Search Results for optical microscopes

Moore's Law has driven many degree circuit features below the resolving capability of optical microscopy. Yet the optical microscope remains a valuable tool in failure analysis. This article describes the physics governing resolution and useful techniques for extracting the small details. It begins with the basic microscope column and construction. The article discusses microscope adjustments, brightfield and darkfield illumination, and microscope concepts important to liquid crystal techniques. It also discusses solid immersion lenses, infrared and ultraviolet microscopy and concludes with laser microscopy techniques such as thermal induced voltage alteration and external induced voltage alteration.

This appendix contains detailed micrographs of nickel- and cobalt-base superalloys selected to illustrate the microstructural features described in this book.

The mechanical properties of steel are strongly influenced by the underlying microstructure, which is readily observed using optical microscopy. This chapter describes common room-temperature steel microstructures and how they are achieved via heat treatment. It discusses the production of hypo- and hypereutectoid steels and the effect of cooling rate on microstructure. It also examines quenched steels and the phase transformations associated with rapid cooling. It describes the development of lath and plate martensite, retained austenite, and bainite and how to identify the various phases. The chapter concludes with a brief review of spheroidized microstructures.

This chapter explains how to prepare material samples for optical microscopy, the most common method for characterizing the microstructure of cast iron and steel. It provides information on sectioning, mounting, polishing, etching, and recording. It describes the nature of surface roughness, the factors that contribute to it, and its effect on image quality. It discusses the use of fixturing and holding devices, includes photographic examples of polishing defects and drying marks, and provides an overview of micrographic etchants and the features they reveal. It also describes the steps involved in replicating part surfaces.