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This paper aims to develop an electrochemical abrasive jet machining (ECAJM) technology to investigate the surface machining effect of Ti-6Al-4V alloy.

First, the ECAJM equipment was set up, and a series of experiments for the surface machining of Ti-6Al-4V alloy was performed.

The experimental results show that the flowing abrasives of 0.05 Wt.% can effectively remove the TiO₂ oxide film of Ti-6Al-4V alloy surface. In addition, the flowing abrasives produce cutting machining effect on the surface of titanium aluminum alloy, and the oxide film can be removed effectively. For the case of machining pressure of 0.4 Mpa and machining gap of 0.4 mm, the processing efficiency can be achieved up to 20 µm/s.

Under different machining pressure, the flowing abrasive with high kinetic energy impacting the Ti-6Al-4V alloy surface and the oxide film produced from the electrolytic reaction process can be removed effectively, thereby enhancing the efficiency of electrochemical machining process.

This study aims to apply an electrochemical grinding (ECG) technology to improve the material removal rate (MRR) under the premise of certain surface roughness in machining U71Mn alloy.

The effects of machining parameters (electrolyte type, grinding wheel granularity, applied voltage, grinding wheel speed and machining time) on the MRR and surface roughness are investigated with experiments.

The experiment results show that an electroplated diamond grinding wheel of 46# and 15 Wt.% NaNO₃ + 10 Wt.% NaCl electrolyte is more suitable to be applied in U71Mn ECG. And the MRR and surface roughness are affected by machining parameters such as applied voltage, grinding wheel speed and machining time. In addition, the maximum MRR of 0.194 g/min is obtained with the 15 Wt.% NaCl electrolyte, 17 V applied voltage, 1,500 rpm grinding wheel speed and 60 s machining time. The minimum surface roughness of Ra 0.312 µm is obtained by the 15 Wt.% NaNO₃ + 10 Wt.% NaCl electrolyte, 13 V applied voltage, 2,000 rpm grinding wheel speed and 60 s machining time.

Under the electrolyte scouring effect, the products and the heat generated in the machining can be better discharged. ECG has the potential to improve MRR and reduce surface roughness in machining U71Mn.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2023-0341/

The purpose of this study is analysis of deformation and vibrations of turbine blades produced by high electrolyte pressure during electrochemical machining.

An experimental setup was designed, experiments were conducted and the obtained results were compared with the finite element results. The deformations were measured according to various flow rates of electrolyte. In finite element calculations, the pressure distribution created by the electrolyte on the blade surface was obtained in the ANSYS® (A finite element analysis software) Fluent software and transferred to the static structural where the deformation analysis was carried out. Three different parameters were examined, namely blade thickness, blade material and electrolyte pressure on blade disk caused by mass flow rate. The deformation results were compared with the gap distances between cathode and anode.

Large deformations were obtained at the free end of the blade and the most curved part of it. The appropriate pressure values for the electrolyte to be used in the production of blisk blades were proposed numerically. It has been determined that high pressure applications are not suitable for gap distance lower than 0.5 mm.

When the literature is examined, it is required that the high speed flow of the electrolyte is desired in order to remove the parts that are separated from the anode from the machining area during electrochemical machining. However, the electrolyte flowing at high speeds causes high pressure in the blisk blades, excessive deformation and vibration of the machined part, and as a result, contact of the anode with the cathode. This study provides important findings for smooth electro chemical machining at high electrolyte flows.

DIFFICULT to machine, high temperature materials have been introduced at an ever increasing rate into aircraft propulsion systems over the last twenty five years. Over the same period, the aircraft industry has had an ‘on‐off’ affair with electrochemical machining (ECM).

ON October 15, Lord Polwarth, Chairman of the Executive Committee of the Scottish Council (Development and Industry), officially opened a new extension to the Barmax Works of Crow, Hamilton and Co. Ltd. in Haggs Road, Pollokshields, Glasgow. On display at this ceremony were two machines of considerable interest to the aero engine industry. The first was an automatic ultrasonic flaw detector which has been designed for the purpose of examining aircraft gas turbine compressor disks for interna! flaws, while the second was an electro‐chemical metal forming machine for the production of gas turbine blades. We are concerned here with the second of these two machines.

The purpose of this paper is to study the functionality of additively manufactured (AM) parts, mainly depending on their dimensional accuracy and surface finish. However, the products manufactured using AM usually suffer from defects like roughness or uneven surfaces. This paper discusses the various surface quality improvement techniques, including how to reduce surface defects, surface roughness and dimensional accuracy of AM parts.

There are many different types of popular AM methods. Unfortunately, these AM methods are susceptible to different kinds of surface defects in the product. As a result, pre- and postprocessing efforts and control of various AM process parameters are needed to improve the surface quality and reduce surface roughness.

In this paper, the various surface quality improvement methods are categorized based on the type of materials, working principles of AM and types of finishing processes. They have been divided into chemical, thermal, mechanical and hybrid-based categories.

The review has evaluated the possibility of various surface finishing methods for enhancing the surface quality of AM parts. It has also discussed the research perspective of these methods for surface finishing of AM parts at micro- to nanolevel surface roughness and better dimensional accuracy.

This paper represents a comprehensive review of surface quality improvement methods for both metals and polymer-based AM parts.

The purpose of this paper is to exploit the fullest potential and capability of different non-traditional machining (NTM) processes, it is often recommended to operate them at their optimal parametric combinations. There are several mathematical tools and techniques that have been effectively deployed for identifying the optimal parametric mixes for the NTM processes. Amongst them, grey relational analysis (GRA) has become quite popular due to its sound mathematical basis, ease to implement and apprehensiveness for multi-objective optimization of NTM processes.

In this paper, GRA is integrated with fuzzy logic to present an efficient technique for multi-objective optimization of three NTM processes (i.e. abrasive water-jet machining, electrochemical machining and ultrasonic machining) while identifying their best parametric settings for enhanced machining performance.

The derived results are validated with respect to technique for order preference by similarity to ideal solution (TOPSIS), and analysis of variance is also performed so as to identify the most significant control parameters in the considered NTM processes.

This grey-fuzzy logic approach provides better parametric combinations for all the three NTM processes with respect to the predicted grey-fuzzy relational grades (GFRG). The developed surface plots help the process engineers to investigate the effects of various NTM process parameters on the predicted GFRG values.

The adopted approach can be applied to various machining (both conventional and non-conventional) processes for their parametric optimization for achieving better response values.

The purpose of this paper is to demonstrate the use of selective laser melting for producing single and double chamber laser cutting nozzles. The main aim is to assess a whole production chain composed of an additive manufacturing (AM) and consecutive finishing processes together. Beyond the metrological and flow-related characterization of the produced nozzles, functional analysis on the use of the produced nozzles are carried out through laser cutting experiments.

SLM experiments were carried out to determine the correct compensation factor to achieve a desired nozzle diameter on steel with known processibility by SLM and using standard nozzle geometries for comparative purposes. The produced nozzles are finished through electrochemical machining (ECM) and abrasive flow machining (AFM). The performance of nozzles produced via additive manufacturing (AM) are compared to conventional ones on an industrial laser cutting system through cutting experiments with a 6 kW fibre laser. The produced nozzles are characterized in terms of pressure drop and flow dynamics through Schlieren imaging.

The manufacturing chain was regulated to achieve 1 mm diameter nozzles after consecutive post processing. The average surface roughness could be lowered by approximately 80 per cent. The SLM produced single chamber nozzles would perform similarly to conventional nozzles during the laser cutting of 1 mm mild steel with nitrogen. The double chamber nozzles could provide complete cuts with oxygen on 5 mm-thick mild steel only after post-processing. Post-processing operations proved to decrease the pressure drop of the nozzles. Schlieren images showed jet constriction at the nozzle outlet on the as-built nozzles.

In this work, the use of an additive manufacturing process is assessed together with suitable finishing and functional analysis of the related application to provide a complete production and evaluation chain. The results show how the finishing processes should be allocated in an AM-based production chain in a broader vision. In particular, the results confirm the functionality for designing more complex nozzle geometries for laser cutting, exploiting the flexibility of SLM process.

As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

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 (T_on), off time (T_off), 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.

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.

The most approbatory factors for machining setting have been attained as: (T_on = 100 µs, T_off = 25 µs, Ip = 14 A, TR = 725 rpm) for machining of Inconel 625 and Inconel 718; and (T_on = 100 µs, T_off = 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.

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