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Detection and Application of AMI (超声波微成像的主要用途)
Grain boundary structures, Textures 材料的晶格结构
Cracks 裂纹
Delamination, Adhesion, Artefact 分层缺陷、附着物以及其他夹杂物
Particles, inclusions, Precipitations 杂质颗粒、夹杂物、 沉淀物等
ULF <20 Hz
SOUND
Audible 20 Hz – 20 KHz
Ultrasound 20 KHz >
超声的应用：清洗, 焊接, 治疗, 成像和传感 超声波清洗和焊接：20KHz~40KHz 超声波成像：>5MHz
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Ultrasound at Interfaces (界面处的超声波)
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Advantage of Acoustic Micro Imaging (超声波微成像的优点)
超声波显微成像(AMI)利用高频率的超声波(一般在5MHz以上)探 测物体内的结构、缺陷、以及对材料做定性分析。
其优点如下： • Non Destructive (无损检测，非破坏性) • Sensitive inspection technique for bond evaluation (对粘结层面非常敏感) • Penetrates most materials (能穿透大多数的材料) • Subsurface structures (浅表层结构的分析) • Mechanical properties (材料力学性能的检测-非线性超声测试)
Z1 1
MZ a2terial 2
Material 1 Material 2 Plastic Air Ceramic Plastic Copper Plastic
R (%) -100 -82 -87
T (%) 0 18 13
T 2Z2 Z2 Z1
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Frequency, Resolution and
Amplitude
Large Negative
Asymmetric Or 非对称
Polarity
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Acoustic Micro Imaging (超声波微成像U)ltrasound is either Reflected or
Absorbed or Scattered or Blocked by flaws differently than by the surrounding material. (超声波会被
• When an ultrasound pulse impinges on an interface, part of the energy is reflected and part transmitted.
(在界面处的超声波，有些会被反射，有些会穿过该界面。)
• The relative strength of the transmitted (T) and reflected (R) ultrasound at an interface is governed by the acoustic impedance of the materials on each side of the interface.
超声波扫描显微镜 Scanning Acoustic Microscope
Sonoscan D9500
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1. 超声波基础知识 2.超声波扫描微成像工作原理 3. 超声检测设备的参数和软件介绍 4. 超声波成像应用举例 5.超声波检测和X射线检测
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Basics of Ultrasound (超声波基 础)
Penetration
Low Frequency
(频率、分辨率和穿透力) High Frequency
Greatolution
5 MHz
15 MHz
30 MHz
50 MHz
75 MHz
100 MHz
150 MHz
230 MHz
300 MHz
Sample Surface
Voids, Holes,bubbles, 空洞、空隙、气泡等
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2、超声波扫描微成像工作原理
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Determining Echo Polarity (确定回声正负极性)
CASE 1 Z2 > Z1 (由软---硬是正波)
R/I = (Z2 - Z1)
(Z2 + Z1)
Incident
Reflected
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Ultrasound at Interfaces (界面处的 超声波)
Reflected wave (反射波)
Reflection Coefficient (R) (反射系数R)
Transmitted wave (穿透波)
Transmission Coefficient (T) (穿透系数T)
R Z2 Z1 Z2 Z1
Sample Back Surface
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Classification (超声波功能仪器的分类)
声纳：
分辨率范围 m-cm
频率范围 20KHz-500KHz
医用 B超：
分辨率范围 cm-mm
频率范围 500KHz-1MHz
超声波显微镜：
分辨率范围 mm-μm-nm 频率范围 5MHz-2GHz
CASE 2 Z2 < Z1 (由硬----软是负波)
Z1
CASE 3 Z2 = Z1
(材质没有变化)
Z2 两种物质的声阻抗的差异决定反射波
(回声)的正负极性和幅值
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Color Mapping (着色图)
Large Positive Positive
No Signal Negative
Symmetric Or 对称
(在界面处超声波反射和穿过的相对强度是由界面两边物质的声阻抗决定的。)
• Acoustic Impedance (Z) - the product of the density of the material and the velocity of ultrasound (Z =V).
(声阻抗是物质的密度和超声波在该物质中的传播速度的乘积。)
材料反射、散射、吸收或是阻挡。)
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Graphical Presentation of Working Principle