mechanical performance in harsh operating environment increases,the need fo... Thermal spraying technique is widely used in various mechanical parts as a surface reforming technique.However,as demand to maintain superior mechanical performance in harsh operating environment increases,the need for non-destructive evaluation method for thermal spray coating becomes more important.For this purpose,we thinned the thickness of the thermal sprayed coating by abrasion with blasting and used ultrasonic inspection by means of bottom echo reflection for effective measurement of abrasion quantity in thermal sprayed coating.The results obtained are summarized as follows.When the thickness of thermal sprayed coating becomes thin,the echo height increases.This is because thermal sprayed coatings absorb ultrasonic energy.Ultrasonic energy absorbed by Al2O3 is smaller compared with Fe-13Cr coating.Thermal sprayed coatings submerged in water have a lower echo height compared with air.As mentioned above,the thermal sprayed coating thickness can be estimated using ultrasonic inspection by means of bottom echo back reflection. 展开更多
关键词 超声波检测 热喷涂层 评价方法 声反射 底部 热喷涂涂层 涂层厚度 能量吸收
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Ultrasonic echo denoising in liquid density measurement based on improved variational mode decomposition
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作者 WANG Xiao-peng ZHAO Jun ZHU Tian-liang 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第4期326-334,共9页
The ultrasonic echo in liquid density measurement often suffers noise,which makes it difficult to obtain the useful echo waveform,resulting in low accuracy of density measurement.A denoising method based on improved v... The ultrasonic echo in liquid density measurement often suffers noise,which makes it difficult to obtain the useful echo waveform,resulting in low accuracy of density measurement.A denoising method based on improved variational mode decomposition(VMD)for noise echo signals is proposed.The number of decomposition layers of the traditional VMD is hard to determine,therefore,the center frequency similarity factor is firstly constructed and used as the judgment criterion to select the number of VMD decomposition layers adaptively;Secondly,VMD algorithm is used to decompose the echo signal into several modal components with a single modal component,and the useful echo components are extracted based on the features of the ultrasonic emission signal;Finally,the liquid density is calculated by extracting the amplitude and time of the echo from the modal components.The simulation results show that using the improved VMD to decompose the echo signal not only can improve the signal-to-noise ratio of the echo signal to 20.64 dB,but also can accurately obtain the echo information such as time and amplitude.Compared with the ensemble empirical mode decomposition(EEMD),this method effectively suppresses the modal aliasing,keeps the details of the signal to the maximum extent while suppressing noise,and improves the accuracy of the liquid density measurement.The density measurement accuracy can reach 0.21%of full scale. 展开更多
关键词 liquid density measurement ultrasonic echo signal variational mode decomposition(VMD) signal denoising signal-to-noise ratio
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Main Features of a Complete Ultrasonic Measurement Model: Formal Aspects of Modeling of Both Transducers Radiation and Ultrasonic Flaws Responses 被引量:1
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作者 Michel Darmon Sylvain Chatillon 《Open Journal of Acoustics》 2013年第3期43-53,共11页
This paper aims at describing the theoretical fundamentals of a reciprocity-based ultrasonic measurement model. This complete inspection simulation can be decomposed in two modeling steps, one dedicated to transducer ... This paper aims at describing the theoretical fundamentals of a reciprocity-based ultrasonic measurement model. This complete inspection simulation can be decomposed in two modeling steps, one dedicated to transducer radiation and one to flaw scattering and echo synthesis. The physical meaning of the input/output signals used in these two modeling tools is defined and the theoretical principles of both field calculation and echo computation models are then detailed. The influence on the modeling results of some changes in the simulated configuration (as the incident angle) or some input signal parameters (like the frequency) are studied: it is thus theoretically established that the simulated results can be compared between each other in terms of amplitude for numerous applications when changing some inspection parameters in the simulation but that a calibration for echo calculation is generally required. 展开更多
关键词 ultrasonic Modeling TRANSDUCER RADIATION Defects echoES Calibration
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Ultrasonic Investigation of Elastic Anomalies in Lithium Sodium Sulphate Hexahydrate Single Crystal
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作者 George Varughese Santhosh Kumar 《Open Journal of Acoustics》 2014年第3期131-137,共7页
An extensive study of the thermal properties of Lithium Sodium Sulphate Hexa hydrate (LSSW) single crystal, with Trigonal structure, has been carried out using ultrasonic Pulse Echo Overlap (PEO) technique, Differenti... An extensive study of the thermal properties of Lithium Sodium Sulphate Hexa hydrate (LSSW) single crystal, with Trigonal structure, has been carried out using ultrasonic Pulse Echo Overlap (PEO) technique, Differential Thermal Analysis (DTA) and Thermo Gravimetric Analysis (TGA). The temperature variation of elastic constants of LiNa3(SO4)2·6H2O single crystal have been reported for the first time. The second order elastic stiffness constants C11,?C33, C44, along the various directions in the crystal have been determined in the temperature range 300 - 330 K. The change in velocity with temperature with respect to the room temperature value has been measured using PEO technique. Significant anomalies were observed in C11?and C33?at 316 K. The elastic constant C12?has shown no variation in the temperature range 300 - 319 K. A minor deviation for C44?at 305 K following a parabolic change has been observed. The minor anomalies observed in the elastic constants of LSSW may be due to its dehydration of water of crystallization in the range 304 - 319 K. DTA studies showed an appreciable endothermic change in the range 309 K-369.79 K. TGA curve exhibited a decrease in weight of 1.687 mg in the temperature range 304 K-360 K. The minor anomalies observed in the elastic constants of LSSW may be due to loosing of its water of crystallization in the range 309 - 319 K. On loosing water there will not be any change in chemical structure but there will be physical change associated with loosing of water molecule. 展开更多
关键词 ultrasonicS Single Crystal ELASTIC Properties Pulse echo OVERLAP Technique
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Optimization of ultrasonic elastography by coded excitation and transmit-side multi-frequency compounding
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作者 张志宏 刘昊霖 +1 位作者 何颖妮 刘东权 《Journal of Central South University》 SCIE EI CAS 2014年第3期1003-1010,共8页
To improve the quality of ultrasonic elastography, by taking the advantage of code excitation and frequency compounding, a transmitting-side multi-frequency with coded excitation for elastography (TFCCE) was propose... To improve the quality of ultrasonic elastography, by taking the advantage of code excitation and frequency compounding, a transmitting-side multi-frequency with coded excitation for elastography (TFCCE) was proposed. TFCCE adopts the chirp signal excitation scheme and strikes a balance in the selection of sub-signal bandwidth, the bandwidth overlap and the number of sub-strain image based on theoretical derivation, so as to further improve the quality of elastic image. Experiments have proved that, compared with the other optimizing methods, the elastographyic signal-to-noise ratio(Re-SN) and contrast-to-noise ratio(Re-CN) are improved significantly with different echo signal-to-noise ratios (ReSN) and attenuation coefficients. When ReSN is 50 dB, compared with short pulse, Rc-SN and Re-CN obtained by TFCCE increase by 53% and 143%, respectively. Moreover, in a deeper investigation (85-95 mm), the image has lower strain noise and clear details. When the attenuation coefficient is in the range of 0-1 dB/(cm.MHz), Re-SN and Re-CN obtained by TFCCE can be kept in moderate ranges of 5〈Re-SN〈6.8 and 11.4〈Re-CN〈15.2, respectively. In particular, for higher tissue attenuation, the basic image quality cannot be ensured with short pulse excitation, while mediocre quality strain figure can be obtained by TFCCE. Therefore, the TFCCE technology can effectively improve the elastography quality and can be applied to ultrasonic clinical trials. 展开更多
关键词 ultrasonic elastography coded excitation transmit-side multi-frequency compounding elastographyic signal-to-noise ratio echo signal-to-noise ratio contrast-to-noise ratio
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Wavelet packet energy analysis of laser ultrasonic
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作者 Chao Sorlg Bin Zheng +2 位作者 Hualing Guo Hui Liu Jing Hou 《光电工程》 CAS CSCD 北大核心 2017年第6期648-658,共11页
关键词 飞机 发动机 叶片 焊接部位
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ULTRASONIC BEHAVIOR OF EPOXY RESINS/POLY (ETHYLENE OXIDE) BLENDS CURED WITH PHTHALIC ANHYDRIDE
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作者 郑思珣 王海千 +4 位作者 罗筱烈 张乃斌 马德柱 朱长飞 胡建恺 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1995年第1期20-27,共8页
By means of ultrasonic attenuation apparatus, the ultrasonic velocity and attenuation ofanhydride-cured epoxy resins (EP)/poly (ethylene oxide) (PEO) blends were measured on thebasis of pulse-echo method. It was found... By means of ultrasonic attenuation apparatus, the ultrasonic velocity and attenuation ofanhydride-cured epoxy resins (EP)/poly (ethylene oxide) (PEO) blends were measured on thebasis of pulse-echo method. It was found that the sonic velocity of the blends decreased as thetemperature increased, but attenuation coefficient increased and possessed a peak value. Largervelocity and smaller attenuation coefficient(α)can be obtained from perfect crosslinking networkstructures of pure DGEBA cured with phthalic anhydride(PA). As for cured DGEBA/PEO blendsystems,sonic velocity decreased as a function of PEO concentration,but attenuation coefficient(α) increased. 展开更多
关键词 Pulse-echo method ultrasonic velocity Attenuation coefficient (α) Epoxy resins /poly (ethylene oxide)blends Crosslinking network
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高性能井筒超声脉冲回波扫描成像测井仪研制
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作者 沈友爱 陶爱华 +3 位作者 刘汇鑫 李亨 王文梁 孙志峰 《应用声学》 CSCD 北大核心 2024年第6期1350-1359,共10页
多功能超声成像测井仪采用超声脉冲反射法对套管腐蚀及固井质量做定量评价。利用从井眼内壁反射波形提取的幅度及到时实现井眼内壁高分辨率成像;提取套管共振波的共振频率计算套管厚度;采用全波反演方法反演套管后环空介质的声阻抗。通... 多功能超声成像测井仪采用超声脉冲反射法对套管腐蚀及固井质量做定量评价。利用从井眼内壁反射波形提取的幅度及到时实现井眼内壁高分辨率成像;提取套管共振波的共振频率计算套管厚度;采用全波反演方法反演套管后环空介质的声阻抗。通过优化采集模式、研制高性能换能器并建立固井质量评价模版确保仪器性能优于同类产品。现场实测资料表明,仪器可准确测量套管壁厚,识别射孔层段和射孔孔眼,识别套损缺陷,为套管找漏及侧钻点选择提供重要的决策依据,并准确评价双层套管情况下的内层套管固井质量,同时还可以在裸眼井中获取井壁表面裂缝、层理、孔洞等地质构造信息。 展开更多
关键词 超声波反射法 内壁成像 套损评价 水泥胶结
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铝面板泡沫夹芯结构材料脱粘缺陷的超声脉冲多次反射法检测
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作者 肖轲迪 吴君豪 +2 位作者 罗明 支凡 张颖 《宇航材料工艺》 CAS CSCD 北大核心 2024年第3期77-82,共6页
针对铝面板泡沫夹芯结构材料脱粘缺陷的检测问题,开展了超声脉冲多次反射法检测技术研究。分析了超声脉冲多次反射法的检测原理,制作了人工模拟缺陷试样,进行了自动检测C扫描成像,通过灰度点数量统计方法分析和优化了缺陷识别的结果。... 针对铝面板泡沫夹芯结构材料脱粘缺陷的检测问题,开展了超声脉冲多次反射法检测技术研究。分析了超声脉冲多次反射法的检测原理,制作了人工模拟缺陷试样,进行了自动检测C扫描成像,通过灰度点数量统计方法分析和优化了缺陷识别的结果。研究结果表明,超声脉冲多次反射法能有效检出铝面板泡沫夹芯结构材料中的脱粘缺陷,为材料研制和质量评估提供依据。 展开更多
关键词 超声脉冲多次反射法 铝面板泡沫夹芯结构材料 脱粘缺陷 C扫描成像
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基于容器内壁反射能量变化的液位超声检测方法
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作者 张跳跳 贺西平 刘昱 《振动与冲击》 EI CSCD 北大核心 2024年第8期257-262,共6页
置于液罐外壁液面高度附近处的收发探头发射声束透过罐壁在其内壁产生一投影面积,提出利用液体在该投影面积中的占比与能量之间的关系来检测液位的变化。计算探头接收到的回波信号能量,该能量值与液面高度成反比,由此定征液面位置。搭... 置于液罐外壁液面高度附近处的收发探头发射声束透过罐壁在其内壁产生一投影面积,提出利用液体在该投影面积中的占比与能量之间的关系来检测液位的变化。计算探头接收到的回波信号能量,该能量值与液面高度成反比,由此定征液面位置。搭建试验系统,采集回波信号,将算得的接收能量值代入占比面积表达式得到相对探头的液面位置。计算的液面位置与实际液面位置相吻合,两者的误差仅小于2.465 mm。有限元仿真计算也验证了探头接收能量与液位变化的关系。 展开更多
关键词 超声波 液位检测 回波能量
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基于超声时频分析与残差网络的生物组织变性识别
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作者 刘备 许克晖 +2 位作者 杨德智 彭梓齐 杨江河 《传感器与微系统》 CSCD 北大核心 2024年第1期40-43,共4页
为了能对高强度聚焦超声(HIFU)治疗过程中的生物组织进行实时准确的变性识别,提出了一种基于超声时频分析与残差网络(ResNet)的生物组织变性识别方法。首先,采用广义S变换(GST)方法对生物组织超声回波信号进行时频分析,得到二维时频图;... 为了能对高强度聚焦超声(HIFU)治疗过程中的生物组织进行实时准确的变性识别,提出了一种基于超声时频分析与残差网络(ResNet)的生物组织变性识别方法。首先,采用广义S变换(GST)方法对生物组织超声回波信号进行时频分析,得到二维时频图;然后,通过迁移学习,将在ImageNet数据集上训练得到的参数应用于超声回波信号数据集;最后,利用ResNet101模型从生物组织变性前后的时频图中学习和提取有效的变性信息,并可视化变性特征轨迹,实时地完成生物组织变性识别。实验结果表明:相较于现有基于信号能量,AR系数以及熵特征的变性识别方法,GST-ResNet方法无需人为经验选取特征参数,具有更高的识别率,可以实时准确地完成生物组织的变性识别。 展开更多
关键词 时频分析 残差网络 高强度聚焦超声 超声回波信号 变性识别
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奥氏体不锈钢材料劣化快速评价技术
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作者 陈仙凤 周彬 +4 位作者 余焕伟 肖飚 任绪凯 杜锡勇 唐艳同 《理化检验(物理分册)》 CAS 2024年第4期17-24,30,共9页
对不同状态下304不锈钢的里氏硬度分布、超声回波信号、显微组织等进行研究,阐明了里氏硬度离散率、超声波频谱分布等指标与材料劣化状态之间的关系,并运用D-S证据理论将多指标信息融合后,对奥氏体不锈钢材料进行评价。结果表明:正常固... 对不同状态下304不锈钢的里氏硬度分布、超声回波信号、显微组织等进行研究,阐明了里氏硬度离散率、超声波频谱分布等指标与材料劣化状态之间的关系,并运用D-S证据理论将多指标信息融合后,对奥氏体不锈钢材料进行评价。结果表明:正常固溶处理的304不锈钢的硬度离散率小于1.5%,而当材料劣化时,其硬度离散率会显著增大,且超声回波信号的频谱能量分布特征也存在显著变化;采用D-S证据理论对里氏硬度离散率、超声回波的低频能量下降比和高频能量下降比3个指标进行融合,可有效解决评价指标之间的相互冲突问题,显著提高奥氏体不锈钢现场快速评价结果的置信度。 展开更多
关键词 奥氏体不锈钢 D-S证据理论 超声回波 里氏硬度离散率 置信度
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基于小波阈值算法的气体超声波流量计信号预处理
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作者 戈文祺 张坤 刘财智 《计量学报》 CSCD 北大核心 2024年第10期1502-1511,共10页
气体超声波流量计超声信号在气体中传播时,存在易受到各种噪声的干扰,能量衰减严重、回波信号幅值弱、信噪比低等问题,为准确采集气体超声波流量计回波信号,在传统阈值滤波算法基础上提出了一种改进小波阈值算法,对气体超声波流量计信... 气体超声波流量计超声信号在气体中传播时,存在易受到各种噪声的干扰,能量衰减严重、回波信号幅值弱、信噪比低等问题,为准确采集气体超声波流量计回波信号,在传统阈值滤波算法基础上提出了一种改进小波阈值算法,对气体超声波流量计信号进行预处理;将改进小波阈值算法与传统阈值算法进行仿真对比分析,并用FPGA实现对采集超声波信号的6层Coif5小波滤波处理。经仿真与实验对比表明:在不改变超声波信号的特征波基础上,使用改进阈值滤波算法对超声波回波信号降噪处理后,均方根误差为0.0014,信噪比达到了88.3290 dB,该方法提高了超声波流量计的采集质量,实现了良好的降噪效果。 展开更多
关键词 气体超声波流量计 回波信号 信号预处理 改进小波阈值算法
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声共振风传感器用全相位风速风向解算方法
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作者 王飞 王登攀 +4 位作者 王露 曾祥豹 向星旭 廖崧琳 周悦 《压电与声光》 CAS 北大核心 2024年第4期582-585,595,共5页
提出了一种超声波共振式全相位风速风向解算方法,搭建以间距L呈等边三角形分布的3个超声波换能器A、B、C,测量了超声波换能器A、B、C回波初相,根据得到的回波初相解算出从顶点无角度直接吹风和从顶点有角度吹风情况下的风速与风向数据... 提出了一种超声波共振式全相位风速风向解算方法,搭建以间距L呈等边三角形分布的3个超声波换能器A、B、C,测量了超声波换能器A、B、C回波初相,根据得到的回波初相解算出从顶点无角度直接吹风和从顶点有角度吹风情况下的风速与风向数据。结果表明,该文建立的全相位风速风向解算方法连续无奇点,与其他方法相比,在输入量相同的情况下风速波动较小,风向解算较准确。 展开更多
关键词 超声波 共振式 回波初相 全相位风速风向解算方法
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基于脉冲回波法的RTV硅橡胶缺陷超声检测技术研究
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作者 李珂 杨昌建 +5 位作者 尚晓光 柏棣星 边少聪 徐丹 唐子卓 李亚伟 《有机硅材料》 CAS 2024年第6期25-30,共6页
室温硫化(RTV)硅橡胶现场喷涂过程中极易出现深层厚度不均,或混入空气、土壤、微粒等杂质,运行中也会产生裂缝等缺陷,进而降低涂层性能。为快速检测上述缺陷,提出基于超声脉冲回波的RTV硅橡胶缺陷检测方法,该方法采用数字超声波探伤仪... 室温硫化(RTV)硅橡胶现场喷涂过程中极易出现深层厚度不均,或混入空气、土壤、微粒等杂质,运行中也会产生裂缝等缺陷,进而降低涂层性能。为快速检测上述缺陷,提出基于超声脉冲回波的RTV硅橡胶缺陷检测方法,该方法采用数字超声波探伤仪对不同厚度、含有不同尺寸杂质颗粒和条状缺陷的RTV硅橡胶试样进行超声无损检测。结果表明,超声回波检测法可准确地测出RTV硅橡胶的厚度,并检测出0.1~0.8 mm直径范围内的颗粒和条状缺陷,且缺陷尺寸越大,尺寸检测精度越高。 展开更多
关键词 室温硫化 硅橡胶 超声检测 脉冲回波法 缺陷
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RTM成型PMI泡沫夹芯制件界面超声检测异常研究
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作者 赵宏飞 汪晓允 +2 位作者 李明明 胡世林 苏海霞 《合成纤维》 CAS 2024年第2期82-84,共3页
为了研究RTM成型PMI泡沫夹芯制件中PMI泡沫-碳纤维板材间界面超声波C扫描波形差异的影响因素,设计了6组比对试验,采用超声波C扫描测试了不同方法的PMI泡沫夹芯制件的界面。结果表明,薄蒙皮的PMI泡沫夹芯制件在出现分层情况下界面回波达... 为了研究RTM成型PMI泡沫夹芯制件中PMI泡沫-碳纤维板材间界面超声波C扫描波形差异的影响因素,设计了6组比对试验,采用超声波C扫描测试了不同方法的PMI泡沫夹芯制件的界面。结果表明,薄蒙皮的PMI泡沫夹芯制件在出现分层情况下界面回波达到100%,其他回波情况下均不会出现泡沫与蒙皮脱黏情况。 展开更多
关键词 PMI泡沫夹芯制件 RTM 超声波C扫描 回波
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基于概率约束的超声相控阵输煤机工伤缺陷检测
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作者 王雁军 《自动化与仪表》 2024年第4期99-103,共5页
输煤机常处于复杂且恶劣的运行环境中,对其外部探伤过程中,存在信息缺失和遮挡干扰,当前以固定阈值为基础的探查方法容易忽略出现各类工伤缺陷的概率波动,单一阈值很难描述这种概率波动,导致检测效果差。针对上述问题,该文提出超声相控... 输煤机常处于复杂且恶劣的运行环境中,对其外部探伤过程中,存在信息缺失和遮挡干扰,当前以固定阈值为基础的探查方法容易忽略出现各类工伤缺陷的概率波动,单一阈值很难描述这种概率波动,导致检测效果差。针对上述问题,该文提出超声相控阵技术下输煤机工伤缺陷检测方法。分析输煤机工伤缺陷事件类型,计算设备工伤缺陷事件发生概率。以缺陷概率为约束条件,基于超声相控阵列的几何参数,计算平面和凸面超声相控阵聚焦声压,确定回波信号的数据深度。遍历发射阵元和发射通道,通过比较设定阈值的幅度、信号峰值、谷值,判断输煤机是否发生工伤缺陷,实现工伤缺陷检测。实验结果表明,所提方法能够准确检测到输煤机中的所有工伤缺陷。 展开更多
关键词 输煤机 超声相控阵技术 回波信号 发射阵元 超声相控阵声束
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钢结构焊缝缺陷超声波探伤参数的确定及对焊缝质量的影响
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作者 樊亚运 《科学技术创新》 2024年第20期117-120,共4页
本文主要探究了超声波探伤法检测钢结构焊缝质量时各项参数的确定方法,以及焊缝缺陷对于焊缝质量产生的影响。需要确定的参数主要有缺陷回波声程、表面耦合损耗以及缺陷当量和缺陷率等,在此基础上设计超声波探伤试验测试熔透对接焊缝缺... 本文主要探究了超声波探伤法检测钢结构焊缝质量时各项参数的确定方法,以及焊缝缺陷对于焊缝质量产生的影响。需要确定的参数主要有缺陷回波声程、表面耦合损耗以及缺陷当量和缺陷率等,在此基础上设计超声波探伤试验测试熔透对接焊缝缺陷对焊缝抗拉强度的影响。结果表明,在试验条件相同的前提下,焊缝内壁的光滑程度与焊缝缺陷所在位置对焊缝质量有影响。 展开更多
关键词 钢结构 焊缝缺陷 超声波探伤 缺陷回波 抗拉强度
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GH901合金锻件晶粒级别与均匀性对探伤杂波及底波损失的影响
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作者 杨志国 蔡培 +2 位作者 王玉龙 邓冠祥 王宇锋 《模具工业》 2024年第1期55-59,共5页
针对多批次GH901高温合金锻件探伤底波损失与杂波超标不合格的质量问题,开展了多次GH901合金锻造工艺试验,根据锻件不同位置的超声波探伤结果与对应位置晶粒组织进行分析,得出晶粒组织对GH901合金锻件超声波探伤底波损失与杂波的影响。... 针对多批次GH901高温合金锻件探伤底波损失与杂波超标不合格的质量问题,开展了多次GH901合金锻造工艺试验,根据锻件不同位置的超声波探伤结果与对应位置晶粒组织进行分析,得出晶粒组织对GH901合金锻件超声波探伤底波损失与杂波的影响。研究结果表明,GH901合金锻件超声波探伤底波损失与晶粒组织的粗细及均匀性存在对应关系,晶粒越细则超声波探伤底波反射回波越高,杂波低;晶粒越粗则超声波探伤底波反射回波越低,杂波高,当合金锻件晶粒达到2级或更粗时,锻件探伤杂波超标;当GH901合金锻件各区域组织差异较大时,锻件探伤底波损失不合格。 展开更多
关键词 高温合金 晶粒组织 超声波探伤 底波损失 探伤杂波
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