Significant progress has been made in recent years in developing silicon nitride ceramics. The advances that have been achieved are mainly based on an increasing understanding of processing and microstructure-properties relationships. New analytical methods and high resolution transmission electron microscopy (HRTEM) coupled with extensive phase equilibria studies have provided new insights into the grain boundary region and offer the possibility to tailor the microstructure for specific applications. Because of the anticipated break-through in industrial applications there are still considerablt; research activities at industrial laboratories as well as other research centres. This volume presents the contributions to the international workshop "Tailoring ofHigh- Temperature Properties of Si3N4-Ceramics" with 60 participants from 12 countries held on 6th - 9th October 1993 at SchloB Ringberg in Germany, the conference site of the Max- Planck-Society. Additionally, it contains all invited papers of the International Conference "Silicon Nitride 93" held before the workshop on 4th - 6th October 1993 in Stuttgart/Germany. The book covers all recent research activities on silicon nitride ceramics and gives an overview with respect to recent developments.

The nitrides and carbides of boron and silicon are proving to be an excellent choice when selecting materials for the design of devices that are to be employed under particularly demanding environmental and thermal con- tions. The high degree of cross-linking, due to the preferred coordination numbers of the predominantly covalently bonded constituents equalling or exceeding three, lends these non-oxidic ceramics a high kinetic stability, and is regarded as the microscopic origin of their impressive thermal and mechanical durability. Thus it does not come as a surprise that the chemistry, the physical properties and the engineering of the corresponding binary, ternary, and even quaternary compounds have been the subject of intensive and sustained efforts in research and development. In the five reviews presented in the volumes 101 and 102 of "Structure and Bonding" an attempt has been made to cover both the essential and the most recent advances achieved in this particular field of materials research. The scope of the individual contributions is such as to address both graduate students, specializing in ceramic materials, and all scientists in academia or industry dealing with materials research and development. Each review provides, in its introductory part, the chemical, physical and, to some extent, historical background of the respective material, and then focuses on the most relevant and the most recent achievements.

Recent developments in advanced ceramics are critically evaluated in respect to their thermal shock and thermal fatigue behavior from an interdisciplinary viewpoint by leading experts. The book covers the aspects of material development, mechanical and fracture mechanical models and experimental testing methods. Special emphasis is given to the influence of a rising crack resistance on the thermal shock behavior, novel irradiation testing methods for a quantitative characterization of the thermal shock and fatigue loading as well as detailed fracture mechanical models for single and multiple crack propagation. This book summarizes developments of the last decade concerning the thermal shock and thermal fatigue behavior of advanced ceramics. The scientific articles of the book were carefully arranged in order to achieve a textbook-like form which will be of great value to researchers and students. (ABSTRACT) This book summarizes developments of the last decade concerning the thermal shock and thermal fatigue behavior of advanced ceramics. The book covers the aspects of material development, mechanical and fracture mechanical models and testing methods. The scientific articles were carefully arranged in order to achieve a textbook-like form which will be of great value to researchers and students.

The nitrides and carbides of boron and silicon are proving to be an excellent choice when selecting materials for the design of devices that are to be employed under particularly demanding environmental and thermal con- tions. The high degree of cross-linking, due to the preferred coordination numbers of the predominantly covalently bonded constituents equalling or exceeding three, lends these non-oxidic ceramics a high kinetic stability, and is regarded as the microscopic origin of their impressive thermal and mechanical durability. Thus it does not come as a surprise that the chemistry, the physical properties and the engineering of the corresponding binary, ternary, and even quaternary compounds have been the subject of intensive and sustained efforts in research and development. In the five reviews presented in the volumes 101 and 102 of "Structure and Bonding" an attempt has been made to cover both the essential and the most recent advances achieved in this particular field of materials research. The scope of the individual contributions is such as to address both graduate students, specializing in ceramic materials, and all scientists in academia or industry dealing with materials research and development. Each review provides, in its introductory part, the chemical, physical and, to some extent, historical background of the respective material, and then focuses on the most relevant and the most recent achievements.

Significant progress has been made in recent years in developing silicon nitride ceramics. The advances that have been achieved are mainly based on an increasing understanding of processing and microstructure-properties relationships. New analytical methods and high resolution transmission electron microscopy (HRTEM) coupled with extensive phase equilibria studies have provided new insights into the grain boundary region and offer the possibility to tailor the microstructure for specific applications. Because of the anticipated break-through in industrial applications there are still considerablt; research activities at industrial laboratories as well as other research centres. This volume presents the contributions to the international workshop "Tailoring ofHigh- Temperature Properties of Si3N4-Ceramics" with 60 participants from 12 countries held on 6th - 9th October 1993 at SchloB Ringberg in Germany, the conference site of the Max- Planck-Society. Additionally, it contains all invited papers of the International Conference "Silicon Nitride 93" held before the workshop on 4th - 6th October 1993 in Stuttgart/Germany. The book covers all recent research activities on silicon nitride ceramics and gives an overview with respect to recent developments.

Recent developments in advanced ceramics are critically evaluated in respect to their thermal shock and thermal fatigue behavior from an interdisciplinary viewpoint by leading experts. The book covers the aspects of material development, mechanical and fracture mechanical models and experimental testing methods. Special emphasis is given to the influence of a rising crack resistance on the thermal shock behavior, novel irradiation testing methods for a quantitative characterization of the thermal shock and fatigue loading as well as detailed fracture mechanical models for single and multiple crack propagation. This book summarizes developments of the last decade concerning the thermal shock and thermal fatigue behavior of advanced ceramics. The scientific articles of the book were carefully arranged in order to achieve a textbook-like form which will be of great value to researchers and students. (ABSTRACT) This book summarizes developments of the last decade concerning the thermal shock and thermal fatigue behavior of advanced ceramics. The book covers the aspects of material development, mechanical and fracture mechanical models and testing methods. The scientific articles were carefully arranged in order to achieve a textbook-like form which will be of great value to researchers and students.

Der Mensch bedient sich seit jeher mineralischer Rohstoffe im Kampf urn sein Bestehen und zur Befriedigung seiner kultureHen Bedurfnisse. Die Art der Nutzung hat sich im Lauf der Zeit naturlich sehr geandert: yom Gebrauch einfachster Steinwerkzeuge zu Produkten komplizierter moderner Technologien. Und diese Entwicklung geht selbstverstandlich weiter. Eine wichtige praktische Aufgabe der N aturwissenschaften und der Bergbauwissenschaften ist es folglich, die Grundlagen fur die Versorgung von Technik und Wirtschaft mit den notwendigen Rohstoffen zu liefern; der Dynamik der Entwicklungen mit ihren wechselnden Bedurfnissen ist Rechnung zu tragen. In der Osterreichischen Akademie der Wissenschaften wird dieser Fragenkomplex in der "Kommission fur Grundlagen der Mineralrohstoff-Forschung" behandelt. Diese hat in den letzten J ahren vor aHem die Bearbeitung von Einzelproblemen der Lagerstattenforschung im weitesten Sinn unterstutzt oder durch ihre Mitglieder durchgefuhrt. Mit der vorliegenden Schrift versucht sie, einer zukunftsorientierten Frage gerecht zu werden: der Versorgungslage neuer Technologien mit minerali- schen Rohstoffen. Trotzdem heute selbst weltweite Transportwege fur die Wirtschaft keine entscheidende Rolle spielen, ist es beim Auf und Ab der Welt- marktpreise und bei der Moglichkeit internationaler politischer Turbulenzen fur jeden Staat und fur jedes Wirtschaftsgebiet dringend notwendig, uber Rohstoff- queHen im eigenen Bereich genau Bescheid zu wissen. Dieser Aufgabe mochte die vorliegende Schrift dienen, wobei die Belange Osterreichs besondere Beachtung finden.