Location

Snowmass Village, CO

Start Date

1-1-1995 12:00 AM

Description

The penetration depth of microwave signals in a medium is a function of its dielectric properties and the operating frequency [1]. For highly conducting materials such as metals the skin depth is very small. Hence, microwaves can only interrogate the surface features in metals. Surface crack detection and sizing is a significant part of nondestructive evaluation (NDE). In many cases it is an important part of in-service examination of some facilities, such as aircraft fuselage, turbine blades and nuclear power plant steam generator tubings. Since 1991 several new approaches of applying microwaves to surface crack detection have been considered, and experiments have been conducted at the Applied Microwave Nondestructive Testing Laboratory. It has been shown that an open-ended waveguide probe operating at a certain frequency range, polarization and excitation mode can be effectively used for crack detection [2].

Book Title

Review of Progress in Quantitative Nondestructive Evaluation

Volume

14A

Chapter

Chapter 2: Emerging Inspection Technologies

Section

Microwaves

Pages

637-642

DOI

10.1007/978-1-4615-1987-4_78

Language

en

File Format

application/pdf

Share

COinS
 
Jan 1st, 12:00 AM

Higher Order Modes as Indicators of Surface Cracks Under Stratified Dielectric Coatings Using an Open-Ended Waveguide

Snowmass Village, CO

The penetration depth of microwave signals in a medium is a function of its dielectric properties and the operating frequency [1]. For highly conducting materials such as metals the skin depth is very small. Hence, microwaves can only interrogate the surface features in metals. Surface crack detection and sizing is a significant part of nondestructive evaluation (NDE). In many cases it is an important part of in-service examination of some facilities, such as aircraft fuselage, turbine blades and nuclear power plant steam generator tubings. Since 1991 several new approaches of applying microwaves to surface crack detection have been considered, and experiments have been conducted at the Applied Microwave Nondestructive Testing Laboratory. It has been shown that an open-ended waveguide probe operating at a certain frequency range, polarization and excitation mode can be effectively used for crack detection [2].