Machinability analysis during finish turning Ti6Al4V with varying cutting edge radius

ABSTRACT

The effect of cutting edge radius (rβ) on the chip formation mechanism during the finish turning of Ti6Al4V is studied. An increase in r_β decreases the cutting to thrust force ratio and produces lower chip thickness due to the increase in plowing zone depth. Larger radius tools produce thinner loosely curled chips whereas tightly curled thicker chips are formed for the unprepared edge tool (36 µm). As r_β increases, the chip flow angle (β) increases and free-flowing chips with reduced up-curl but increased side and lateral curl and consequently larger resultant chip curl radius are produced. The chip serration height to overall chip thickness ratio increases whereas chip core thickness reduces owing to the increased plowing action as r_β increases. Chip segmentation analysis reveals increased serration height, thermal instability, and shear localisation in the shear zone due to the increased ploughing effect beyond ~60 µm edge radius.

KEYWORDS:

• Edge
• radius
• plowing
• chip
• morphology
• curl
• radius
• segmentation
• height

Acknowledgments

The authors thank The Department of Science and Technology, Government of India for funding this work under the DST - Early Career Research award (File Number: ECR/2017/000893).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The work was supported by the Science and Engineering Research Board [ECR/2017/000893].