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This paper analyses three components of total cutting force and chip shape changes when finish turning 17-4 PH (precipitation hardening) stainless steel. A Finite Element Method (FEM) simulation of cutting forces was also performed using the Johnson&ndash, Cook constitutive model. The results were compared with those obtained from experimental studies. Variable feeds of 0.05&ndash, 0.4 mm/rev and depth of cut of 0.2&ndash, 1.2 mm with a cutting speed of 220 m/min were used. The studies were carried out under dry and wet cooling conditions and with the use of minimum quantity lubrication (MQL). This research was realized based on the Parameter Space Investigation (PSI) method. Statistical analysis of the obtained results was carried out using Statistica-13 software. It was found that the cutting force Fc and feed force Ff depend on the depth of cut and feed, and the passive force Fp depends mainly on the feed. Compared to dry cutting conditions, a reduction of 43% and 39% of the cutting force Fc was achieved for wet machining and MQL machining, respectively. Regardless of the cooling conditions, a favorable chip shape was registered for ap = 1&ndash, 1.1 mm and f = 0.25&ndash, 0.3 mm/rev. Compared to the experimental studies, the FEM simulation showed differences of ~13% for the cutting force Fc and of ~36% for the feed force Ff.

The work presents methods of cooling during turning of AISI-1045 steel: dry machining, minimum quantity cooling (MQC) and minimum quantity cooling with EP/AW (MQC + EP/AW) additives. Due to the increased number of variables (change of the parameters of cutting and forming emulsion mist), the method of Parameter Space Investigation was employed. The measurement of the cutting force was performed by means of a Kistler dynamometer type 9129AA and power consumption was measured with the use of a network parameter measurement device, MPS7. It has been found in the investigation that the air flow intensity has a crucial impact on the formation of the active medium in the MQC method. The lowest values of the cutting force and power have been observed when using the MQC + EP/AW method. Addition of phosphorate ester to the emulsion mist has resulted in an improvement of lubricating properties of the active medium by direct influence of the chemically active compounds in the cutting zone and, consequently, significant reduction of the cutting force and power in the process of turning the AISI-1045 steel.

316L stainless steel has emerged as one of the most used material in design and manufacturing for automotive, aerospace, marine, civil nuclear to produce critical components (valves, seats, pipes etc.). Despite, their huge application, during the machining of 316L stainless steel numerous challenges arise in terms of tool wear that are very detrimental for the surface of machined part. To obtain an extended life of tool used for machining commonly 316L stainless steel two different methods of cooling based on minimum lubrication condition, namely Minimum Quantity Lubrication (MQL) method and Minimum Quantity Cooling Lubrication (MQCL) with the addition of extreme pressure and anti-wear (EP/AW) method, respectively were settled. The use of the MQL method resulted in a reduction of the cutting tool wear by approximately 9% compared to the MQCL + EP/AW method and by approximately 21% compared to dry machining. Further, the highest values of wear indices were achieved during dry machining and the lowest ones in the method of minimized lubrication which validate the minimum lubrication as beneficial for reducing the wear progress.