Hard turning of bearing steel AISI 52100 with carbide tool and high pressure coolant supply

Abstract

The improvement of productivity, efficiency, and product quality requires the use of modern machining equipment, and modern process management. Successful management of the cutting processes requires a lot of knowledge about workpiece materials, cutting tool materials and geometry, tool machine, cooling and lubrication fluids including dosage techniques, and cutting conditions. However, the mentioned requirements are difficult to achieve in hard turning (Fig. 1). Hard turning is the cutting process for workpiece materials which are hardened above 45 HRc. This method has been introduced to replace traditional processes, which included turning, heat treatment and grinding [1]. Hard turning is almost performed using harder cutting tool materials such are the ceramics (Al 2 O 3) and cubic boron nitride tools (CBN), at lower cutting parameter values. The use of these tools and parameters causes expensive production, because of expensive tools and long machining time. The use of brittle tools requires continuous cut due to poor toughness of cutting tool edges. Use of cooling and lubrication fluid supplied under high pressure can bring some improvements in machining. This technique of fluid supplying dates from the fifties of the last century. In modern machining are used the high pressure tool systems that allow the fluid supply under pressures up to 15 MPa. The high pressure jet assisted machining (HPJAM) concept is to inject an extremely high pressure jet of cooling and lubrication fluid in the cutting zone, between chip and tool edge. In this techniques are used pressures from 40 to 200 MPa, so that jet is participating in the chips forming, similar to the non-conventional technologies [2-4]. HPJAM was established as a method that would substantially increase the removal rate and Abstract The machining of hard-to-machine bearing steel AISI 52100 (100Cr6), hardened to 62 HRc, is almost impossible using standard machining conditions and carbide cutting tools. The purpose of this research is machinability analysis and conclusions about the conditions that allow the machining of mentioned steel with carbide tools. In this paper, the turning process is carried out using coated carbide inserts and high pressure jet assisted machining, as a special technique of cooling and lubrication. In this technique, coolant circulation system with filters, environmentally acceptable, is used. A jet of cooling and lubrication fluid under extremely high pressure (50 MPa) is directed into the zone between the cutting tool edge and the workpiece. Experimental measurements were performed for different cutting parameters. Cutting forces, tool wear, surface roughness, chip shapes, and material removal rates were analyzed. The presented results show an increase in productivity, low intensity tool wear, and surface roughness in acceptable limits.

Prediction models for on-line cutting tool and machined surface condition monitoring during hard turning considering vibration signal

“…The experimental cutting conditions and levels were shown in Table 2 and in total 18 runs were conducted. Cutting parameters are selected based on the recommendations of the tool manufacturer and through previous literatures [8,14,18,33,36]. The experimental outcomes of flank wear (VBc), surface roughness (Ra) and acceleration amplitude of vibration signal (Vy) in radial direction was presented in Table 3.…”

Effects of multi-pass turning on surface properties of AISI 52100 bearing steel

“…Singh [21] noted that compared with dry turning, the surface roughness is improved by 8%~15% in the condition of using solid lubricant. In terms of material removal rate and tool life, AISI 52100 bearing steel hard turning with high-pressure coolant supply has more advantages [22].…”

Profile Evolution and Cross-Process Collaboration Strategy of Bearing Raceway by Centerless Grinding and Electrochemical Mechanical Machining

“…High-precision rotary parts are indispensable in modern industry [ 1 , 2 ]. For example, high-precision bearings are widely used in aviation, railroads, automobiles and other industries.…”