[RETRACTED] Experimental Study on Impact of Thermal-Assisted Machining on SKD11 Steel Machinability

Abstract

Machining in a heated environment has been used in pressure machining and metal cutting. Thermal-assisted machining is a new machining method performed on conventional machine tools, CNC machines, in which the workpiece is heated before machining. Different heat sources do the thermal-assisted: electrical energy, laser beam, magnetic induction. However, there is very little research on thermal-assisted machining when milling SKD11 steel, a difficult-in-processing material but widely used in the industry. Material machinability refers to the ability of material machining that is difficult or easy. Material machinability is measured by tool life, material removal ability, shear force, cutting vibration, surface roughness. The material's machinability is directly influenced by its microscopic structure and is related to the cutting mode. This paper has highlighted the study of material machinability when thermal-assisted machining and compared to the conventional one. This study also highlights the crucial role in assessing the effect of heating on the SKD11 steel machinability. This study analyzed the technological parameters' role on the shear force, chip shrinkage, surface roughness, and shear vibrations during normal machining and SKD11 steel heating. The study results showed that the material's microstructure and the amplitude of vibration did not change under the heating process's effect with a temperature range of 200 o C -400 o C. However, the shearing force during heat processing is drastically reduced compared to conventional machining. Chip shrinkage increased by 31.7% when heated to 400 o C, while roughness decreased by 47.1%.

A Novel Approach of Heat Assisted Parallel Turning Process

“…wheather for Inconel 718, the effective cutting depth was 0.3 mm, the force exerted on tool was reduced by 8.73 to 34.3% and surface roughness was reduced by 16.3 to 45.2% at optimum heating temperature of 900°C [30]. When SKD11 steel was heated by electromagnetic induction, the microstructure and amplitude of vibration did not alter below 400 o C and chip shrinkage was increases by 31.7%, cutting force decreases by 65.1%, and surface roughness decreases by 47.1% [31].…”

The Effect of Chip Binding on the Parameters of the Case-Hardened Layer of Tooth Surfaces for AMS 6308 Steel Gears Processed by Thermochemical Treatment

“…However these technics cannot be directly applied to gear teeth surfaces improvement due to the specific geometric shape of gear teeth. While the phenomena which occur during machine cutting or abrasive machining process and their effect on the surface layer are widely discussed in the available references [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ] and the industry norms applied in the assessment of microstructure, the question of machining prior to case carburizing of the surfaces to be exposed to considerable and dynamically variable loads is less extensively detailed in research work. However, it is known, that certain external factors related to machining could result in local changes in the carburized case parameters to a point capable of negatively affecting the mechanical performance of the carburized case.…”