Effects of Topography and Modified Layer by Plasma-Shot Treatment on High-Speed Steel

Abstract

In this study, plasma shot (PS) treatment was applied to high-speed steel (HSS) surfaces using a titanium carbide electrode to confirm the effect of discharge current (I p) on the formation of a single dimple and analyze a modified layer. The roughness of modified surfaces increased when I p increased, and energy-dispersive X-ray spectrometry showed an increase in titanium atom density when I p and electrode consumption volume (V e) increased. A friction test confirmed that the modified surface's friction was reduced by discharge dimples under low-load conditions. Vickers hardness test confirmed that the hardness of the modified surface was ~ 300-600 HV higher than that of an untreated HSS surface. Moreover, it increased with an increase in I p. However, application of PS treatment to the edge of surfaces on the workpiece caused shape deterioration. The deterioration size of the edge of the modified layer increased when I p increased. To solve this issue, we propose a novel method named position-adjusted PS (PA-PS) treatment. PA-PS treatment is used to adjust the end of the electrode in the order of tens of micrometers from the edge of the workpiece to avoid the deterioration of the edge form. Under I p = 21 A, PA-PS formed a modified layer without deteriorating the edge shape of the workpiece, thus confirming the PS characteristics applied to HSS surfaces. Moreover, PA-PS treatment solved the shape deterioration of the edge on modified surfaces via PS treatment.

Power Dissipation of an Inductively Coupled Plasma Torch under E Mode Dominated Regime

“…In temperature measurement terms, the temperature difference of the coolant is likely to decrease because the EM fields are theoretically better coupled with the core of the plasma. For this research, the focus is to present an alternative method for in-process monitoring of the torch efficiency, typically for the plasma surface applications, e.g., plasma torch etching [ 24 ], surface treatment [ 25 ] and coating [ 26 , 27 ].…”

A Review of Simulation Modeling of the State Evaluation and Process Prediction of Plasma Processing under Atmospheric Pressure

“…DC discharges are typically operated in two modes [8], namely, pulsed mode, which involves short-duration situations with intermittent energy input, and 2) continuous mode, which enables stable, long-time, and significant energy input. For AC discharges, characterized by alternating fields in energy sources, three primary categories exist, namely, those m −3 ) Applications Spraying [3,[26][27][28][29][30], etching [2,31,32], waste treatment [33,34], welding [35,36], surface modification [37,38] Surface modification [1,39], surface treatment [4,5,40,41], synthesis [5,42], nanomanufacturing [43][44][45][46], film deposition [47][48][49], pollution control [42,50] utilizing alternating electric (E) fields, those using alternating magnetic (H) fields, and those employing microwave electromagnetic fields. These discharges operate across a frequency range, starting from low frequency (LF) within the kHz range, progressing to RF in the MHz range, and ultimately reaching microwave frequencies in the GHz range.…”