Abstract The current research comprises of various machinability aspects of 4340 hardened alloy steel which are scrutinized with in context of improvements in main cutting force, tool flank wear, crater wear, surface roughness, micro-hardness, machined surface morphology, chip morphology, chip reduction coefficient and apparent coefficient of friction under three different cutting fluid applications i.e. compressed air, water soluble coolant and nanofluid (using eco-friendly radiator coolant as the base fluid and Al2O3 as the nanoparticle) using uncoated cermet cutting inserts and a comparative assessment was performed to select which fluid performed better in terms of various machining attributes among three cutting fluids. The minimum quantity lubrication technique (MQL) was used in which a smaller volume of coolant sprinkled at high pressure. This method is found as the most effective alternative to minimize health risks and machining costs, which is quite high in other setups. The test specimen was machined at three different cutting speeds i.e. 100, 120 and 140 m/min along with two machining parameters i.e. feed and depth of cut were kept constant respectively at 0.2 mm/rev and 0.4 mm. Outcomes made a conclusion that Al2O3 enriched ecofriendly nanocoolant outperformed both compressed air and water soluble coolant in terms of every machinability aspects.

中文翻译：

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MQL 和纳米流体对硬化合金钢切削加工性能的影响

摘要 目前的研究包括 4340 硬化合金钢的各种机械加工性能方面的改进，包括主切削力、刀具后刀面磨损、月牙洼磨损、表面粗糙度、显微硬度、加工表面形态、切屑形态、切屑减少量。三种不同切削液应用下的系数和表观摩擦系数，即压缩空气、水溶性冷却剂和纳米流体（使用环保的散热器冷却剂作为基液，Al2O3 作为纳米颗粒）使用未涂层的金属陶瓷切削刀片进行比较评估在三种切削液中选择哪种切削液在各种加工属性方面表现更好。使用了最小量润滑技术 (MQL)，其中在高压下喷洒少量冷却剂。这种方法被认为是将健康风险和加工成本降至最低的最有效替代方法，这在其他设置中相当高。试样以三种不同的切削速度进行加工，即 100、120 和 140 m/min，以及两个加工参数，即进给和切削深度分别保持恒定在 0.2 mm/rev 和 0.4 mm。结果得出的结论是，富含 Al2O3 的环保纳米冷却剂在各个可加工性方面都优于压缩空气和水溶性冷却剂。2 毫米/转和 0.4 毫米。结果得出的结论是，富含 Al2O3 的环保纳米冷却剂在各个可加工性方面都优于压缩空气和水溶性冷却剂。2 毫米/转和 0.4 毫米。结果得出的结论是，富含 Al2O3 的环保纳米冷却剂在各个可加工性方面都优于压缩空气和水溶性冷却剂。