Burgeoning demand for machinability, health, and ecology, Environmental Protection Agency (EPA) regulations are pushing the modern manufacturing sector to apply dry or biodegradable cutting fluids, which are insufficient in the machining of difficult-to-cut materials. Therefore, this study is devoted to proposing a newly developed hybrid ethanol-ester oil lubri-coolant for machining titanium alloy. To encompass the effectiveness of the proposed cutting medium, the thermophysical properties (density, thermal conductivity, viscosity, specific heat), and tribological properties (friction coefficient, friction force), and investigated. Besides, the machinability performance of hybrid lubri-coolant is determined in terms of cutting temperature, cutting force, surface roughness, residual stresses, tool wear through minimum quantity lubrication (MQL) system in the high-speed machining of heat-treated Ti-6Al-4V. The machinability performance of hybrid lubri-coolant are compared to dry cuttings. Findings have depicted that density, viscosity, and thermal conductivity were decreased with the increase of temperature while specific heat was increased with the increase of temperature. Tribological characteristics showed the highest friction coefficient and friction force under dry conditions while minimum under hybrid ethanol-ester oil (1:1) conditions. The hybrid ethanol-ester oil lubri-cooling in milling showed lower cutting temperature, cutting force, surface roughness, residual stresses, and minimum tool wear results. The hybrid ethanol-ester oil is biodegradable, providing efficient cooling with the evaporation of ethanol, and lubrication due to long-chain ester oil molecules. The polar nature of ethanol and ester oil prevented microparticles adhesion and made a tribo-film on the tool-workpiece and prevented rubbing or frictional heat generation.

对可加工性、健康和生态的迅速增长的需求，环境保护署 (EPA) 的法规正在推动现代制造业应用干燥或可生物降解的切削液，这些切削液在难切削材料的加工中是不够的。因此，本研究致力于提出一种新开发的混合乙醇-酯油润滑冷却液，用于加工钛合金。包括所提出的切削介质的有效性、热物理特性（密度、热导率、粘度、比热）和摩擦学特性（摩擦系数、摩擦力），并进行了研究。此外，混合润滑冷却液的切削加工性能由切削温度、切削力、表面粗糙度、残余应力、在热处理 Ti-6Al-4V 的高速加工中通过最小量润滑 (MQL) 系统减少刀具磨损。混合润滑冷却液的机械加工性能与干切屑进行了比较。研究结果表明，密度、粘度和导热系数随着温度的升高而降低，而比热随着温度的升高而增加。摩擦学特性表明在干燥条件下摩擦系数和摩擦力最高，而在混合乙醇-酯油 (1:1) 条件下最低。铣削中混合乙醇-酯油润滑冷却显示出较低的切削温度、切削力、表面粗糙度、残余应力和最小的刀具磨损结果。混合乙醇酯油是可生物降解的，通过乙醇的蒸发提供有效的冷却，和润滑由于长链酯油分子。乙醇和酯油的极性可防止微粒粘附并在工具工件上形成摩擦膜并防止摩擦或摩擦生热。