On the improvement in process performance of ceramic inserts during hard turning in MQL environment

ABSTRACT

Hard turning process, frequently used to finish the rotational surfaces of hard steel components, has some major issues like a high tool wear rate coupled with the degradation of surface finish and generation of brittle white layer. Due to this, the process productivity also remains low. In an attempt to improve the cutting tool productivity while machining hardened EN31 steel, uncoated ceramic inserts were used with the Minimum Quantity Lubrication (MQL) environment, which resulted in significant wear reduction on the ceramic inserts along with a better surface finish than that produced with a dry cutting. The most suitable process parameters, to produce an efficient cut, i.e., high process performance on both wear and surface finish fronts, were proposed. The surface integrity produced within the process parameter window identified was compared for both dry and MQL environments. It was confirmed that application of MQL brought about a significant reduction in formation of subsurface white layer both at lower and higher feeds (around 40% and 16.5% respectively) when compared to dry mode cutting. MQL condition enhanced the overall productivity of ceramic inserts with lower flank wear and better surface characteristics even at higher feeds, while at the same time, producing a thinner white layer.

KEYWORDS:

• Turning
• MQL
• AISI52100
• roughness
• ceramic
• tool
• wear
• white
• layer

Acknowledgments

The experimental work is a part of a project funded under TEQIP-II scheme of World Bank on “Development of Minimum Quantity Lubrication setup for improved surface integrity during hard turning” done at HBTU Kanpur. The analysis work was done at IIT Bhubaneswar.

Additional information

Funding

This work was supported by the TEQIP II project at HBTU Kanpur.