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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.

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.

A superconducting material with a composition Y1−xBa2Cu3O7−3/2x − x/2 Bi2O3 (x = 0·1 and 0·2) was synthesised. The influence of Bi2O3 additions on sintering was studied. Preliminary investigations of the Bi‐Sr‐Ca‐Cu‐O system were also made. Thick film pastes, prepared from Y1−xBixBa2Cu3O7 compositions, from the compound YBa2Cu3O7 with 10 w/o addition of Bi2CuO4 and from two compositions in the Bi‐Sr‐Ca‐Cu‐0 system, were fired on Al2O3 and ZrO2 substrates. All thick film materials based on YBa2Cu3O7 compound were superconducting at temperatures above 77 K when fired on ZrO2 substrates, while only a material with the starting composition Y0·8Ba2Cu3O6.7 − 0·1 Bi2O3 reached zero resistivity above 77 K on Al2O3 substrates. Tc (onset) of samples based on the YBa2Cu3O7 compound was around 95 K, and of samples from the Bi‐Sr‐Ca‐Cu‐O system between 95 and 100 K.

The strength of annealed ZrO2/Pd diffusion bonds was found to be weakened after annealing in both air and vacuum. Annealing in air reduces the strength much faster and more severely than in vacuum. Fracture surfaces of as‐bonded joints and those annealed in air and vacuum were studied to characterise the different effects of air and vacuum on the bonded interfaces. Various sizes of precipitates and voids were observed and their distribution on the fractured surfaces was examined by light microscopy. Large precipitates and voids were found close to the edges of the specimen. It is believed that the loss of strength after annealing is an effect of these defects at the highly stressed specimen edges. Transmission and analytical electron microscopy of as‐bonded joints show that an interface layer of very fine grains about 1 micron thick was formed during the bonding process. This layer has a different crystalline structure and composition from both Pd and ZrO2. Characterisation of this layer by electron microscopy is presented in this report. The formation of such a thick interface layer is probably not a pure diffusion process, rather a diffusion and melting process. From the Pd‐Zr phase diagram, there is a range of compositions near a eutectic point where a liquid phase is possible at the bonding temperatures used (1100°C). Taking the Pd‐Zr system as a qualitatively comparable system to Pd‐ZrO2, it is deduced that, at the very beginning of the bonding, Zr and Pd diffuse into each other until the melting composition is reached. The formation of the liquid phase will promote the contact and bonding processes dramatically. This explains why strong bonding cannot be achieved at lower bonding temperatures as was reported in an earlier paper. Similar experiments on Ni/ZrO2 diffusion bonds have also been studied to identify the mechanism of bonding and to compare it with Pd/ZrO2. No reaction was observed at the interface in Ni/ZrO2. Thus the wetting mechanism is absent which explains the formation of a large amount of interface voids and the much weaker bonding strength found in Ni/ZrO2 bonds.

The purpose of this study is to process the wettability surface of the ZrO₂ ceramics to improve their surface friction performance.

Microtexture was processed on the surface of ZrO₂ ceramics using a femtosecond laser. The three-dimensional texture morphology, surface contact angle, friction curve and wear morphology were measured by the laser confocal microscope, the contact angle meter, the reciprocating friction and wear tester and the scanning electron microscope, respectively. Based on Wenzel and partial impalement models, a geometric model of micro pits is established to study the influence mechanism of micro pit depth, diameter and distribution density on wettability and to analyze the relationship between surface wettability and tribological properties.

The results show that changing the geometric characteristics of the texture will lead to a change in the solid-liquid contact mode, and then lead to a change of in the surface contact angle. Wettability is an essential factor that affects the reduction of surface friction. The construction of a reasonable texture can enhance the surface hydrophilicity, which is conducive to the formation of a lubricating film on the ceramic surface, thereby reducing abrasive and adhesive wear, and improving the wear resistance of the ZrO₂ ceramic surface.

The results provide a theoretical reference for femtosecond laser surface texture wettability regulation and tribological performance improvement.

A superconducting material with the composition YBa1.8Pb0.2Cu3O7 was synthesised. The influence of PbO addition on the sintering and formation of the superconducting compound YBa2Cu3O7 was investigated. A thick film paste, prepared from prereacted material and an organic vehicle, was fired on Al2O3 and ZrO2 substrates. The resistivity of samples on ZrO2 substrates decreased to zero around 90 K, while samples on Al2O3 substrates did not reach zero resistivity until 77 K, which is probably due to the differences in thermal expansion coefficient between Al2O3 and the superconducting material. Interactions between Pt alloy based thick film conductors and superconducting material were studied.

This paper aims to provide a review on the process of additive manufacturing of ceramic materials, focusing on partial and full melting of ceramic powder by a high-energy laser beam without the use of binders.

Selective laser sintering or melting (SLS/SLM) techniques are first introduced, followed by analysis of results from silica (SiO₂), zirconia (ZrO₂) and ceramic-reinforced metal matrix composites processed by direct laser sintering and melting.

At the current state of technology, it is still a challenge to fabricate dense ceramic components directly using SLS/SLM. Critical challenges encountered during direct laser melting of ceramic will be discussed, including deposition of ceramic powder layer, interaction between laser and powder particles, dynamic melting and consolidation mechanism of the process and the presence of residual stresses in ceramics processed via SLS/SLM.

Despite the challenges, SLS/SLM still has the potential in fabrication of ceramics. Additional research is needed to understand and establish the optimal interaction between the laser beam and ceramic powder bed for full density part fabrication. Looking into the future, other melting-based techniques for ceramic and composites are presented, along with their potential applications.

The consolidation process and morphology evolution in ceramics-based additive manufacturing (AM) are still not well-understood. As a way to better understand the ceramic selective laser sintering (SLS), a dynamic three-dimensional computational model was developed to forecast thermal behavior of hydroxyapatite (HA) bioceramic.

AM has revolutionized automotive, biomedical and aerospace industries, among many others. AM provides design and geometric freedom, rapid product customization and manufacturing flexibility through its layer-by-layer technique. However, a very limited number of materials are printable because of rapid melting and solidification hysteresis. Melting-solidification dynamics in powder bed fusion are usually correlated with welding, often ignoring the intrinsic properties of the laser irradiation; unsurprisingly, the printable materials are mostly the well-known weldable materials.

The consolidation mechanism of HA was identified during its processing in a ceramic SLS device, then the effect of the laser energy density was studied to see how it affects the processing window. Premature sintering and sintering regimes were revealed and elaborated in detail. The full consolidation beyond sintering was also revealed along with its interaction to baseplate.

These findings provide important insight into the consolidation mechanism of HA ceramics, which will be the cornerstone for extending the range of materials in laser powder bed fusion of ceramics.

Although many researchers have widely studied additive manufacturing (AM) as one of the most important industrial revolutions, few have presented a bibliometric analysis of the published studies in this area. This paper aims to evaluate AM research trends based on 4607 publications most cited from year 2010 to 2020.

The research methodology is bibliometric indicators and network analysis, including analysis based on keywords, citation analysis, productive journal, related published papers and authors indicators. Two free available software were employed VOSviewer and Bibexcel.

Keywords analysis results indicate that among the AM processes, Selective Laser Melting and Fused Deposition Modeling techniques, are the two processes ranked on top of the techniques employed and studied with 35.76% and 20.09% respectively. The citation analysis by VOSviewer software, reveals that the medical applications field and the fabrication of metal parts are the areas that interest researchers greatly. Different new research niches, as pharmaceutical industry, digital construction and food fabrication are growing topics in AM scientific works. This study reveals that journals “Materials & design”, “Advanced materials”, “Acs applied materials & interfaces”, “Additive manufacturing”, “Advanced functional materials” and “Biofabrication” are the most productive and influential in AM scientific research.

The results and conclusions of this work can be used as indicators of trends in AM research and/or as prospects for future studies in this area.

The purpose of this paper is to eliminate Part defects and enrich additive manufacturing of ceramics. Laser powder bed fusion (L-PBF) experiments were carried to investigate the effects of laser parameters and selective oxidation of Titanium (mixed with TiO₂) on the microstructure, surface quality and melting state of Titania. The causes of several L-PBF parts defects were thoroughly analyzed.

Laser power and scanning speed were varied within a specific range (50–125 W and 170–200 mm/s, respectively). Furthermore, varying loads of Ti (1%, 3%, 5% and 15%) were mixed with TiO₂, which was selectively oxidized with laser beam in the presence of oxygen environment.

Part defects such as cracks, pores and uneven grains growth were widely reduced in TiO₂ L-PBF specimens. Increasing the laser power and decreasing the scanning speed shown significant improvements in the surface morphology of TiO₂ ceramics. The amount of Ti material was fully melted and simultaneously changed into TiO₂ by the application of the laser beam. The selective oxidation of Ti material also improved the melting condition, microstructure and surface quality of the specimens.

TiO₂ ceramic specimens were produced through L-PBF process. Increasing the laser power and decreasing the scanning speed is an effective way to sufficiently melt the powders and reduce parts defects. Selective oxidation of Ti by a high power laser beam approach was used to improve the manufacturability of TiO₂ specimens.