Document Type: Research Paper


Department of Manufacturing Engineering, Faculty of Mechanical Engineering, Thai Nguyen University of Technology, Thai Nguyen, Vietnam


SKD 11 tool steel is among the most popular metals in mold industries for making different kinds of cold work molds and dies with high accuracy and long service life. The demand for higher quality, lower manufacturing costs, particularly the environmentally friendly characteristics, have provided the stimuli for manufacturers and researchers to find alternative solutions. An excellent media is formed in the cutting zone by using MQL nanofluids in order to enhance the thermal conductivity and tribological characteristics; therefore, improving the machining performance. The formation of the lubricating film as well as the rolling action of nanoparticles in contact zones has gained much attention in the machining field. In this research work, the application of MQL Al2O3 nanofluids with vegetable oils and emulsion 5% is developed for slotting end milling of SKD 11 steel using normal HSS tool. The cutting forces, tool wear, tool life, and surface roughness are investigated to evaluate the effectiveness of MQL nanofluid on cutting performance. The experimental results reveal that the cutting forces and cutting temperature decrease and the surface quality and tool life enhance. Furthermore, the improvement of the thermal conductivity of nanofluids is proven when compared to pure fluids. Due to the rise of viscosity and thermal conductivity, the soybean oil-based nanofluid, which is almost inherently nontoxic, gives superior lubricating and cooling properties suitable for MQL application compared to emulsion-based nanofluids. The novel environmental friendly technology definitely brings out many technological and economic benefits in machining practice. 

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