#### Location

Snowbird, UT, USA

#### Start Date

1-1-1999 12:00 AM

#### Description

Let us assume an isotropic solid with rotational symmetry. If a pulse is injected normal to the surface, this excitation will result in a vibration along the same direction. This is true for any point around the circumference: The rotational symmetry of geometry and material results in a „rotational symmetry“ of the response. If the sample is rotated by an arbitrary angle between two measurements, one finds always the same result. As a consequence, reduction of symmetry (e.g. presence of defect, anisotropy of material, non-rotational geometry) causes an anisotropic response: In most cases the response is a superposition of two oszillations: A resonance split (Fig. 1b).

#### Book Title

Review of Progress in Quantitative Nondestructive Evaluation

#### Volume

18B

#### Chapter

Chapter 7: New Techniques and Applications

#### Section

New Techniques, Applications, and Devices

#### Pages

2039-2045

#### DOI

10.1007/978-1-4615-4791-4_261

#### Copyright Owner

Springer-Verlag US

#### Copyright Date

January 1999

#### Language

en

#### File Format

application/pdf

Rotational Resonance Vibrometry on Ceramic Components

Snowbird, UT, USA

Let us assume an isotropic solid with rotational symmetry. If a pulse is injected normal to the surface, this excitation will result in a vibration along the same direction. This is true for any point around the circumference: The rotational symmetry of geometry and material results in a „rotational symmetry“ of the response. If the sample is rotated by an arbitrary angle between two measurements, one finds always the same result. As a consequence, reduction of symmetry (e.g. presence of defect, anisotropy of material, non-rotational geometry) causes an anisotropic response: In most cases the response is a superposition of two oszillations: A resonance split (Fig. 1b).