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THE wide range of creep resistant nickel‐base alloys now available has been developed primarily for use at elevated temperatures in the gas turbine engine. These products replaced the Cr.Ni. stainless steels used at high temperatures in the very early days of gas turbine development. Early work in the UK led to the introduction of the NIMONIC series of alloys. The first, NIMONIC alloy 75, was used by Whittle more than 30 years ago and was one of the alloys that made the gas turbine engine a practical proposition.

Since the development of the Nimonic¹ alloys for Sir Frank Whittle’s first jet engine, Henry Wiggin Ltd, now part of Special Metals Corporation, has been involved with the design and improvement of nickel alloys for aerospace engineering. Whilst much of this work continues to be in relation to alloys for the high strength/high temperature applications of turbine blades, discs, seals, rings and casings of aero engines, nickel alloys are being utilised for other key aerospace engineering areas such as tooling for composite manufacture. The focus of this paper is on four recent developments in nickel alloys for aerospace engineering, namely: disc alloys; low expansion superalloys; Inconel alloy 718SPF – a nickel base superalloy capable of being superplastically formed; Nilo (low expansion alloys) for composite tooling.

Considers the advantages of highly alloyed stainless steel such as duplex stainless steels or nickel‐based alloys in highly corrosive environments. Looks at corrosion rates for alloys in acetic acid and presents results of tests on the influence of contaminants in the acid. Gives practical applications. Concludes that duplex stainless steels demonstrate higher corrosion resistance than austenitic stainless steels and are often comparable to nickel base alloys.

The influence of variables such as temperature, agitation, oxygenation on the corrosion of aluminium, copper, nickel base alloys in 3% NaCI solution has been studied by electrochemical and weight loss measurements. It has been observed that the corrosion process is under cathodic control for all the alloys studied. Some nickel and aluminium base alloys merit consideration as a substitute for ferrous alloys in salt water under conditions similar to those reported in this paper.

NOW in full production at the Glossop, Derbyshire, plant of Union Carbide Ltd. is a vacuum melting plant originally opened at the end of last year. A comprehensive range of vacuum‐melted nickel base alloys and maraging steels is now being produced by the plant—the range being known as UCAR Superalloys.

This paper aims to identify the optimal forming angle for the selective laser melting (SLM) process and evaluate the mechanical properties of the SLM-formed GH3536 alloy in the aero-engine field.

Forming the samples with optimized parameters and analyzing the microstructure and properties of the block samples in different forming angles with scanning electron microscope, XRD, etc. so as to analyze and reveal the laws and mechanism of the block samples in different forming angles by SLM.

There are few cracks on the construction surface of SLM formed samples, and the microstructure shows columnar subgrains and cellular subgrains. The segregation of metal elements was not observed in the microstructure. The pattern shows strong texture strength on the (111) crystal plane. In the sample, the tensile strength of 60° sample is the highest, the plasticity of 90° forming sample is the best, the comprehensive property of 45° sample is the best and the fracture mode is plastic fracture. The comprehensive performance of the part is the best under the forming angle of 45°. To ensure the part size, performance and support structure processing, additional dimensions are added to the part structure.

In this paper, how to make samples with different forming angles is described. Combined with the standard of forged GH3536 alloy, the microstructure and properties of the samples are analyzed, and the optimal forming angle is obtained.

The purpose of this paper is to obtain high-temperature-resistant material with high density and to conduct microstructural investigations of 3D-printed Ni-based alloy 713C specimens.

High-density specimens of Ni-based alloy 713C were obtained by the optimizing selective laser melting (SLM) process parameters and an X-ray diffraction (XRD) analysis confirmed the occurrence of γ and γ′ phases and the presence of carbides in the SLM-manufactured Ni-based alloy 713C. The analysis of electron backscatter diffraction (EBSD) studies suggested a preferred 〈100〉 direction orientation and low angle misorientation for the SLM specimens.

The high-density specimens of Ni-based alloy 713C were obtained by the optimized SLM process parameters. XRD analysis confirmed the presence of γ and γ′ phases and carbides in the SLM-manufactured Ni-based alloy 713C. Analysis of EBSD studies suggested a preferred 〈100〉 direction orientation and low angle misorientation for the SLM specimen.

In this study, 3D-printed Ni-based alloy 713C with a high density of 99% was obtained for the first time, to the best of the authors’ knowledge.

Whilst it may be possible to produce alloys possessing a very high degree of resistance to corrosion, frequently they are deficient in mechanical or physical properties. Alternatively, the difficulties encountered in manufacture, or the prohibitive cost of materials, preclude their wide industrial application. By suitably varying the alloying additions to a very small number of basic metals a wide range of alloys can be produced, which not only possess good corrosion resistance but are also endowed with strength, ductility, hardness and wear‐resistance, etc.

This study aims to focus on experimenting the performance of aluminum (Al) powder mixed electric discharge machining (PMEDM) of two different materials viz plastic mould die steel (AISI P20) and nickel-based super alloy (Nimonic 75). This experimental study also focuses on using three different tool materials such as copper, brass and tungsten to analyze their influence on the process output. These materials find many uses in industrial as well as aerospace applications. The performance measures considered in this work are material removal rate (MRR), tool wear rate (TWR) and surface roughness (SR).

The experimental design used in this work is based on Taguchi’s L18 orthogonal array. Besides considering work and tool material as one of the process variables, other process variables are peak current (I_p), pulse on time (T_on) and concentration of powder (C_p). The analysis of variance (ANOVA) is performed on the experimental data to determine the significant variables that influence the output.

It is found that copper produced maximum MRR and brass tool exhibited higher TWR. However, the surface finish of the machined work piece was very much improved by using the brass tool. Though the performance of tungsten tool lies between the above two tool materials, it showed very little wear during EDM with or without the addition of Al powder.

The experimental investigation of PMEDM of nickel-based super alloy (Nimonic 75) has not been attempted before. Besides that, the study on the influence of tungsten tool on the performance of EDM is also very limited.

This paper aims to analyze the corrosion behavior in Ringer solution of six commercially used Ni-based alloys that are present and commonly used as metallic biomaterials.

The specimens were received in the form of cylindrical ingots and were cut to get five samples of each brand with a cylindrical shape of 2 mm height to conduct the study. In this scientific research, the following techniques were used: open circuit potential, potentiodynamic polarization studies, and electrochemical impedance spectroscopy.

The study findings revealed the passivation tendency of the different specimens. Additionally, when the materials were compared, it was discovered that the decisive factor for high corrosion resistance was the chromium concentration. However, with similar chromium content, the stronger concentration in molybdenum increased the resistance. According to the results obtained in this investigation, the biological safety of the dental materials studied in Ringer solution was considered very high for specimens 1 and 2, and adequate for the other samples.

Metal alloys used as biomaterials in contact with the human body should be deeply investigated to make sure they are biocompatible and do not cause any harm. The corrosion resistance of an alloy is the most important characteristic for its biological safety, as all problems arise because of the corrosion process. There is scarce investigation in these Ni-based dental biomaterials, and none found in these commercially used dental materials in Ringer solution.