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In this paper an innovative vibration rotary tool was designed and manufactured. Vibration turning tool is a compound of turning rotary tool and ultrasonic assistant turning. In this tool, an ultrasonic wave generator with power equal to 20 KHz transducer that has a rotational motion during the process was used. For tool vibration, a stainless horn with resonance frequency equal to 20618 Hz, were designed and manufactured. Round insert with 10 millimeter diameter were used. One of the most important key points in this setup is that the simultaneous rotation and vibration has to be achieved. For rotational motion a motor power and a rack and pinion were used. Also a structure with ability to mount on turning machine were designed and manufactured. Cutting force and surface roughness for each experiment were measured and compared with data collected from conventional rotary tool on 7075 aluminum material. Results shows that ultrasonic vibration cause decreasing in cutting tools and surface roughness, tremendously.

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This paper studies the effects of soluble cutting fluid-based CuO Nanofluid on machining force and surface roughness in turning of hardened AISI 4340 tool steel. These influences, Moreover, are compared with the outputs of similar tests through dry and soluble cutting fluid. The obtained results showed 1% volume fraction of CuO Nanoparticles added to soluble oil as cutting fluid was considerably reduced machining force and surface roughness in comparison to soluble cutting oil and dry. The investigations indicated that CuO Nanofluid reduced surface roughness and machining force by 49% and 24% respectively. Moreover, the results illustrated that the lowest surface roughness obtained in cutting speed 250 m/min, feed rate 0.1 mm/rev and cutting nanofluid.

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In this research, the effect of parameters of cutting speed, feed rate and machining time at constant cutting depth on tool wear and its effect on the surface roughness of hardened steel 4140 and machining forces were investigated. First, 4140 steel was prepared and its hardness was increased to 45 HRC under heat treatment, and then the TCMW 16T304 H13A tool was prepared from uncoated cemented carbide for machining. The design of the experiments was carried out in a full factorial manner. The analysis of the results was done from the analysis of variance test and the graphs related to the experimental results, based on these results, the advance rate had the greatest effect on the surface roughness and machining shear force, and the machining time had the greatest effect on the machining advance force and Cutting speed also had the greatest effect on tool wear. The highest amount of tool wear was equal to 0.89 mm and the lowest amount of tool wear was equal to 0.41 mm. The best surface quality was measured as 0.372 μm and the highest surface roughness was measured as 1.154 μm. The maximum shear force was 172.7 N and the minimum shear force was 54.2 N. The maximum forward force was equal to 156.59 N and the minimum forward force was equal to 45.86 N.

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When working with hardened materials, it's important to control and optimize the surface roughness and machining force. To achieve this, we can use intelligent methods that are based on prediction and optimization models. In this study, an artificial neural network was used to evaluate the surface roughness and machining force of hardened steel 4140 by analyzing cutting speed, feed rate, and machining time. A full factorial method was used to carry out 27 experiments, and an uncoated cemented carbide tool TCMW 16T304 H13A was used to measure surface roughness and machining force during turning. An artificial neural network model with two hidden layers was selected as the optimal architecture for separately predicting surface roughness and machining force. The predicted values were then compared with the experimental results, and the average error percentage for validation data was calculated as 4.25% for surface roughness and 5.11% for machining force. Finally, the optimal cutting parameters were selected to minimize surface roughness and machining force.