Material and technological investigation of machined surfaces of the OCHN3MFA steel

Abstract

This paper deals with the effect of selected cutting parameter values in machining of OCHN3MFA steel on AFM and SEM microstructural analysis, cutting forces, nanohardness, 2D and 3D surface roughness, and material removal rate of surface layers after machining. OCHN3MFA steel was selected and used to perform experiments. Firstly, the selected steel was investigated before machining tests, due to the checking of the initial microstructure and chemical composition. The microstructure was performed on the Tescan Vega TS 5135 scanning electron microscope (SEM) with the X-ray microanalyzer Noran Six/300, and the Oxford Instruments MFP-3D Infinity atomic force microscope (AFM). Chemical composition was analyzed on Tasman Q4 surface analyzer. All machining tests of the used samples were performed under the selected cutting parameters in the SU 50A lathe machine tool with the CNMG 120408-M5 cementite carbide cutting insert clamped in the suitable DCLNR 2525M12-M cutting tool holder. During the machining process of testing samples, individual components of cutting forces were measured on a Kistler 9257B piezoelectric dynamometer with their subsequent evaluation using software Dynoware. Other experiments following the machining process were performed, evaluating the effect of selected cutting parameters on surface hardening. Surface hardening after machining of testing samples was subsequently measured on Hysitron TI950 Triboindenter with a Cube Corner measuring tip and evaluated by software Triboscan. 2D and 3D surface roughness and material removal rate (MRR) were finally performed on Talysurf CCI Lite and evaluated by software TalyMap Platinum.

Structure Evolution of 33NiCrMoV15 Steel in Relation to Tempering Temperature

“…For all performed indentation standard trapezoid load curve with the maximum test load F = 2000 µN and t = 2 s holding period is used. These parameters have been proven in previous research focused on high strength 33NiCrMoV15 steel [11].…”

Experimental determination of continuous cooling transformation diagram for high strength steel X153CrMoV12

“…The results are presented in the form of CCT diagram, which can be useful in designing of the temperature cycles for the production and processing of high performance tool steel X155CrV-Mo12. The higher percentage of chromium in the mate- rial results in the formation of Cr 7 C 3 carbide, which results in an increased value of the hardness of the material [9,10]. Provided the martensitic transformation is achieved, the resulting critical cooling rate is set at 5 °C/s.…”

The Effect of Annealing Temperatures on Selected Properties of WC/C Coatings, Deposited Using Hexacarbonyl Wolfram in an N2-SiH4 Atmosphere

“…Tungsten carbide (WC) is often used as a thin coating, characterized by high values of hardness (42 GPa [1][2][3]), wear resistance, as well as a low coefficient of friction (COF, 0.22 [1,2]), whereas the surface hardness of unmodified steel is 5 GPa [4]. Therefore, WC is often applied for the protection of functional surfaces of machining components made of steel, and for coating high-speed steel.…”