Experimental and analytical investigations into wire electrochemical micro turning

This article gives classification of micromanufacturing in general and micromachining processes in particular. For different micromachining processes, one can have different kinds of operations through which different features, shapes, accuracy, precision, and dimensions can be achieved. This article as Part I reports an overview of only three processes as diamond turn machining (a class of traditional micromachining processes), electrochemical micromachining, and focused-ion-beam micromachining (a class of advanced micromachining processes). About all these three processes, a brief introduction to the mechanisms of material removal is reported followed by the new developments in each process which are discussed independently. In various sections, some areas where research work needs to be done are identified and very briefly discussed.

Section: Electrochemical Micromachiningmentioning

confidence: 99%

Micromachining: An overview (Part I)

Jain

Balasubramaniam

Mote

et al. 2020

“…In the field of micromanufacturing, several advancements have been achieved by exploiting the negligible cutting forces and stresses involved in non-conventional machining. In the past decade, several researchers have worked towards non-conventional micromanufacturing by considering techniques such as hybrid wire electric discharge machining (WEDM) 1 , hybrid electric discharge machining (EDM) 2 and electric discharge wire cutting 3 . WEDM is a variant of EDM which uses controlled and repetitive spark erosions for material removal.…”

Section: Introductionmentioning

confidence: 99%

Image processing algorithm for detection, quantification and classification of microdefects in wire electric discharge machined precision finish cut surfaces

Abhilash

Chakradhar

2021

This study aims to create an image processing algorithm that categorises the wire electric discharge machine (WEDM) processed finish cut surfaces, based on surface microdefects. The algorithm also detects the defect locations and suggests alternate parameter settings for improving the surface integrity. The proposed automated analysis is more precise, efficient and repeatable compared to manual inspection. Also, the method can be used for automatic data generation to suggest parameter changes in closed loop systems. During the training phase, mean, standard deviation and defect area fraction of enhanced binary images are extracted and stored. The training dataset consists of 27 WEDM finish cut surface images with labels, ‘coarse’, ‘average’ and ‘smooth’. The trained model is capable of categorising any machined surface by detecting the microdefects. If the machined surface image is not classified as a smooth image, then alternate input parameter settings will be suggested by the model to minimise the microdefects. This is done based on the Euclidean distance between the current image datapoint and the nearest ‘smooth’ class datapoint.

“…(b) Micro-grooves on copper rod of 5 mm. (c) Micro-grooves on Ti6Al4V rod of 5 mm.Source: Sharma et al24 , Chen et al61 and Tyagi et al65…”

mentioning

confidence: 99%

Micro-machining: An overview (Part II)

Jain

Patel

Ramkumar

et al. 2021

Self Cite

This article on ‘Micro-machining: An Overview (Part II)’ is in continuation to ‘Micro-machining: An Overview (Part I)’ published in this journal ( Journal of Micromanufacturing). It consists of four parts, namely, electrochemical micro-texturing, electrochemical spark micro-machining, molecular dynamics simulation and sustainability issues of micro-machining processes. Electrochemical micro-texturing (ECMTex) deals with various techniques developed for micro-texturing on different types of workpiece-surfaces, namely, flat, curved and free-form surfaces. Here, basically two categories of techniques have been reviewed, namely, with mask and without mask. It also deals with ‘single point tool micro-texturing’ which turns out to be a single-step technique requiring minimum time, but the accuracy and repeatability obtained after micro-texturing need to be critically analysed. For mass production, one needs to go for sinking kind of ECMTex processes. Electrochemical spark micro-machining (ECSMM) is an interesting hybrid (ECM+EDM) process which can be applied for electrically conducting as well as electrically non-conducting materials. However, the work reported in this article deals only with the electrically non-conducting materials for which this process was initially developed. This process has a lot of potential for theoretical work to be done. In this article, two theories of sparking/discharging have been briefly mentioned: single bubble discharging/sparking and single surface discharging. It also dicusses its applications for different types of electrically non-conducting materials. Molecular dynamics simulation (MDS) of micro-/nano-machining processes is very important, but it is very cumbersome to understand at atomic/molecular scale. In these processes, the material behaviour at micro-/nano-level machining is completely different as compared to bulk-machining (macro-machining) processes. Hence, some fundamentals of MDS have been discussed. It just gives the idea of available techniques, softwares and models for different types of processes. However, there is the need of further research work to be done for clearly understanding the MDS of micro-/nano-machining. In the end, the sustainability of micro-machining issues have been discussed, mainly based on the energy consumption per unit mass of production. It is concluded that the advanced micro-manufacturing processes are highly energy-intensive processes, and they need further studies to be done for making them more suitable from sustainability point of view. At the end of each section, some potential areas of research for enhancing the accuracy and repeatability, and minimising the production time of each process have been discussed.