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The purpose of this paper is to obtain iron‐enriched Fe‐Ni alloy foil on Ti substrates with good quality from a chloride‐sulfate bath used in a normal DC plating mode. The effects of iron content on the hardness, surface morphology and microstructure of the foil were clarified.

Fe‐Ni alloy foil was prepared by electrodeposition in a chloride‐sulfate based solution. The effects of current density, temperature, stirring rate and sodium propargyl sulfonate concentration on the iron contents of the Fe‐Ni alloy foils were studied. The phase composition and surface morphology with various iron contents were characterized by X‐ray diffraction (XRD) and atomic force microscopy (AFM), respectively. Cathodic polarization curves were used to evaluate the role of sodium propargyl sulfonate (PS).

Nanocrystalline Fe‐Ni alloy foil containing up to 64 wt. percent iron can be obtained from a chloride‐sulfate based solution. The foil converts from a face‐centered cubic (fcc) Fe3Ni2 phase to a mixture of fcc and body‐centered cubic (bcc) Fe7Ni3 with increase in iron content from 55.0 wt. percent to 63.5 wt. percent. AFM studies revealed that the foil had a fine grain structure with a roughness of 30 nm and grain size of 30 nm. With iron increasing to 63.5 wt. percent some islands appeared on the surface. This structure was related to the development of a (200) fiber texture in the BCC phase. Sodium propargyl sulfonate accelerates the discharge of nickel and inhibits the discharge of Fe.

The foil has many industrial applications in the area of memory devices for computers, laser components and precise instruments.

The paper presents a process to produce a foil with iron up to 64 wt. percent from a chloride‐sulfate based solution used in normal DC mode. The dependence of microstructure and surface morphology on iron contents also is presented. Until now, there has been little research or reports on this subject.

The corrosion behaviour of pulse plating nanocrystalline iron‐nickel‐chromium (Fe‐Ni‐Cr) alloys in acidic, alkaline and salt solutions has been studied. The corrosion resistance of nanocrystalline Fe‐Ni‐Cr alloys in various compositions and other nanocrystalline referred in literatures have been compared. The results reveal that the corrosion of Fe₆₉Ni₁₀Cr₂₀S alloy has dominant superiority over the other nanocrystalline materials.

Ultrasonic consolidation (UC) is a novel additive manufacturing process developed for fabrication of metallic parts from foils. While the process has been well demonstrated for part fabrication in Al alloy 3003, some of the potential strengths of the process have not been fully explored. One of them is its suitability for fabrication of parts in multi‐materials. This work aims to examine this aspect.

Multi‐material UC experiments were conducted using Al alloy 3003 foils as the bulk part material together with a number of engineering materials (foils of Al‐Cu alloy 2024, Ni‐base alloy Inconel 600^® AISI 347 stainless steel, and others). Deposit microstructures were studied to evaluate bonding between various materials.

It was found that most of the materials investigated can be successfully bonded to alloy Al 3003 and vice versa. SiC fibers and stainless wire meshes were successfully embedded in an Al 3003 matrix. The results suggest that the UC process is quite suitable for fabrication of multi‐material structures, including fiber‐reinforced metal matrix composites.

This work systematically examines the multi‐material capability of the UC process. The findings of this work lay a strong foundation for a wider and more efficient commercial utilization of the process.

The dramatic expansion in the use and capability of electronic devices in recent years has been facilitated by the substantial development of production techniques. Modern electronic circuits as used in the computer, defence, aerospace, vehicle and domestic appliance industries contain a great many joints and these have to be made reliably and economically without degrading sensitive circuit components. This article describes the major microjoining developments currently of interest to the microelectronics industry, with emphasis on the work conducted by the microjoining section of The Welding Institute, much of which has been directly sponsored by the UK Ministry of Defence (DCVD).

The purpose of this work is to provide theoretical guidance and experimental analysis for optimized cathodic protection (CP) design of low alloy steel in deep water environments.

In the present study, the CP criteria of 10Ni5CrMoV low alloy steel were investigated in a simulated deep water environment (350 m) regarding the theoretical protection potential and measured protection potential. The influences of hydrostatic pressure (HP) and temperature were also discussed in detail. The theoretical protection potential was analyzed with the Nernst equation, and the measured minimum protection potential was derived by extrapolating the Tafel portion of anodic polarization curves.

The results indicate that the minimum protection potential of low alloy steel shifts to a positive value in a deep-ocean environment. This can be attributed to the combined effects of HP and the temperature. Moreover, the temperature has a stronger influence compared with HP. The results suggest that the CP potential criteria used in shallow water are still applicable in the deep ocean, which is further confirmed through the SEM and x-ray diffraction analysis of the corrosion products resulted from the potentiostatic cathodic polarization experiments at −0.85 V_CSE.

In recent decades, successful applications of CP for long-term corrosion protection of the steel components applied at a subsea level have enabled the offshore industry to develop reliable and optimized CP systems for shallow water. However, differences in the seawater environment at greater depths have raised concerns regarding the applicability of the existing CP design for deeper water environments. Hence, this research focuses on the CP criteria of low alloy steel in simulated deep water environment concerning the theoretical protection potential and measured protection potential. The influences of HP and temperature were also discussed.

Today's and, to a greater extent, tomorrow's technologies in the Printed Circuit Industry need — besides very stringent challenges on quality — a very careful, precise and cost effective selection of valuable materials and sophisticated techniques in order to achieve optimal relationships between the costs and benefits of each technology. A survey of materials, their costs, technical requirements and also of alternative methods is given — today's and tomorrow's state‐of‐the‐art.

1. Zinc Zinc was closely linked with copper as a sacrificial partner and because of this relationship an increased use was found for the metal in the 19th century. Around 1838 particular interest was being shown by scientists in the protective power of zinc when in contact with other metals and articles indicate that a scientific appreciation of the principles involved was evident.

The corrosion inhibitive efficiencies of substituted dithiomalonamides have been determined at different concentrations for 304 SS in H3PO4‐HC1 mixture at 25°C using potentiostatic technique. The percentage inhibition efficiencies have been found to increase with increasing concentrations of inhibitors. 1,5‐Di‐p‐methylphenyl‐2,4‐Dithiomalonamide was found to be the most effective inhibitor followed by: 1,5‐Di‐p‐methoxyphenyl‐2,4‐Dithiomalonamide, 1,5‐Di‐phenyl‐2,4‐Dithiomalonamide, 1,5‐Di‐p‐cholorophenyl‐2,4‐Dithoimalonamide. Marked influence of the inhibitors is observed in decreasing the critical current density and enlarging the passive range.

This study aims to investigate the wetting behavior of AgCuTi and AgCu filler metals on selective laser melting (SLMed) Ti/TiB₂, and to analyze the microstructure and fracture characteristics of SLMed Ti/TiB₂/AgCuTi or AgCu alloy/SLMed Ti/TiB₂ brazed joints. The wetting behavior of AgCuTi and AgCu filler metals on the selective laser melted (SLMed) Ti/TiB₂ has been studied. The analysis of microstructures and fracture characteristics in vacuum-brazed SLMed Ti/TiB₂ substrate, using AgCuTi and AgCu filler metals, has been conducted to elucidate the influence of brazing temperature and alloy composition on the shear strength of the brazed joints.

Brazing SLMed-Ti/TiB₂ in a vacuum using AgCuTi and AgCu filler metals, this study aims to explore the optimal parameters for brazed joints at various brazing temperatures (800°C−950°C).

The findings suggest that elevated brazing temperatures lead to a more extensive diffusion region in the joint as a result of the partial melting of the filler metal. The joint composition changes from distinct Ti₂Cu layer/TiCu layer/filler metal to a-Ti (ss) + ß-Ti (ss)/TiCu. As the brazing temperature increases, the fracture mode shifts from brittle cleavage to ductile fracture, mainly attributed to a decrease in the CuTi within the brazed joint. This change in fracture behavior indicates an improvement in the ductility and toughness of the joint.

The originality of this study lies in the comprehensive analysis of the microstructure and shear strength of vacuum brazing SLMed Ti/TiB₂ using AgCuTi and AgCu filler metals.

Pitting inhibition efficiency of SO₄⁻ and NO₃⁻ on AISI 316L stainless steel in contact with Cl⁻-containing fiber dyeing solutions together with the influence of the anions on absorption behavior of the solutions were investigated. The purpose of the study is to experimentally determine an optimized dyeing solution efficient on both – inhibition of the steel’s pitting and exhaustion of the dyes dissolved.

Methods such as electrochemical cyclic polarization, UV-visible range spectrophotometry and scanning electron microscopy have been used to assess the performance of two inhibitors on both pitting inhibition of the steel and dissolving ability over the reactive dyes. To find out a promising dyeing solution mixture in both aspects, Cl content of the original dyeing solution was replaced gradually with the inhibiting anions, where the total anionic content was kept constant to unchange the dye exhaustion potential of the solution. Then, those solutions came out with diverse pitting inhibition, and dye absorption levels were compared together for reducing/avoiding the pitting issues of the reactive dyeing vessels of the industry.

Rather high absorption levels detected by visible range spectrophotometry on the solutions showing sound inhibition levels indicated possibility of unaltered reactive dyeing qualities with an enhanced vessel lifetime as the inhibitive anions replace Cl⁻. Nitrate performed better than sulfate both on inhibition and absorption in the dyeing solutions. Also, 316L vessels became open to an extra anodic protection in inhibitor added solutions.

The findings are valid for a certain group of reactive dyes and dyeing solutions held at 70°C. However, the testing methods are available to almost any dyeing solution and dyeing temperature.

The work presents a combined testing of pitting inhibition and absorption behavior of dyeing solutions involving Cl⁻ that has not been reported so far. It shows that solution recipes least harmful to the steel vessels can be outlined for various reactive or other types of dye groups.