AISI 52100 hardened bearing steel is popular in many industrial applications due to its excellent wear resistance and high strength. Therefore, a high level of surface integrity of the same is the utmost important requirement to enhance fatigue life. Machining of hardened AISI 52100 steel is difficult because severe plastic deformation and generation of high temperature alter the surface metallurgy of the machined component and hamper the tool life. The present investigation includes a comparative analysis of surface integrity of AISI 52100 bearing steel during hard turning under different near-dry environments, namely, dry, Minimum Quantity Cooling and Lubrication (MQCL), Compressed Chilled Air by Vortex Tube (CCAVT), and Hybrid Nanofluid Minimum Quantity Cooling and Lubrication (Hybrid NF-MQCL). Soyabean (a vegetable) oil is used as cutting fluid in MQCL and base fluid in Hybrid NF-MQCL environments. To prepare hybrid nanofluid, two different nanoparticles Al₂O₃ and MWCNT, are used. The chilled air is generated through a vortex tube. The surface integrity of AISI 52100 steel was studied in terms of microhardness, the thickness of the white layer, surface roughness (R_a), and residual stresses. Higher cutting speed and feed show positive and negative correlation on surface integrity of AISI 52100 steel, respectively. Hybrid nanofluid MQCL exhibits the lowest surface roughness (0.34 μm), microhardness (625 Hv_0.1), compressive residual stresses (−168 MPa), and thin white layer (0.9 μm) in contrast, and dry machining shows higher surface roughness, microhardness, tensile residual stress, and thick white layer. In comparison, MQCL and CCAVT are found to be intermediate. It is found that hybrid nanofluid MQCL enhances the overall performance of the machined surface as compared to other near-dry techniques.

中文翻译：

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AISI 52100钢在不同干燥条件下硬车削时的表面完整性

AISI 52100淬硬轴承钢因其出色的耐磨性和高强度而在许多工业应用中广受欢迎。因此，高表面完整性是延长疲劳寿命的最重要要求。硬化的AISI 52100钢的加工非常困难，因为严重的塑性变形和高温的产生会改变被加工零件的表面冶金并妨碍工具的使用寿命。本研究包括对AISI 52100轴承钢在不同干燥环境下进行硬车削时的表面完整性的比较分析，这些干燥环境包括干燥，最小量冷却和润滑（MQCL），涡流管压缩冷空气（CCAVT）和混合动力纳米流体最小量冷却和润滑（混合NF-MQCL）。大豆油（一种植物油）在MQCL中用作切削液，在Hybrid NF-MQCL环境中用作基础油。为了制备混合纳米流体，两种不同的纳米颗粒Al_使用2 O ₃和MWCNT。冷空气通过涡流管产生。研究了AISI 52100钢的表面完整性，包括显微硬度，白层厚度，表面粗糙度（R _a）和残余应力。较高的切削速度和进给量分别对AISI 52100钢的表面完整性显示正相关和负相关性。混合纳米流体MQCL显示最低表面粗糙度（0.34  μ M），显微硬度（HV 625 _0.1），压缩残余应力（兆帕-168），以及薄白色层（0.9  μm）相反，干式加工显示出较高的表面粗糙度，显微硬度，拉伸残余应力和较厚的白色层。相比之下，发现MQCL和CCAVT是中间的。发现与其他近干技术相比，混合纳米流体MQCL增强了加工表面的整体性能。