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The review glances upon the colorants used for printing on ceramic substrates by ink jet technology and techniques, chemistry involved during the selection of the colorants.

The ink jet technology is an easy and a convenient technique, specially designed colorants are used for such applications with tailor made properties and features.

New developments in technology and chemistry of colorants to achieve successes in application studies of ceramic substrates.

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This review glances upon the history, development and practical approach of the current techniques with available dyes and pigments and the techniques involved during the synthesis and application.

The review paper provides information about the development of the inkjet technique on ceramics and available colorants with methods.

This paper aims to systematically demonstrate a methodology to determine the relative and absolute encapsulation efficiencies (α_Re and α_Ab) for thermally- and chemically-robust inorganic pigments, typically like ZrSiO₄-based pigments, thereby enhancing their coloring performance.

The authors designed a route, surplus alkali-decomposition and subsequently strong-acid dissolution (SAD2) to completely decompose three classic zircon pigments (Pr–ZrSiO₄, Fe₂O₃@ZrSiO₄ and CdS@ZrSiO₄) into clear solutions and preferably used inductively coupled plasma-optical emission spectrometry (ICP-OES) to determine the concentrations of host elements and chromophores, thereby deriving the numeric data and interrelation of α_Re and α_Ab.

Zircon pigments can be thoroughly decomposed into some dissoluble zirconate–silicate resultants by SAD2 at a ratio of the fluxing agent to pigment over 6. ICP-OES is proved more suitable than some other quantification techniques in deriving the compositional concentrations, thereby the values of α_Re and α_Ab, and their transformation coefficient K_RA, which maintains stably within 0.8–0.9 in Fe₂O₃@ZrSiO₄ and CdS@ZrSiO₄ and is slightly reduced to 0.67–0.85 in Pr–ZrSiO₄.

The SAD2 method and encapsulation efficiencies are well applicable for both zircon pigments and the other pigmental or non-pigmental inhomogeneous systems in characterizing their accurate composition.

The authors herein first proposed strict definitions for the relative and absolute encapsulation efficiencies for inorganic pigments, developed a relatively stringent methodology to determine their accurate values and interrelation.

GERMANY Cleaning and pre‐treatment of steel surfaces. Reference is made to the oxygen‐rich surface skin left on steel after rolling, and to its protective powers. Where it has been removed or loosened by accident or design, rusting occurs much more quickly. The nature of the skin and its more or less precarious bond with the base metal are noted, including electrochemical properties that require special attention. In water pipes, etc., exposed to water, corrosive attack appears to be localised and intensified at points where the skin has broken down. It is often considered desirable to remove the skin altogether to ensure more uniform spread of corrosion.

The purpose of this paper is to examine the performance parameters of WEDM to improve the productivity and material removal rate (MRR) with a high surface finish of high chromium-high carbon dies steel.

The experiments were performed on AGIE CUT 220 CNC WEDM. High chromium-high carbon dies steel (D3) was used in the form of a rectangular plate. The workpiece and the brass wire having diameter ɸ 0.25 mm had linked up with +ve and –ve polarity in the DC power source, respectively. De-ionized water having a conductivity level of 0.6 µs/cm was used as the dielectric medium. The dielectric fluid was flushed from the top and bottom nozzles and material was submerged in the dielectric.

The WEDM process parameters for D3 die steel had optimized by using Grey relational analysis method couples with Taguchi method. The optimum solution has been calculated for MRR, cutting speed (Cs), machining time and surface roughness (SR) (Ra value). A fuzzy logic model using Matlab was developed for the prediction of performance parameters, namely MRR, cutting speed (Cs), machining time (M/c time) and SR with respect to changes in input parameters.

The fuzzy model shows the 96.19 percent accuracy between the experimental values and the predicted values.

The optimized parameters by multi-parametric optimization method showed considerable improvement in the process and will facilitate the WEDM, tool and die industries, defense and aerospace industries to improve the productivity with the higher surface finish.

This manuscript represents valid work and the authors have no conflict of interests. The attained optimum outcomes had also been examined through a real experiment and established to be satisfactory.

The main purpose of this work is to explore the erosion wear characteristics of additively manufactured aluminium alloy. Additive manufacturing (AM), also known as three-dimensional (3D) manufacturing, is the process of manufacturing a part designed in a computer environment using different types of materials such as plastic, ceramic, metal or composite. Similar to other materials, aluminum alloys are also exposed to various wear types during operation. Production efficiency needs to be aware of its reactions to wearing mechanisms.

In this study, quartz sands (SiO₂) assisted with oxide ceramics were used in the slurry erosion test setup and its abrasiveness on the AlSi10Mg aluminum alloy material produced by the 3D printer as selective laser melting (SLM) technology was investigated. Quartz was sieved with an average particle size of 302.5 µm, and a slurry environment containing 5, 10 and 15% quartz by weight was prepared. The experiments were carried out at the velocity of 1.88 (250 rpm), 3.76 (500 rpm) and 5.64 m/s (750 rpm) and the impact angles 15, 45 and 75°.

With these experimental studies, it has been determined that the abrasiveness of quartz sand prepared in certain particle sizes is directly related to the particle concentration and particle speed, and that the wear increases with the increase of the concentration and rotational speed. Also, the variation of weight loss and surface roughness of the alloy was investigated after different wear conditions. Surface roughness values at 750 rpm speed, 10% concentration and 75° impingement angle are 0.32 and 0.38 µm for 0 and 90° samples, respectively, with a difference of approximately 18%. Moreover, concerning a sample produced at 0°, the weight loss at 250 rpm at 10% concentration and 45° particle impact angle is 32.8 mg, while the weight loss at 500 rpm 44.4 mg, and weight loss at 750 rpm is 104 mg. Besides, the morphological structures of eroded surfaces were examined using the scanning electron microscope to understand the wear mechanisms.

The researchers verified that this specific coating condition increases the slurry wear resistance of the mentioned steel. There are many studies about slurry wear tests; however, there is no study in the literature about the quartz sand (SiO₂) assisted slurry-erosive wear of AlSi10Mg alloy produced with AM by using SLM technology. This study is needed to fill this gap in the literature and to examine the erosive wear capability of this current material in different environments. The novelty of the study is the use of SiO₂ quartz sands assisted by oxide ceramics in different concentrations for the slurry erosion test setup and the investigations on erosive wear resistance of AlSi10Mg alloy manufactured by AM.

This paper seeks to detail the fabrication of a glass‐ceramic substrate, based on the LiO₂‐ZrO₂‐SiO₂‐Al₂O₃ (LZSA) system, by laminated object manufacturing (LOM) using water‐based cast tapes.

Small amounts of ZrSiO₄ were added to control the thermal expansion coefficient (TEC) of the original glass‐ceramic (LZSA5Zr: LZSA+5 wt% ZrSiO₄). In order to verify the influence of the amount and nature of crystalline phases on the thermal and dielectric behavior of the material, LZSA and LZSA5Zr laminates were sintered at 700°C for 30 min and crystallized at either 800 or 850°C for 30 min.

LZSA laminates (sintered and crystallized at 700 and 800°C, respectively) exhibited a relative density of ∼90 percent, a dielectric constant of 8.39, a dielectric loss tangent of 0.031 and TEC of 5.5×10⁻⁶ K⁻¹ (25‐550°C). The addition of 5 wt% ZrSiO₄ to original LZSA glass‐ceramics led to a nearly constant TEC value of 6×10⁻⁶ K⁻¹ throughout the whole temperature interval (25‐800°C). Dielectric properties of LZSA5Zr did not show any remarkable change when compared to original LZSA.

The thermal, mechanical and electrical properties of LZSA glass‐ceramic laminates fabricated by LOM makes them potential candidates for substrate applications.

The harsh environment of space, especially radiation of direct solar rays, can potentially raise the temperature of the spacecraft to harmful levels. Thermal control coatings (TCCs) fix the thermal condition of the spacecraft acceptable for its components. This is possible by diffusely reflecting all effective ultraviolet (UV), visible (VIS) and near infrared (IR) (NIR) wavelengths of solar radiation and emmition of IR energy. The most commonly used TCCs have used ZnO as a pigment, but absorption of the UV light by ZnO pigment can change the ideal condition of these TCCs. The aim of his study is the using the porous ZnO particles as pigment to prevent the UV absorption.

To enhance the efficiency of these coatings, in the present study, nano-porous zinc oxide particles were synthesized and used as pigments for white TCCs.

The results revealed that the proposed TCC (TPZ), Thermal control coating with porous ZnO had better reflection (scattering) and emittance properties in comparison with the coating using ZnO as a pigment (TZ coating); so this coating had a solar absorptance value equal to 0.141, whereas this value for TZ was 0.150. Furthermore, TPZ showed higher thermal emittance (0.937) in comparison with TZ (0.9). These changes were because of the improvement in the refractive index, shape and surface area of the pigments. The general trend of the scattering coefficients for the prepared coating, as calculated from the Kubelka–Munk equation, showed that scattering was more efficient in the UV region, as compared with the TCC containing ZnO pigments.

This type of pigment for the first time is evaluated in TCCs.

Friction stir processing (FSP) is overviewed with the process variables, along with the thermal aspect of different metals.

With its inbuilt advantages, FSP is used to reduce the failure in the structural integrity of the body panels of automobiles, airplanes and lashing rails. FSP has excellent process ability and surface treatability with good corrosion resistance and high strength at elevated temperatures. Process parameters such as rotation speed of the tool, traverse speed, tool tilt angle, groove design, volume fraction and increase in number of tool passes should be considered for generating a processed and defect-free surface of the workpiece.

FSP process is used for modifying the surface by reinforcement of composites to improve the mechanical properties and results in the ultrafine grain refinement of microstructure. FSP uses the frictional heat and mechanical deformation for achieving the maximum performance using the low-cost tool; the production time is also very less.

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