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Nowadays, one of the most important problems in industry is the production of industrial parts from superalloys and metals with high hardness using traditional and modern machining methods, due to the waste of raw materials, wear of machining tools, and the inability to produce complex geometries.  Selective Laser Melting is one of the sub-branch of additive manufacturing technology that provides the fabrication of complex geometries from widely-used metallic materials due to the layer-by-layer production of parts. Hastelloy X superalloy is among the important superalloys in the aerospace industry and gas turbines. This research aims to fabricate Hastelloy X parts by selective laser melting with minimal defects and high relative density. For this purpose, three samples were printed in the range of volumetric energy density of laser from 50 to 90 J/mm3. The structure and porosity of different specimens were evaluated by image analysis method. It was found that the sample fabricated with the volumetric energy density of 90 J/mm3 has the least defects, the highest hardness, and a relative density above 99 percent.
 

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In this article, the effect of optimal selection of vibration and cutting parameters on cutting forces in the machining process with ultrasonic vibration assistance has been investigated and the results have been compared in two modes of conventional machining and of ultrasonic vibration assisted machining. In the investigation of the effect of ultrasonic vibration assistance on the machining process, analyzes have been carried out in different cutting speeds, and the effect of changing the cutting speed in relation to the tool's oscillation speed has been investigated. Finite element modeling and simulation has been done with DEFORM finite element software. The results show that the application of ultrasonic vibration in the machining process leads to the reduction of tangential and axial cutting and the reduction of heat resulting from the cutting process. By examining the results, it was found that in the machining process with ultrasonic vibration assistance, when the cutting speed is at least 30% lower than the vibration speed of the tool tip, the process has a favorable efficiency, and the favorable effects of applying ultrasonic vibration on the process include reducing shear forces, reducing the heat generated From cutting, reducing the friction coefficient between the tool and the workpiece, helping to improve the chip flow, etc.