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10CrNi3Mo alloy steel has the characteristics of high hardness and wear resistance, and is widely used in aircraft and spacecraft, shipbuilding and so on. However, its conventional processing method has high tool loss. Wire Electrical Discharge Machining (WEDM) technology is based on electrode pulse discharge to corrode materials. There is no direct contact between the tool and the workpiece, so it is suitable for processing materials with complex shapes, such as high hardness and high brittleness. The focus of this study is to investigate the effects of different electrical parameters such as pulse width, pulse gap, current, and wire feeding speed on the recast layer thickness (RCL) and surface roughness (SR) of 10CrNi3Mo alloy steel processed by wire discharge machining using orthogonal experiments. The gray correlation method was used to optimize the above two process indicators, and seeking optimal processing parameters. The optimized recast layer thickness was 8.65 μ m. The surface roughness is 1.932 μ m. Achieve expected goals. [ABSTRACT FROM AUTHOR]

Discharge channel motion characteristics are one of the focuses of electrical discharge machining (EDM) mechanism research. Based on single pulse discharge experiments, discharge channel motion laws of wire-cut EDM (WEDM) under different electrical parameters were researched. Results show that discharge channel motion speeds are highest at the beginning of the discharge, then drop sharply, and finally enter a relatively stable state, due to the current density change, pressure difference change between the inside and outside of the discharge channel, and the electrode wire shape itself. When discharge time lasts from 0.5 μs to 5 μs, the discharge channel average moving speed drops by about 60%, and when discharge time lasts about 15–25 μs, the discharge channel diameter expands to the maximum. Continuous machining experiment reveals that the variation laws of both cutting efficiency and a single discharge crater surface area with electrical parameters are consistent, that is, the motion laws of a single pulse discharge channel can microcosmically reveal cutting efficiency variation laws in WEDM macroscopically. Improving cutting efficiency only by increasing pulse energy (especially pulse width) is difficult. In high-speed WEDM (HSWEDM) process, the pulse width exceeding 75 μs is proved to have little effect on cutting efficiency improvement. [ABSTRACT FROM AUTHOR]

In this study, the problem of poor precision and low efficiency in shape-cutting hard, brittle semiconductor materials with traditional fixed abrasive diamond wire sawing (DWS) is investigated experimentally and a novel approach, which combines electric discharge and diamond abrasive grinding into a single process, is proposed. Experiments with polycrystalline silicon materials are conducted to contrast abrasive-spark hybrid machining, diamond wire sawing, and wire electricaldischarge machining (WEDM). The results show that, under the same processing conditions, the shape accuracy of abrasive-spark hybrid machining is the highest and cylindricity error is as the lowest, at 11 μm. In comparison with WEDM, the damage-layer thickness of machined surfaces is reduced by 10 μm. Among three processing methods, hybrid machining has the minimum wire bending and wider kerf. The thickness of damage layer and the surface roughness of hybrid machining are in the middle. The surface topography is composed of shallow discharge pits and grinding areas, and there are few scratches on the cut surface compared to diamond wire-cut surfaces, such that this new machining method is found to be more suitable for shape-cutting hard and brittle semiconductor materials. [ABSTRACT FROM AUTHOR]