Novel Uses of Al₂O₃/Mos₂ Hybrid Nanofluid in MQCL Hard Milling of Hardox 500 Steel

Abstract

In recent years, the application of environmentally friendly cutting fluids in the metal cutting industry has been a growing concern in all over the world. In this study, the minimum quantity cooling lubrication (MQCL) technique, which uses very small amount of cutting oil, is motivated to apply to the hard milling process of Hardox 500 steel. Further, rice bran oil, a natural biodegradable oil, is used as the base fluid of Al2O3/MoS2 hybrid nanofluid. ANOVA analysis is used to study the influences of nanoparticle concentration, cutting speed, and feed rate on surface roughness. The obtained results indicate that good surface quality is achieved and the cutting speed is significantly increased to 140 m/min (about 2.55–2.80 times higher than the recommended values) due to the better cooling and lubricating effects from MQCL system and Al2O3/MoS2 hybrid nanofluid. Moreover, the microstructure of the machined surface proves the formation of MoS2 tribo film by using Al2O3/MoS2 hybrid nanofluid, indicating that the effectiveness of each type of nanoparticle in hybrid nanofluid has been promoted. Furthermore, the important technical guides for machining Hardox 500 steel are provided.

Keywords

• hard milling
• MQCL
• nanopartilces
• nanofluid
• Al₂O₃/MoS₂ hybrid nanofluid
• difficult-to-cut material