Multiphysics Simulation of the Material Removal in Jet Electrochemical Machining

Abstract

Jet Electrochemical Machining (Jet-ECM) is a technology for quickly and flexibly generating micro structures and micro geometries in metallic parts independently from the material's hardness and without any thermal or mechanical impact [1]. In the process no tool wear occurs and the machined surface is very smooth [2]. The Jet-ECM process strongly depends on the shape of the electrolyte jet. In a previous study Hackert [3] built a numerical model with COMSOL Multiphysics based on a predefined jet shape. The simulated dissolution results of this model progressively differ from experimental results with increasing processing time. Hence, a multiphysics model which integrated fluid dynamics using the level set method for two-phase flow was created. Furthermore, in the present study the electric boundary resistance at the interface of workpiece and electrolyte is considered. According to the real Jet-ECM process the simulation is divided into two steps. In the first simulation step the jet is formed, and in the second simulation step the anodic dissolution is simulated by deforming the geometry. The dynamic behavior of the electrolyte jet could be simulated during the material removal process. So effects became visible which affect the machining results.

A review of physical experimental research in jet electrochemical machining

“…At the electrolyte-anode boundary, the base metal reacts with the hydroxide ions to produce a metal hydroxide (3) which can be carried away from the workpiece. The dissolution process continues in this continuous cycle.…”

“…Although the concept of Jet-ECM first appeared in the 1980s [2], the rate of research and development has accelerated in the twenty-first century, both in physical experimentation and in modelling and simulation of the process, for example, simulation of material removal [3] and energy distribution modulation [4]. Jet-ECM has become an attractive area of research due to its benefits over both Thomas Kendall thomas.kendall@manchester.ac.uk 1 School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester, UK 2 Blueacre Technology Ltd., Dundalk, Co Louth, Ireland 3 School of Engineering, Manchester Metropolitan University, Manchester, UK traditional and alternative electrochemical processes due to its ability to machine micro-size features regardless of material hardness, without producing heat-affected zones, surface stresses, micro cracks and burrs at good energy efficiency [5]. These characteristics lend Jet-ECM to several manufacturing sectors, including but not exclusive to aerospace, micro-electronics, medical and biomedical applications.…”

The Effect of Electrolytic Jet Orientation on Machining Characteristics in Jet Electrochemical Machining

“…Different micro-scale features were fabricated in this study. For micro-dimples, the applied voltage was in the range of from 6 V to 28 V, with an increment of 2 V, and the machining time for each micro-dimple was 15 s. Researchers chose larger voltages in related studies [24,25], but we selected a smaller electric voltage because the inner diameter of the nozzle and working gap was small. For micro-perforations, the applied voltage was 10 V, and the machining time for each perforation was also 15 s. For the micro-grooves fabricated with the translating machining, the applied voltage ranged from 10 V to 30 V, with an increment of 4 V, and the translating speed was 200 μm/s.…”

Modelling and simulation of ultrasonic-assisted jet electrochemical micro drilling process

“…Hackert-Oschatzchen et al. 8–11 documented several research artefacts describing the shape, nature and capability of electrolyte jet and their influence on the machining performances in Jet-ECM process using COMSOL multi-physics simulation software and optimization techniques. They introduced a continuous electrolyte free Jet-ECM prototype to produce micro geometries and verified the same using COMSOL.…”

“…10 Further adding to that, they also created a multi-physics model integrating fluid dynamics with electrodynamics and deformed geometry as various physics-based interfaces and simulated the material removal by the Jet-ECM process. 11 They divided the simulation into two steps: the first being the jet initialization and second being the material removal.…”