Experimental Study on Hybrid Ultrasonic and Plasma Aided Turning of Hardened Steel AISI 4140

Abstract

Several methods such as plasma enhanced turning (PET) and ultrasonic-aided turning (UAT) have been introduced to assist conventional turning (CT) in order to overcome the difficulties of hard turning. There exist extensive experimental researches which have shown the feasibility of PET and UAT in hard turning. This paper investigates the cutting force and surface roughness in hybrid plasma and UAT hybird turning (HYT) on the AISI 4140 hardened steel. The studied parameters are turning parameters (cutting speed, feeding rate, and depth of cut), tool material, plasma, and ultrasonic parameters. For this purpose, a model was developed to relate current of plasma to the material removal temperature. The plasma and ultrasonic equipment were installed on the lathe, then hybrid ultrasonic and plasma aided machining was applied on AISI 4140 hardened steel for experiment using Taguchi design. Results showed the reduction of cutting forces in hybrid machining in comparison with CT, PET, and UAT; and depending on cutting conditions, workpiece surface roughness can be improved in hybrid machining in comparison with CT, PET, and UAT.

Effect of cutting edge modification on the tool flank wear in ultrasonically assisted turning of hardened steel

“…Cutting process instability with large unexpected vibrations is the most commonly observed problem in low speed turning of hard materials which apply intensive fluctuating forces on the cutting tool, causes tool chipping, high tool wear rate and premature tool failure. 31,33…”

“…Significant reduction of cutting forces can be seen in Figure 4 as were indicated in previous researches. 24,33,34 For instance, Figure 4(a) shows a 40% reduction in the UAT cutting force compared to the CT at 34 m/min cutting speed. As shown in Figure 4(b), it is clear that the most reduction in cutting force in UAT happens in low cutting speeds.…”

“…In the UAT with 1D vibrations, if the vibrations are applied in direction perpendicular to the workpiece axis ( Figure 2(a)), the tool tip encounters with the machined surface when the tool comes back at each vibrational motion and prevents separation of tool flank surface from workpiece. 33 If the vibration direction is exactly tangent to the real cutting direction, V C,real (Figure 2(b)), the tool flank is constantly in contact with the workpiece. The direction of real cutting speed u v can be derived from following relations…”

Experimental study on the wettability of microtextured surfaces generated by the ultrasonic-assisted face turning

“…Also, it can significantly improve the processing efficiency, surface quality, and reduce cutting forces without limitation on machining material removal rate. [23][24][25][26][27] The UAT is proposed in this paper to investigate the morphologies of machined surfaces in the face turning. The ultrasonic vibration texturing process, by adding an extra motion component to the cutting tool tip, generates microdimple (periodic ripples).…”

Experimental Study on Hybrid Cryogenic and Plasma-Enhanced Turning of 17-4PH Stainless Steel

“…In this technique, an external heat source is used to decrease hardness of workpiece material [18][19][20]. To achieve this goal, Leshock et al [21] used plasma enhanced machining (PEM) and applied plasma as heat source.…”