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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 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.

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.

A novel rapid prototyping technology incorporating a curved layer building style was developed. The new process, based on laminated object manufacturing (LOM), was designed for efficient fabrication of curved layer structures made from ceramics and fiber reinforced composites. A new LOM machine was created, referred to as curved layer LOM. This new machine uses ceramic tapes and fiber prepregs as feedstocks and fabricates curved structures on a curved‐layer by curved‐layer basis. The output of the process is a three‐dimensional “green” ceramic that is capable of being processed to a seamless, fully dense ceramic using traditional techniques. A detailed description is made of the necessary software and hardware for this new process. Also reviewed is the development of ceramic preforms and accompanying process technology for net shape ceramic fabrication. Monolithic ceramic (SiC) and ceramic matrix composite (SiC/SiC) articles were fabricated using both the flat layer and curved layer LOM processes. For making curved layer objects, the curved process afforded the advantages of eliminated stair step effect, increased build speed, reduced waste, reduced need for decubing, and maintenance of continuous fibers in the direction of curvature.

Zirconia ceramics exhibit high strength and fracture toughness. The purpose of this paper is to research a possibility of crack healing in zirconia ceramics.

ZrO₂/SiC composite ceramics are sintered and subjected to three‐point bending. A surface crack of 100 μm in diameter is formed on each specimen. The cracks are healed and the specimens are tested under bending.

The paper finds that ZrO₂/SiC composite ceramic material had a high crack‐healing ability at a considerably low temperature. For example, a crack of 100 μm in diameter is healed even at 600°C.

The paper provides a low temperature healing and a new mechanism of crack healing.

The paper shows the healing temperature and the minimum time required to heal showed a good proportional relation on the Arrhenius plot at temperatures of 600‐800°C. Moreover, the crack healing is caused by SiO₂ cristobalite produced during the healing.

This study aims to investigate soldering of SiC ceramics by using Zn-Al-In-based solders and ultrasonic soldering. The focus was on the quality of soldered joints, examining the boundary of the solder/substrate joint and the strength of the fabricated joints. Moreover, the fractured surfaces of joints were assessed.

The Zn-5Al base, which is considered for eutectic solder, was used in experiments. When manufacturing this solder, In was also added to at 1 Wt.%. The soldering of SiC substrates on a hot plate with ultrasonic assistance was performed.

The solder at room temperature consists of a primary segregated solid solution (Zn) and the binary eutectics (Zn) + (Al) with a high Al content and binary lamellar eutectic with a high Zn and In content non-uniformly distributed on the grain boundaries. The average tensile strength of the Zn5Al1In solder was 52 MPa. The ceramic material was wetted during soldering via reaction between the solder and the SiC substrate, with the formation of Al-Si reaction products. The thickness of the reaction layer on the boundary was 0.5–1.1 µm. The average strength of the soldered joint was 59 MPa. The obtained results confirmed the high efficiency of ultrasonic soldering in air.

This work has characterised Zn5Al1In soldering alloy and examining soldering SiC ceramics by a flux-less ultrasonic process. The analyses were oriented to assess the strength and structure of the solder and the soldered joints. Based on the achieved results, it is possible to predict the suitability of the solder alloy for flux-free soldering of SiC ceramics.

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 aims to investigate the effect of solder alloying with a small amount of La and Y on bond formation with the Si and Cu substrates.

Bi₂La and Bi₂Y solders were studied. Soldering was performed using a fluxless method in air and with ultrasonic activation.

It was found that in the process of ultrasonic soldering, the La and Y were distributed at the interface with Si and Cu substrates, which enhanced the bond formation. Addition of La or Y elements in a Bi-based solder also ensured wetting of non-metallic materials such as Si, Al₂O₃ and SiC ceramics.

The addition of lanthanides offers a method for ensuring wetting of non-metallic materials. The bond with Si was of an adhesive character without the formation of a new contact interlayer. This resulted in lower shear strength of the bond with Si (8-10 MPa). The shear strength of the bond with a Cu substrate was 22-30 MPa.

Electroless plating treatment is one surface modification technique. An added effect due to electroless plating is expected, and the vibration damping capacity of the structures may be improved by this technique. In the present study, the vibration damping capacity of such electroless plated structures is measured experimentally. Damping capacity can be improved regardless of the plated film materials. Improvement efficiency with an electroless plating film with dispersed foreign particles such as SiC ceramics is higher than with a uniform electroless plating film.

The purpose of our paper is to investigate thermal and mechanical properties of Ag sintered layers used for assembly of SiC diode to Direct Bonding Copper (DBC) interposer. How SiC devices are assembled to ceramic package defines efficiency of heat transfer and mechanical support.

Ag microparticles, sized 2-4 μm and flake shaped, were used as joining material. The parameters of sintering process were as follows: temperature 400°C, pressure 10 MPa and time 40 min. It was found that after sintering and long-term aging in air at 350°C the adhesion is in the range of 10 MPa, which is enough from a practical point of view. The thermal properties of the SiC die assembled into a ceramic package were also investigated. In the first step, the calibration of the temperature-sensitive parameter VF (IF = 2 mA) was done and the relation between VF and temperature was found. In the next step, the thermal resistance between junction and case was determined knowing junction and case temperature.

For SiC diode with Au bottom metallization joined to the DBC interposer by Ni/Au metallization by Ag microparticle layer, R_th j-c is in the range of 2-3.5°C/W, and for SiC diode with Ag bottom metallization joined to DBC interposer with Ag metallization by Ag microparticle layer, R_th j-c is in the range of 4.5-5.5°C/W.

In the future, research on thermal resistance of SiC diodes assembled onto the DBC interposer with Au and Ag metallization in the temperature range up to 350°C needs to be carried out. To do this, it necessary to find a solution for the attaches that leads to ceramic package able to work at such high temperature.

Obtained results are comparable with results mentioned by other studies for eutectic Au/Sn or SAC solder joints; however, the solution proposed by us can properly work at significantly higher temperatures.