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The quantum of metal particle waste generation in manufacturing industries is posing a great concern for the environment. The iron forging industries generate a huge amount of grinding sludge (GS) waste, which is disposed into the earth. The accumulation of this waste in dump yards causes an increase in soil and air pollution levels.

In the current investigation, an effort was made to use this waste GS for the progress of aluminum-based composite. To maintain uniform distribution of reinforcing material, the friction stir processing technique was used.

The characterization based on the SEM image of the Al/GS composite revealed that uniform dispersal of reinforcement content can be attained in a single tool pass. Number of grains/inch was approximately 2,402. XRD of GS powder confirmed the presence of SiO₂, Fe₂O₃, Al₂O₃ and CaO phases. These phases proved GS to be a better reinforcement with aluminum alloy. Tensile strength and hardness were significantly improved in comparison to the aluminum alloy. Thermal expansion and corrosion weight loss were evaluated to observe the influence of GS addition.

The studies proved that the use of GS as reinforcement material can help in curbing the menace of soil pollution to a large extent.

Silicone resin based protective coatings are generally used for high temperature applications. In this work, anti‐corrosive and heat resistant properties of titanium dioxide, mica, zirconium oxide and quartz combination pigments with silicone resin as carrier vehicle in primer and top coat for mild steel surface have been evaluated. Promising results were obtained, showing that the ceramic pigments (zirconium oxide and quartz) impart heat‐resistance protection for steel substrate up to 370°. Electro‐chemical impedance spectroscopy, immersion studies and salt spray test results show good corrosion protection for the steel surface.

The purpose of this paper is to report the effect of sputtering time on the electrical and physical properties of ZrO_x. ZrO_x (measured thickness is ranging from 20.5 to 51.3 nm) thin films as gate oxide materials are formed by metal deposition at different sputtering time and thermal oxidation techniques.

Zirconium is deposited on silicon substrate at three different sputtering time; 30‐, 60‐ and 120‐s continued with an oxidation process conducted at 500°C for 15 min to form ZrO_x thin films. High‐resolution X‐ray diffraction (HR‐XRD), Fourier transform infrared (FTIR) spectroscopy and electrical characterizations were used to examine the properties of the thin film.

A broad ZrO_x peak lies in between 26° and 31° from HR‐XRD is presumed as the effect of small thickness of ZrO_x and or the ZrO_x is still partially crystalline. FTIR spectroscopy results suggested that besides ZrO_x, SiO_x interfacial layer (IL) has also formed in all of the investigated samples. As the sputtering time increases, hysteresis between the forward and reverse bias of capacitance‐voltage curve has reduced. The lowest leakage current density and the highest oxide breakdown voltage have been demonstrated by 60‐s sputtered sample. These may be attributed to a lower effective oxide charge and interface trap density. The extracted dielectric constant (κ) of these oxides is ranging from 9.4 to 18, in which the κ value increases with the increase in sputtering time.

ZrO_x thin film which was fabricated by sputtering method at different sputtering time and thermal oxidation techniques showed distinctive electrical results. SiO_x IL formed in the samples.

A sol-gel process has been successfully utilized to form hybrid materials of poly(vinyl butyral) (PVB) and zirconium dioxide (zirconia). The gelation occurred due to the interaction between remaining hydroxyl group of PVB and zirconia. The hybrids showed good optical transparency and significant improvement in Young's modulus, dynamic mechanical property, abrasion resistance and impact resistance. The glass transition temperature of PVB shifted to higher temperatures by hybridization of PVB and zirconia.

This paper aims to study the deposition of ZrO₂ on 316L stainless steel surface using cathodic plasma electrolytic deposition (CPED) technique in potassium hexafluorozirconate (K₂ZrF₆) electrolyte solution to promote its corrosion and tribological properties.

Plasma electrolytic oxidizing (PEO) technique is commonly used to form zirconium dioxide (ZrO₂) on various substrates. But, in this paper, cathodic type of this technique (CPED) was used.

Composition of the surface layer was analyzed by X-ray diffraction (XRD) and the formation of ZrO₂ on the substrate was confirmed. Scanning electron microscope (SEM) was used to observe the unique morphology of the surface layer. The corrosion resistance of the coated surface was investigated by electrochemical methods involving cyclic voltammetery in Ringer’s solution. The treated sample showed a better pitting resistance. Pin-on-disk wear tests revealed that the friction coefficient of the coated sample is lower than that of the substrate. Also, it was shown that hardness and roughness of the coated sample increased after plasma electrolytic treatment.

This paper considers the CPED of ZrO₂ coating on 316L stainless steel. Some recent research works with ZrO₂ coating have been prepared by PEO. There is limited or no record on the study of ZrO₂ coatings by CPED process. In this study, the effort has been made to prepare a zirconia (ZrO₂) coating on the stainless steel substrate through cathodic plasma electrolytic process under 200 V. Due to the excellent wear resistance, ZrO₂ may be used as a high resistant and protective coating on stainless steels, which are widely used in industries and biomedical applications.

The research on lead-free solder alloys has increased in past decades due to awareness of the environmental impact of lead contents in soldering alloys. This has led to the introduction and development of different grades of lead-free solder alloys in the global market. Tin-silver-copper is a lead-free alloy which has been acknowledged by different consortia as a good alternative to conventional tin-lead alloy. The purpose of this paper is to provide comprehensive knowledge about the tin-silver-copper series.

The approach of this study reviews the microstructure and some other properties of tin-silver-copper series after the addition of indium, titanium, iron, zinc, zirconium, bismuth, nickel, antimony, gallium, aluminium, cerium, lanthanum, yttrium, erbium, praseodymium, neodymium, ytterbium, nanoparticles of nickel, cobalt, silicon carbide, aluminium oxide, zinc oxide, titanium dioxide, cerium oxide, zirconium oxide and titanium diboride, as well as carbon nanotubes, nickel-coated carbon nanotubes, single-walled carbon nanotubes and graphene-nano-sheets.

The current paper presents a comprehensive review of the tin-silver-copper solder series with possible solutions for improving their microstructure, melting point, mechanical properties and wettability through the addition of different elements/nanoparticles and other materials.

This paper summarises the useful findings of the tin-silver-copper series comprehensively. This information will assist in future work for the design and development of novel lead-free solder alloys.

This study aims to investigate the optimal process parameters of the wire-cut electrical discharge machining (WCEDM) for the machining of the GZR-AA7475 hybrid metal matrix composite (HMMC). HMMCs are prepared with 2 Wt.% graphite and 4 Wt.% zirconium dioxide reinforced with aluminium alloy 7475 (GZR-AA7475) composite by using the stir casting method. The objective is to enhance the mechanical properties of the material while preserving its unique features. WCEDM with a 0.18 mm molybdenum wire electrode is used for machining the composite.

To conduct experimental studies, a Taguchi L27 orthogonal array was adopted. Input variables such as peak current (I_p), pulse-on-time (T_ON) and flushing pressure (P_F) were used. The effect of process parameters on the output responses, such as material removal rate (MRR), surface roughness rate (SRR) and wire wear ratio (WWR), were investigated. The grey relational analysis (GRA) is used to obtain the optimal combination of the process parameters. Analysis of variance (ANOVA) was also used to identify the significant process parameters affecting the output responses.

Results from the current study concluded that the optimal condition for grey relational grade is obtained at T_ON = 105 µs, I_p = 100 A and P_F = 90 kg/cm². Peak current is the most prominent parameter influencing the MRR, whereas SRR and WRR are highly influenced by flushing pressure.

Identifying the optimal process parameters in WCEDM for machining of GZR-AA7475 HMMC. ANOVA and GRA are used to obtain the optimal combination of the process parameters.

The purpose of this study is to investigate the structural, surface roughness and corrosion properties of the zirconium oxide thin films deposited onto SS304 substrates using the direct current (DC) magnetron sputtering technique.

DC sputtering at different powers – 80, 100 and 120 W – was used to deposit ZrO₂ thin films onto different substrates (Si/SS304) without annealing of the substrate. Atomic force microscope (AFM), energy-dispersive X-ray spectroscopy (EDS), Tafel extrapolation and contact angle techniques were applied to investigate the surface roughness, chemical compositions, corrosion behavior and hydrophobicity of these films.

Results showed that the thickness of the deposited film increased with power increase, while the corrosion current decreased with power increase. AFM images indicated that the surface roughness decreased with an increase in DC power. EDS analysis showed that the thin film has a stoichiometric ZrO₂ (Zr:O 1:2) composition with basic uniformity. Water contact angle measurements indicated that the hydrophobicity of the synthesized films decreased with an increase in surface roughness.

DC magnetron sputtering technique is infrequently used to deposition thin films. The obtained thin films showed good hydrophobic and anticorrosion properties. Finally, results are compared with other deposition techniques.

Over the last 50 years the element titanium has been steadily gaining in importance. The major interests range from titanium metal, which combines good resistance to corrosion with high strength and low specific gravity, to the white pigment, titanium dioxide, and titanium tetrachloride, a chemical intermediate. This paper reviews the manufacture of these materials and particularly deals with the properties and applications of titanium dioxide, which, by reason of its high refractive index, possesses outstanding lightening and hiding power, making it the first choice among white pigments.

Aluminium is the most proficiently and commonly used metal due to its desirable physical, chemical and mechanical properties. When Aluminium reinforced with hard ceramic particles, shows increased strength and good corrosion resistant and wear resistant qualities. In the present investigation, A390 + X vol. % Zro₂ (X = 5, 10 and 15) composites have been fabricated through P/M technique.

After that the microstructural properties are tested by scanning electron microscope (SEM) analysis wear test is performed using pin-on-disc machine.

The wear conditions of applied load 30N and sliding velocity 1 m/s and track distance 1000m was followed. A390 + 15% Zro₂ of surface of the composites unveiled greater hardness when compared with A390 alloy.

A390 + 15% Zro₂ exhibited superior wear resistance than that of the matrix alloy. Thus the material proves as an excellent solution for applications that requires high wear resistance.