Study on surface integrity and Cu-Al2O3 electrode wear behavior in ultrasonic-assisted electric arc machining of Inconel 718
Year: 2026
Type: article
Abstract: Inconel 718 nickel-based superalloy exhibits high strength, high toughness, low thermal conductivity, and a strong work-hardening tendency, which often lead to high cutting temperatures, severe tool wear, and poor surface integrity control during conventional machining. Electric arc machining (EAM), as a high-energy-density and non-contact material removal method, provides an efficient route for processing Inconel 718. However, non-uniform tool electrode wear, localized arc channel concentration, and insufficient removal of molten products still affect surface quality and process stability. To further improve EAM performance, axial ultrasonic vibration was introduced into a Cu-Al 2 O 3 tool electrode to establish an ultrasonic-assisted electric arc machining (UEAM) process. The effects of ultrasonic output level on surface morphology, cross-sectional thermal damage, elemental distribution, discharge behavior, and electrode wear were investigated. The results show that UEAM effectively weakens fish-scale textures, molten accumulation. With increasing ultrasonic output, Sa decreased from 15.35 μm to 8.90 μm, while the heat-affected zone thickness decreased from 117.15 μm to 21.79 μm. At 100% ultrasonic output, the recast layer thickness was reduced to 5.29 μm. EDS results showed that the surface O content decreased from 7.30 wt.% to 5.19 wt.%, indicating reduced oxygen enrichment. Electrical signal analysis revealed that ultrasonic vibration redistributed discharge energy and reduced abnormal high-current pulses. Meanwhile, electrode edge rounding, discharge craters, adhered debris were alleviated, and the relative electrode wear rate decreased from 23.03% to 16.65%. These results show that axial ultrasonic assistance improves discharge uniformity and limits localized thermal loading, thereby enhancing surface integrity and reducing Cu-Al 2 O 3 electrode wear.
Institutions: Xinjiang University, Xinjiang Institute of Engineering
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,640
OpenAlex ID: W7207843665