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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.

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.

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.

The purpose of this study is to investigate the effect of the incorporated zirconia (ZrO₂) nanoparticles on the performance of the deposited layer Ni–Cu alloy on steel sheet.

The aim was to produce Ni–Cu–ZrO₂ nanocomposite coatings by electrodeposition technique and estimate the influence of ZrO2 nanoparticles on the performance of Ni–Cu alloy. The surface morphologies and chemical compositions of the deposited layers were assessed using scanning electron microscopy and energy-dispersive X-ray analysis, respectively. Nanoindentation was used as a well-advanced technique for measuring microhardness and Young’s modulus values of different coatings. The corrosion resistance in 3.5 per cent NaCl solution of electrodeposited films has been investigated.

The main conclusion is that the surface morphologies of Ni–Cu–ZrO2 nanocomposite coatings were fine granular compared with Ni–Cu alloy. The corrosion behavior illustrated that the incorporation of ZrO₂ nanoparticles with Ni–Cu film improved the corrosion resistance. Significant improvement was also demonstrated in the hardness of nanocomposite coatings.

The optimized industrial use of steel-coated Ni–Cu alloy with super properties. Consequently, a social benefit can be associated with the reduction in the corrosion rate and increases the microhardness and Young’s modulus.

The results presented in this work are an insight into understanding the incorporation of ceramic reinforcement with metal or alloy films (matrix) on carbon steel using the electrodeposition technique. The development of corrosion resistance of Ni–Cu alloys has been considered as a promising behavior. In this work, a consistent assessment of the results achieved on laboratory scale has been conducted.

This study aims to develop a less weight high wear resistant material to fabricate brake components especially in automotive sector.

Effort was initiated to design and develop aluminium metal matrix composite by combining aluminium alloy AA6061 and zirconium oxide (ZrO₂) with the help of stir casting coupled with squeeze casting unit. Morphology analysis of advanced composite has been carried out by optical microscopy and scanning electron microscopy (SEM). The hardness of composites having different compositions was tested using Vickers micro hardness tester. The tribological property of the developed three specimens having different composition has been tested using pin-on-disc wear test equipment under dry sliding conditions. To obtain better understanding of wear mechanism, SEM image of worn-out surface was captured and analysed. SEM images and the corresponding Energy-dispersive X-ray spectroscopy (EDX) on the wear surface were carried out.

The optical and SEM images evidenced the existence of ZrO₂ particles along the metal matrix composite. Porosity values shows that the porosity level is acceptable as it falls below 7 per cent. Also, the finding proves that increase in the percentage of reinforcement particle instigates agglomeration on the AA6061 composites. Hardness test demonstrated that the inclusion of hard ZrO₂ particles leads to substantial improvement in hardness and the hardness value started deteriorating when the composition reaches 15 per cent. The wear test results substantiated the enhancement of tribological property due to the inclusion of distinct ZrO₂ particles. Also, despite of addition of reinforcements, the wear rate increased when the load increases. SEM images proved that AA6061/ZrO2-5 per cent composite fashioned steady-state mild and smooth wear. EDX spectrum analysis revealed the existence of ZrO₂ particles along with wear debris, which caused wear of 685 µm in AA6061/ZrO₂-15 per cent composite.

The developed material possesses low wear rate which is the unique property of composite and frictional force which is directly proportional to load but the coefficient of friction remains apparently constant. As a whole, investigations on developed composites introduce a new material which is suitable for manufacturing of brake components for automobile industry.

The main purpose of this study is to enhance bio-tribological properties of Ti6Al4V and the surface-modified layers of Ni⁺/N⁺-implanted Ti6Al4V alloy, bionic texturing was done on Ti6Al4V surface.

The phase compositions and nano-hardness of the surface-modified layers of the samples have been analyzed by X-ray diffractometer and Nano Indenter, respectively. This paper has conducted bio-tribological tests under artificial saliva, sodium hyalurate and sodium hyalurate +γ-globulin by micro tribology multifunction tribometer, with ZrO2 ball/modified layer as the friction pair. S-3000N scanning electron microscope has been used to analyze the morphology of the surface-modified layers and scratches of the ones after the bio-tribological tests.

The results show that the surface-modified layers were mainly composed of Ti₂Ni and Ti₂N. Moreover, bionic texturing can obviously increase the contents of Ti₂Ni and Ti₂N that were formed on the surface of Ni⁺/N⁺-implanted Ti6Al4V alloy, and enhance the nano-hardness of the surface-modified layers. It could also reduce the friction coefficients of the surface-modified layers, and render the modified layers more wear-resistant.

The surface bio-tribological properties of Ti6Al4V have been enhanced by ion implantation technique and bionic texturing in this paper; this provided a new method for the research of related fields.

High temperature oxidation and hot corrosion behaviour of some ceramic‐based coatings, e.g. borate, silicate‐chromate and carbide‐oxide on mild steel has been investigated in the temperature range of 400–850°C. The coated steel in general shows much better oxidation and hot corrosion resistance than the uncoated steel specially at higher temperatures. The borate coating has better hot corrosion resistance performance between 700 and 800°C whereas silicate‐chromate is suitable at temperatures above 800°C. The coated steels show parabolic behaviour during oxidation. In presence of Na2SO4, the corrosion rate increases with increasing salt concentration till a maxima is reached. The amount of Na2SO4 corresponding to the maximum corrosion rate decreases with increasing temperature. A self‐sustained fluxing cum sulphidation mechanism has been proposed to explain hot corrosion behaviour of uncoated or coated mild steel.

Thick‐film technology to implement passive elements, network and hybrid circuits has been widely used for four decades and its importance is still growing. While on one hand the technology has been improved to meet the requirements for more sophisticated circuits, on the other hand a better knowledge of its outstanding properties has promoted its application to a certain number of sometimes exotic devices, many of which are in the sensor and actuator area. This paper presents examples of a variety of applications to illustrate what thick film technology can offer outside the familiar area, and to stimulate the imagination of scientists towards possible new applications.

This paper aims to clarify the friction properties of 304 steel surface modification. The surface modification includes laser texturing processing and nitriding treatment on 304 steel surface, and then the friction properties’ test was conducted on different friction directions and different upper test samples by using microfriction and wear testing machine.

The diameter and spacing of 100-, 150-, 200-, 300-μm pit array on the surface of 304 steel were calculated using a M-DPSS-50 semiconductor laser device. Then, the textured surface was nitriding-treated using a nitriding salt bath device. The chemical composition, surface morphology and surface microhardness of the composite-modified surface were measured by X-ray diffraction and by using an optical microscope and a microhardness tester. The tribological characteristics of the composite-modified surface were tested by MRTR microcomputer-controlled multifunctional friction and wear testing machine.

The result showed that a rule pit texture surface was obtained by the texture processing. The microhardness of nitriding treatment surface reached 574.27HV0.1, which significantly higher than 222.58HV0.1 of 304 steel. The composite-modified surface has excellent anti-friction and wear resistance properties when the upper specimen was GCr15 steel and ZrO2, respectively. The composite-modified surface has excellent anti-friction and anti-wear properties after long time friction under different angles. However, the friction coefficient and wear morphology of the friction pairs are not affected by the friction angle.

Because of the chosen research approach, the research results may lack generalizability. Therefore, researchers are encouraged to test the proposed propositions further.

The paper conducted a systematic study of the tribological characteristics of 304 steel composite modification surface and provided a good basis for the extensive application of 304 steel.

The study provides a good basis for the extensive application of 304 steel.

This paper fulfils an identified need to study the extensive application of 304 steel.

Thick film superconductors with the nominal composition Bi2Pb0.5Sr2Ca2.5Cu3.5Ox were fired on stainless steel substrates and on alumina substrates covered with silver or gold thick film conductors. Films on stainless steel substrates were semiconducting due to reaction between the superconducting film and oxidised chromium and iron from the steel. Tc(R=0) of films on silver was between 80 K and 90 K while Tc (R=0) on gold was below 60 K. The low Tc (R=0) of films on gold is attributed to the interaction between the gold layer and copper from the superconductor.