High Sensitivity Moiré

Moire patterns form when two regular patterns of comparable frequency interfere (for example, a screen and its shadow), producing larger patterns that reflect the differences between the two original patterns. These differences can be used as sensitive indicators of changes in shape as objects rotate, heat up, or are otherwise affected by external forces. Applications include nondestructive testing and evaluation, quality control, and process control. The authors have been instrumental in raising moire interference to a high level of sensitivity and extend it to a wide range of fields, including composite materials, ceramics, fracture, and electronic

Klappentext
This book describes both the theory and practice of physical measurements that use high-sensitivity moire - principally moire interferometry. Its focus is on the mechanics and micromechanics of materials and structural elements. Unlike both classical and holographic interferometry, which are best suited for out-of-plane deformation measurements, moire interferometry provides whole-field maps of the in-plane displacements. Normal strains and shear strains are derived directly from the in-plane data. Moire with 2400 lines per mm is typical in practice, yielding a sensitivity of 2.4 moire fringes per micron of displacement. For micromechanics, sensitivity corresponding to 17 nm per fringe contour is demonstrated. Part II is devoted to applications of moire interferometry and microscopic moire interferometry. New studies, not previously published, are included. Diverse fields are addressed: advanced composite materials, thermal stresses, electronic packaging, fracture, metallurgy, time-dependence, strain gage calibration. The methods can be applied for whole-field measurements on nearly and solid body. This reader-friendly book should serve engineers and scientists who are concerned with measurements of real phenomena - and it should stimulate students to pursue the treasures of experimental analysis.

Inhalt
1 Introduction.- 1.1 Our Subject.- 1.2 Scope and Style.- 1.3 History.- 1.4 Comment on Exercises.- 1.5 References.- I.- 2 Elements of Optics.- 3 Geometric Moiré.- 4 Moiré Interferometry.- 5 Microscopic Moiré Interferometry: Very High Sensitivity.- 6 On the Limits of Moiré Interferometry.- II.- 7 Laminated Composites in Compression: Free-edge Effects.- 8 Thermal Stresses Near the Interface of a Bimaterial Joint.- 9 Textile Composites.- 10 Thermal Deformations in Electronic Packaging.- 11 Advanced Composites Studies.- 12 Metallurgy, Fracture, Dynamic Loading.- 13 Strain Standard for Calibration of Electrical Strain Gages.- Appendices.- A Shadow Moiré with Enhanced Sensitivity.- A.1 Introduction.- A.2 Shadow Moiré with O/DFM.- A.3 In-plane Geometric Moiré with O/DFM.- A.4 Reference.- B Submaster Grating Molds.- B.1 Introduction.- B.2 Production of Silicone Rubber Submasters.- B.3 Production of Epoxy Submasters.- B.4 Application of the Reflective Film.- B.5 References.- C Adhesives for Replication of Specimen Gratings.- C.1 Adhesives.- C.2 Addresses.