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This study aims to investigate the friction behavior of SiC-B₄C composite ceramics treated by annealing in air sliding against SiC balls.

The dry sliding tests were performed with a ball-on-disk tribometer in ambient air condition. Analysis of friction coefficient, phase compositions of the surfaces, morphologies of worn surfaces of disks and wear scars of balls and surface profiles of wear tracks for disks were carried out using Raman spectroscope, microscope and surface profilometer.

The results show that a self-lubricating layer with the main composition of H₃BO₃ was successfully fabricated on the surface of SiC-B₄C composite ceramics by the annealing treatment in air. When the mass fraction of SiC is more than that of B₄C, SiC-B₄C composite ceramics show higher friction coefficients, the values of which are 0.38 for 80 Wt.%SiC-20 Wt.%B₄C and 0.72 for 60 Wt.%SiC-40 Wt.%B₄C, respectively. SiC-B₄C composite ceramics show lower friction coefficients when the mass fraction of B₄C is more than that of SiC. The low friction coefficients of 40 Wt.%SiC-60 Wt.% B₄C composite ceramics (0.16) and 20 Wt.%SiC-80 Wt.% B₄C composite ceramics (0.20) are attributed to the formation of a sufficient amount of H₃BO₃ layer, rather than the layer of silicon oxides.

This study will help to understand the friction behavior of SiC-B₄C composite ceramics with different ratios of SiC to B₄C treated by annealing in air.

The objective of the present study is to discuss the need for developing a digital library on ceramics.

The rapid growth of digital libraries together with professional publications and the popular press have created a lot of hopes as well as myths about digital libraries. Research on digital libraries began about a decade ago and a number of digital libraries were created as a result. The article begins with giving an overview of digital libraries, and then discusses the need for a digital library on ceramics, highlighting the importance of ceramics on society.

The paper shows that a digital library on ceramics is needed to provide students, scientists, artist and industrial community with an open and interoperable platform to help facilitate research and education, to promote ceramic art, to promote global cooperation, to foster economic development – including rural development, and to help facilitate archaeological research.

It is a paradox that, under circumstances where economic activity takes place at an increasingly global level, individual countries must give increased attention to their performance at the national level so that they can find a favored position within the world community. Since there has been little or no discussion on a digital library on ceramics in the library literature, the study would help developed and developing countries to develop digital library on ceramics.

To reduce the heat load of a gas turbine blade, its surface is covered with an outer layer of ceramics with high thermal resistance. The purpose of this paper is the selection of ceramics with such a low heat conduction coefficient and thickness, so that the permissible metal temperature is not exceeded on the metal-ceramics interface due to the loss ofmechanical properties.

Therefore, for given temperature changes over time on the metal-ceramics interface, temperature changes over time on the inner side of the blade and the assumed initial temperature, the temperature change over time on the outer surface of the ceramics should be determined. The problem presented in this way is a Cauchy type problem. When analyzing the problem, it is taken into account that thermophysical properties of metal and ceramics may depend on temperature. Due to the thin layer of ceramics in relation to the wall thickness, the problem is considered in the area in the flat layer. Thus, a one-dimensional non-stationary heat flow is considered.

The range of stability of the Cauchy problem as a function of time step, thickness of ceramics and thermophysical properties of metal and ceramics are examined. The numerical computations also involved the influence of disturbances in the temperature on metal-ceramics interface on the solution to the inverse problem.

The computational model can be used to analyze the heat flow in gas turbine blades with thermal barrier.

A number of inverse problems of the type considered in the paper are presented in the literature. Inverse problems, especially those Cauchy-type, are ill-conditioned numerically, which means that a small change in the inputs may result in significant errors of the solution. In such a case, regularization of the inverse problem is needed. However, the Cauchy problem presented in the paper does not require regularization.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Aluminum nitride (AlN) ceramics are suitable substrate and package materials for high-power integrated circuits.

Dense AlN ceramics with Y₂O₃ and LaF₃ as sintering additives are prepared. The effects of these additives on the density, phase composition, microstructure and thermal conductivity of AlN ceramics are investigated.

Results show that 2 Wt.% Y₂O₃-doped additive is insufficient for the samples to achieve the full densification sintered at 1,700°C. When LaF₃ is added with Y₂O₃, the samples are perfectly densified at the same sintering condition. The relative density and thermal conductivity of the samples are 97.8-99.07 per cent and 169.104-200.010 W·m-1·K-1, respectively. The density of the samples and their microstructure, especially the content and distribution of secondary phases, is necessary to control the thermal conductivity of AlN ceramics.

Y₂O₃ and LaF₃ additives can effectively promote densification and enhance the thermal conductivity of AlN ceramics in a low sintering temperature, and the AlN ceramics added with Y₂O₃-LaF₃ might have potential applications in package materials for high-power integrated circuits.

This paper aims to investigate the history and distribution of trade ceramics in Southeast Asia over a thousand-year period stretching from the ninth to the early nineteenth century CE.

The study takes a material culture approach to the writing of marketing history by researching the ceramics trade from the starting point of artifacts and their social context. It draws from literatures on Chinese and Southeast Asian ceramics art history and archaeology. It also is informed by first-hand experience inspecting surviving artifacts in shops, talking to dealers and taking in museum displays.

After a brief historical overview of the ceramics trade in Southeast Asia, the research further explores topics in physical distribution (transportation routes, hubs and local marketplaces and ships, cargo and packing) and product assortments, adaptation and globalization of consumer culture.

The art history and archaeological literatures provide a good overview of the ceramics trade and analysis of surviving material artifacts, but only limited information about distribution and consumption. Many questions remain unanswered.

This study contributes to international business and marketing history by documenting a thousand years of trade among China, mainland and insular Southeast Asia, and a long-standing cultural exchange facilitated by seaborne commerce. It also shares a marketing perspective with the fields of Southeast Asian art history and archaeology. Research in marketing history has neglected this region. To fully understand the development of marketing in the pre-industrial era, accounts from civilizations outside the West must be included.

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

This paper seeks to study the metadata requirements for setting up a digital repository in ceramics resources that would provide researchers and ceramic art professionals with access to the information as per their requirements.

The paper first reviews and analyzes various metadata standards and formats already available. Open software (Greenstone) is used to develop the repository and the paper discusses its metadata provisions. Thereafter, the paper focuses on ceramics resources and attempts to determine the metadata elements required to describe and organize ceramic resources. Existing controlled vocabularies to standardize content metadata of the repository are also reviewed.

The paper finds that selected metadata elements of Dublin Core and Categories for the Description of Work of Art can be used to describe and organize the ceramics resources. Local qualifiers are added when necessary to describe the resources. As Categories for the Description of Work of Art metadata standards are not provided in Greenstone, these were defined using GEMS to describe and organize ceramic art works. It also found that existing controlled vocabularies are not sufficient to standardize the content metadata of the repository.

A digital repository should also contain information resources such as video and audio‐video information resources. The study has not considered studying metadata requirements to describe such information resources.

This paper could be useful for others who want to develop their repositories in various disciplines.

The electrical properties of piezoelectric vibrators have a crucial influence on the operating state of ultrasonic motors. In order to solve the problem that the current piezoelectric vibrator generates a large amount of heat during vibration to degrade its performance, which in turn affects the normal operation of ultrasonic motors, this paper prepares a novel piezoelectric vibrator and tests its maximum vibration velocity under the working condition, which is more than twice as much as that of the current commercial PZT-8.

The crystal structures of the samples were analyzed by using an X-ray diffractometer. For microstructure observation, samples were observed by scanning electron microscope (SEM). The quasi-static piezoelectric coefficient meter (ZJ-3AN) was used for piezoelectric measurement. Dielectric properties were measured by utilizing an impedance analyzer (Agilent 4294A) with a laboratory heating unit. Ferroelectric hysteresis loops were obtained using a ferroelectric analyzer (Radiant, Multiferroic 100). A Doppler laser vibrometer (Polytec PSV-300F, Germany) and a power amplifier were used for piezoelectric vibration measurements, during which the temperature rise was determined by an infrared radiation thermometer (Victor 303, China).

The ceramics exhibit enhanced piezoelectric performance at 0.1–0.4 mol% of Yb doping contents. The ceramic of 0.4 mol% Yb reaches the maximal internal bias field and presents a larger mechanical quality factor of 1,692 compared with that of 0.2 mol% Yb-doped ceramic, in spite of a slightly decreased dielectric constant of 439 pC/N, the unit of the piezoelectric constant, which is the ratio of the local charge (pC) to the frontal force (N) and electromechanical coupling coefficient of 0.63. The vibrator with this large mechanical quality factor ceramic displays a vibration velocity of up to 0.81 m/s under the constraint of 20 °C temperature rising, which is much higher than commercial high-power piezoelectric ceramics PZT-8.

The enhanced high-power properties of the piezoelectric vibrator by Yb doping may provide a potential application for the high-performance USM and offer the possibility of long-term stable operation under high power for special equipment like USM. In the subsequent phase of research, the novel PZT-based high-power piezoelectric vibrator can be utilized in the USM, and the motor's performance will be evaluated under aerospace conditions to objectively assess the reliability of the piezoelectric vibrator.

The purpose of this paper is to study the crack‐healing mechanism of ZrO₂/SiC composite ceramics which have a high crack‐healing ability at low temperature.

The effects of dispersed SiC and the environment on crack‐healing behaviour were investigated. The fatigue strength of crack‐healed specimens was also investigated.

The main conclusions are that for crack‐healing of ZrO₂ ceramics, it is necessary to have both a SiC composite and an oxidative environment; and when ZrO₂/SiC composite ceramics are heat‐treated in air, a phase transformation attributable to the SiC composite results in crack‐healing and improvement of fracture toughness and bending strength.

An appropriate heat treatment for ZrO₂/SiC composite caused not only crack‐healing but also the improvement of fracture toughness, and created a multiplier effect on crack‐healing, bending strength and fracture toughness.