Ceramics and Ceramic Composites: Materialographic PreparationBy
- G. Elssner, Max-Planck-Institut für Metallforschung, Stuttgart, Germany
- H. Hoven, Forschungszentrum Jülich GmbH, Jülich, Germany
- G. Kiessler, Max-Planck-Institut für Metallforschung, Stuttgart, Germany
- P. Wellner, Sulzer Metco in Hatteresheim, Germany
Ceramics and ceramic composites are now used in almost all areas of technology and have potential for even greater and more widespread applications. To make this a reality, it is increasingly necessary to understand the microstructure of the material and its relationship with properties and performance. Central to this is the characterization of the material, in particular using optical and scanning electron microscopy techniques.
This book acts as an expert guide to the various steps necessary for successful and accurate characterization of these materials including the crucially important preparation stage, the techniques used to reveal the microstructure and the analysis of the results.
In particular, the book presents fundamental information on preparing polished sections of ceramics and ceramic composites including the main steps of sampling, sectioning, mounting and impregnation, and mechanical grinding, lapping and polishing. It discusses microstructural imaging in the optical microscope (OM) and the use of the scanning electron microscope (SEM). Etching or contrast enhancement following final polishing in order to reveal the material's microstructure is also covered.An entire chapter is devoted to material-specific preparation procedures for polished sections. These procedures take into account the properties of the ceramic or composite being examined and the purpose of the examination. They have proven to be very suitable for the respective materials and are effective for revealing the pores. The examples presented here for ceramics and ceramic composites provide polished sections of good to excellent quality for routine examination under the optical microscope. They include tips for etching and contrast enhancement, as well as microstructural images. Chapter 5 discusses the preparation of polished sections for purposes of examination and contains information on producing oblique sections and controlled removal of material. It also addresses the production of thin sections.
As a complement to the examination of the microstructure, chapter 6 provides insight into the evaluation of hardness testing indentations. Chapter 7 concludes this work with an overview of the technical literature.
For materials scientists, metallographers and technicians engaged in characterization of ceramics and ceramic composites.
Published: December 1999
- Abbreviations. Introduction. Fundamentals of Preparing Polished Sections. Selection and sampling. Sectioning. Mounting and impregnation. Hot (compression) mounting. Cold mounting. Recovery of embedded samples. Impregnation. Grinding, lapping, and polishing. Preparation equipment. Grinding. Materialographic lapping. Polishing. Revealing the Microstructure. Microstructural imaging in the Optical Microscope (OM). Imaging methods of optical microscopy. Electronic image processing and contrast enhancement. Tips on contrast enhancement and etching. Relief polishing. Contrast enhancement with interference layers. Chemical dip etching. Thermal etching. Plasma etching. Ion etching. Electrolytic etching. Microstructural imaging in the scanning electron microscope. Ultrasonic scanning microscopy. Material-Specific Preparation of Polished Sections. Properties of ceramic materials. Pores in ceramic materials. Examples of preparing ceramic materials. &agr;-Al2-O3 (corundum) in single-crystal form. Aluminum oxide ceramic: 99.5% &agr;-Al2O3. Aluminum oxide ceramic: 99.7% &agr;-Al2O3. Aluminum oxide ceramic: &agr;-Al2O3 with SiO2 and MgO additives. Aluminum oxide ceramic: &agr;-Al2O3 with glass phase. Aluminum nitride AIN, sintered. Boron carbide B4C, high-density. Boron nitride BN, sintered. Calcium carbonate CaCO3, white marble. Cerium oxide CeO2. Chromite. Refractory ceramics. Glass. Graphite. Coal. Lanthanum strontium manganese oxide. Silicon carbide SiC, pressureless-sintered. Silicon carbide varistor ceramic. Silicon nitride Si3N4, hot-pressed. Si-SiC-C ceramic. Zinc oxide ZnO. Zirconium oxide ZrO2. Zirconium oxide with aluminum oxide inclusions. Zirconium oxide, partially stabilized with MgO and SiO2. Preparation of ceramic composites. Examples of preparing ceramic composites. Active-brazed joint between graphite and a TZM molybdenum alloy. Aluminum alloy reinforced with boron fibers. Flame-sprayed aluminum oxide coating on steel. Glass fiber reinforced plastic. Solder glass/stainless steel joint. Ceramic/cermet composite. Carbon fiber reinforced carbons. Carbon fiber reinforced plastic. Spherical nuclear fuel. Copper coating on an aluminum nitride ceramic. Plasma-sprayed aluminum oxide coating on steel. Plasma-sprayed chromium oxide coating with Ni-20%Cr interlayer on steel. Plasma-sprayed zirconium oxide coating on a nickel super alloy. SiC/C fibers in an aluminum alloy. Titanium carbide coating on graphite. Titanium nitride coating on an inconel alloy. WC-Co carbide metal. Preparing Polished Sections for Examination. Polished sections. Oblique sections. Controlled removal. Thin sections. Preparation of thin sections. Microscopic examination of thin sections. Analysis of Hardness Testing Indentations. Hardness testing of ceramic materials. Determining fracture toughness by indentation hardness Testing. Application of hardness testing to composite layers and surface layers. Indentations in the layer surface. Measuring the layer hardness in the section. Literature. Appendix.