Sub-Microstructure of Surface and Subsurface Layers after Electrical Discharge Machining Structural Materials in Water

Metals

Pavel A. Podrabinnik¹  Sergey N. Grigoriev¹  Marina A. Volosova¹  Khaled Hamdy¹  Sergey V. Fedorov¹  Anna A. Okunkova¹ 

[1] Department of High-Efficiency Processing Technologies, Moscow State University of Technology “STANKIN”, Vadkovsky per. 1, 127055 Moscow, Russia;

关键词: aluminum alloy;    electrical erosion;    erosion wear;    eutectics;    interelectrode gap;    Levenberg–Marquardt algorithm;   

DOI  :  10.3390/met11071040

来源: DOAJ

【 摘 要 】

The material removal mechanism, submicrostructure of surface and subsurface layers, nanotransformations occurred in surface and subsurface layers during electrical discharge machining two structural materials such as anti-corrosion X10CrNiTi18-10 (12kH18N10T) steel of austenite class and 2024 (D16) duralumin in a deionized water medium were researched. The machining was conducted using a brass tool of 0.25 mm in diameter. The measured discharge gap is 45–60 µm for X10CrNiTi18-10 (12kH18N10T) steel and 105–120 µm for 2024 (D16) duralumin. Surface roughness parameters are arithmetic mean deviation (R_a) of 4.61 µm, 10-point height (R_z) of 28.73 µm, maximum peak-to-valley height (R_tm) of 29.50 µm, mean spacing between peaks (S_m) of 18.0 µm for steel; R_a of 5.41 µm, R_z of 35.29 µm, R_tm of 43.17 µm, S_m of 30.0 µm for duralumin. The recast layer with adsorbed components of the wire tool electrode and carbides was observed up to the depth of 4–6 µm for steel and 2.5–4 µm for duralumin. The Levenberg–Marquardt algorithm was used to mathematically interpolate the dependence of the interelectrode gap on the electrical resistance of the material. The observed microstructures provide grounding on the nature of electrical wear and nanomodification of the obtained surfaces.

【 授权许可】

Unknown