Nondestructive Evaluation of Defects in Conductive and Non-Conductive Materials by High-Frequency Signal Transmission Characteristics Technique

2004 ◽  
Vol 270-273 ◽  
pp. 1712-1718
Author(s):  
Kazuhiro Ogawa ◽  
Toshimitsu Baba ◽  
Mikiko Suzuki ◽  
Tetsuo Shoji
Keyword(s):  
Nondestructive Evaluation ◽  
High Frequency ◽  
Signal Transmission ◽  
Transmission Characteristics ◽  
Frequency Signal ◽  
High Frequency Signal ◽  
Conductive Materials

Development of Novel Non-Destructive Inspection Technique Using High-Frequency Signal Transmission Characteristics

2004 ◽  
Vol 261-263 ◽  
pp. 949-954 ◽  
Author(s):  
Toshimitsu Baba ◽  
Kazuhiro Ogawa ◽  
Tetsuo Shoji
Keyword(s):  
High Frequency ◽  
Fatigue Cracks ◽  
Signal Transmission ◽  
Detection Sensitivity ◽  
Transmission Characteristics ◽  
Frequency Signal ◽  
High Frequency Signal ◽  
Significant Difference ◽  
Paramagnetic Materials ◽  
Non Destructive

A novel non-destructive inspection (NDI) technique that utilizes high-frequency signal transmission characteristics was developed as a more reliable, faster and cheaper NDI technique. This technique forms a transmission circuit that includes the specimen, and detects the signals generated by any surface breaking-defect. In this research, quantitative measurement of closed fatigue cracks was implemented via a newly developed probe. The greatest advantage of this technique is that there is no significant difference in detection of defects in either paramagnetic materials or in ferromagnetic materials. Therefore, the potential effects of corrosion, ferrite content, or deformation martensite on the measurement signals are minimized, and a better S/N ratio can be expected. This technique can also be used to measure the size of defects in components, including welded components, and its detection sensitivity is less than 1 mm for surface breaking-defects.

Impedance Matching Using the Smith Chart

2014 ◽  
Vol 701-702 ◽  
pp. 1158-1161
Author(s):  
Jie Yu ◽  
Wen Dong
Keyword(s):  
Circuit Design ◽  
High Frequency ◽  
Signal Transmission ◽  
Impedance Matching ◽  
Basic Requirement ◽  
Frequency Signal ◽  
High Frequency Signal ◽  
Fast Calculation ◽  
Matching Structure ◽  
Smith Chart

Impedance matching is a basic requirement for high frequency signal transmission, but also a relatively complicated aspect in circuit design. In this article, from the perspective of impedance matching, structure principle and characteristics of Smith chart are introduced. On the basis of Smith chart software, its process of impedance matching is described with a simple example to show the advantages of convenient and fast calculation of Smith chart for impedance matching.

Sign in / Sign up

Export Citation Format

Share Document