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Article
Publication date: 28 October 2019

Xiaoqing Ni, Liang Zhang, Wenheng Wu, Dexiang Zhu, Decheng Kong, Chaofang Dong and Guoliang Zhu

Laser melting deposition (LMD) is an advanced additive manufacturing (AM) technology without powder waste, and nickel-based alloys with different Nb contents were created…

Abstract

Purpose

Laser melting deposition (LMD) is an advanced additive manufacturing (AM) technology without powder waste, and nickel-based alloys with different Nb contents were created one-time by adjusting the ratio of mixed powders via a dual-feed system. Here, the authors provide a systematic report on the effects of the Nb content on the microstructure, Laves phase segregation and mechanical properties of as-received LMD nickel-based alloys. The effects of the Nb content on the microstructure, precipitation evolution and mechanical properties of the subsequent heat-treated LMD samples are also discussed in this paper.

Design/methodology/approach

Thus, the present research aims to obtain a better understanding of the effect of Nb content on the microstructural and mechanical properties of the as-received LMD Inconel 718 alloys through high-throughput sample fabrication. The microstructures were characterized by scanning electron microscopy and energy-dispersive spectroscopy, electron back-scattered diffraction and transmission electron microscopy methods. The mechanical properties were obtained from compressive tests and nano-indentation tests. Electrochemical tests, including electrochemical impedance spectroscopy and potentiodynamic polarizations, were carried out to evaluate the durability of the Inconel 718 alloys. Results can provide a factual basis for future applications of the functionally graded by AM technology.

Findings

The grain size of the as-received LMD Inconel 718 alloys decreased with the Nb content. The Laves phase distribution at the macro level was relatively uniform and the Laves phase exhibited a 1.5-fold nano-hardness compared with the matrix. The strength improvement for the as-received LMD Inconel 718 alloys with Nb content was attributed to grain refinement and enhancement of the Laves phase in terms of both hardness and content. Meanwhile, the corrosion resistance increased with the increase of the Nb content, especially for the pitting potential, which was attributed to the optimization of carbide precipitates due to the strong affinity between niobium and carbon.

Originality/value

The results provide a factual basis for the Nb content effect in LMD nickel-based alloys, and this method can greatly promote the development of new materials. The authors believe that this study makes a significant contribution to the literature and is suitable for publication.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 11 January 2022

Tushar Sonar, Visvalingam Balasubramanian, Sudersanan Malarvizhi, Thiruvenkatam Venkateswaran and Dhenuvakonda Sivakumar

The primary objective of this investigation is to optimize the constricted arc tungsten inert gas (CA-TIG) welding parameters specifically welding current (WC), arc…

Abstract

Purpose

The primary objective of this investigation is to optimize the constricted arc tungsten inert gas (CA-TIG) welding parameters specifically welding current (WC), arc constriction current (ACC), ACC frequency (ACCF) and CA traverse speed to maximize the tensile properties of thin Inconel 718 sheets (2 mm thick) using a statistical technique of response surface methodology and desirability function for gas turbine engine applications.

Design/methodology/approach

The four factor – five level central composite design (4 × 5 – CCD) matrix pertaining to the minimum number of experiments was chosen in this investigation for designing the experimental matrix. The techniques of numerical and graphical optimization were used to find the optimal conditions of CA-TIG welding parameters.

Findings

The thin sheets of Inconel 718 (2 mm thick) can be welded successfully using CA-TIG welding process without any defects. The joints welded using optimized conditions of CA-TIG welding parameters showed maximum of 99.20%, 94.45% and 73.5% of base metal tensile strength, yield strength and elongation.

Originality/value

The joints made using optimized CA-TIG welding parameters disclosed 99.20% joint efficiency which is comparatively 20%–30% superior than conventional TIG welding process and comparable to costly electron beam welding and laser beam welding processes. The parametric mathematical equations were designed to predict the tensile properties of Inconel 718 joints accurately with a confidence level of 95% and less than 4.5% error. The mathematical relationships were also developed to predict the tensile properties of joints from the grain size (secondary dendritic arm spacing-SDAS) of fusion zone microstructure.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 5
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 16 October 2020

Sahil Sharma, Umesh Kumar Vates and Amit Bansal

In the current exploration, the machinability of three different nickel-based super-alloy materials (Inconel 625, Inconel 718 and Nimonic 90) was experimentally…

Abstract

Purpose

In the current exploration, the machinability of three different nickel-based super-alloy materials (Inconel 625, Inconel 718 and Nimonic 90) was experimentally investigated by using a die-sinking electrical discharge machining (EDM). The effect of changing important input process parameters such as pulse on time (Ton), off time (Toff), peak current (Ip) and tool rotation (TR) was investigated to get optimum machining characteristics such as material removal rate, roughness, electrode wear rate and overcut.

Design/methodology/approach

Experimentation has been performed by using Taguchi L9 orthogonal design. An integrated route of fuzzy and grey relational analysis approach with Taguchi’s philosophy has been intended for the simultaneous optimization of machining output parameters.

Findings

The most approbatory factors for machining setting have been attained as: (Ton = 100 µs, Toff = 25 µs, Ip = 14 A, TR = 725 rpm) for machining of Inconel 625 and Inconel 718; and (Ton = 100 µs, Toff = 75 µs, Ip = 14 A, TR = 925 rpm) for machining of the Nimonic 90 material. Peak current has been observed as an overall influencing factor to achieve better machining process. Microstructural study through SEM has also been carried out to figure out the surface morphology for the EDMed Ni-based super alloys.

Originality/value

The proposed machining variables and methodology has never been presented for Nimonic 90 alloy on die-sinking EDM.

Details

World Journal of Engineering, vol. 18 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 April 2001

R.J. Smith, G.J. Lewi and D.H. Yates

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…

3387

Abstract

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.

Details

Aircraft Engineering and Aerospace Technology, vol. 73 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 June 1998

Kurt P. Rohrbach

Guidelines for making a wise choice when selecting high temperature alloys are provided. Four groups of alloys are discussed, along with helpful selection criteria…

1012

Abstract

Guidelines for making a wise choice when selecting high temperature alloys are provided. Four groups of alloys are discussed, along with helpful selection criteria. Substantial benefits accrue from contemporary alloy manufacturing techniques. Process databases and state‐of‐the‐art forging equipment significantly impact product quality, consistency and cost effectiveness. Finally, the author suggests that the elimination of unnecessary test requirements offers potential for savings in time and money. He feels that alloy integrity can be assured by any producer who can demonstrate narrow limits of compositional control, as well as melting, remelting and hot working controls.

Details

Aircraft Engineering and Aerospace Technology, vol. 70 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 17 November 2021

Monika Duchna, Iwona Cieślik, Alexander Kloshek, Bogusława Adamczyk-Cieślak, Magdalena Zieniuk, Dorota Moszczyńska and Jarosław Mizera

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

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Rapid Prototyping Journal, vol. 28 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 12 November 2020

Sahil Sharma, Umesh Kumar Vates and Amit Bansal

In the current exploration, the machining of a Nimonic 90 superalloy material was carried out in a die-sinking electric discharge machine. Experimentation was performed to…

Abstract

Purpose

In the current exploration, the machining of a Nimonic 90 superalloy material was carried out in a die-sinking electric discharge machine. Experimentation was performed to investigate the impact of three input machining factors – current (I), pulse on time (Ton) and pulse off time (Toff) – on various response characteristics such as material removal rate (MRR), surface roughness (Ra) and electrode wear rate (EWR).

Design/methodology/approach

A Taguchi L9 design and ANOVA were used to assess machine response characteristics. The study also involved a grey relational analysis (GRA) multi-objective technique of optimization.

Findings

For single-objective performance, the most appropriate machining factors for achieving the best performance were attained as: MRR (I = 20 A, Ton = 200 µs and Toff = 45 µs), Ra (I = 14 A, Ton = 100 µs and Toff = 25 µs) and EWR (I = 17 A, Ton = 150 µs and Toff = 45 µs). The proposed grey relational approach provided the optimal settings (i.e. 14 A I, 100 µs Ton and 25 µs Toff) for the variables used to calculate the predicted and experimental results. Also, a confirmation test indicated that the final experimental grey relational grade value was enhanced when the experimentation was performed at optimal setting.

Originality/value

To the best of the authors’ knowledge, the present work is the first to examine the proposed machining variables (i.e. current, pulse on time and pulse off time) in relation to the optimization technique of GRA for a Nimonic 90 alloy using a die-sinking electric discharge machining method.

Details

World Journal of Engineering, vol. 18 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 June 1965

S.W. Hallwood and P.B. Wallis

An Assessment of the Temperature Environment likely to be Experienced by Hypersonic Aircraft, Type of Structure Suitable for Use in this Environment and a Detailed Review…

Abstract

An Assessment of the Temperature Environment likely to be Experienced by Hypersonic Aircraft, Type of Structure Suitable for Use in this Environment and a Detailed Review of the Properties of Nickel Base Alloys, Including their Manufacture and Fabrication, for Structural Use. THE demand for faster and yet faster air‐craft has continued unabated since the Wright Brothers made their first tentative flights some sixty years ago. In 1947 the sound barrier was broken for the first time by the Bell XI. and with the design and development of the Concorde and the American S.S.T. the first stages of breaking the heat barrier have been taken. The next generation of aircraft will be required to fly even faster, and it has been suggested that flight at hypersonic speeds, i.e. Mach 5 and above, will be the next step.

Details

Aircraft Engineering and Aerospace Technology, vol. 37 no. 6
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 July 1989

Lawrence Kline and Michael Lawler

ANY discussion of high‐performance fasteners must first define the term because the requirements for “high performance” can vary with the application.

Abstract

ANY discussion of high‐performance fasteners must first define the term because the requirements for “high performance” can vary with the application.

Details

Aircraft Engineering and Aerospace Technology, vol. 61 no. 7
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 22 August 2017

Bo Chen and Jyoti Mazumder

The aim of this research is to study the influence of laser additive manufacturing process parameters on the deposit formation characteristics of Inconel 718 superalloy…

Abstract

Purpose

The aim of this research is to study the influence of laser additive manufacturing process parameters on the deposit formation characteristics of Inconel 718 superalloy, the main parameters that influence the forming characteristics, the cooling rate and the microstructure were studied.

Design/methodology/approach

Orthogonal experiment design method was used to obtain different deposit shape and microstructure using different process parameters by multiple layers deposition. The relationship between the processing parameters and the geometry of the cladding was analyzed, and the dominant parameters that influenced the cladding width and height were identified. The cooling rates of different forming conditions were obtained by the secondary dendrite arm spacing (SDAS).

Findings

The microstructure showed different characteristics at different parts of the deposit. Cooling rate of different samples were obtained and compared by using the SDAS, and the influence of the process parameters to the cooling rate was analyzed. Finally, micro-hardness tests were done, and the results were found to be in accordance with the micro-structure distribution.

Originality/value

Relationships between processing parameters and the forming characteristics and the cooling rates were obtained. The results obtained in this paper will help to understand the relationship between the process parameters and the forming quality of the additive manufacturing process, so as to obtain the desired forming quality by appropriate parameters.

Details

Rapid Prototyping Journal, vol. 23 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

1 – 10 of 427