Effects of milling methods and cooling strategies on tool wear, chip morphology and surface roughness in high speed end-milling of Inconel-718
by Anthony Chukwujekwu Okafor; Paras Mohan Jasra
International Journal of Machining and Machinability of Materials (IJMMM), Vol. 21, No. 1/2, 2019

Abstract: This paper presents the results of experimental investigation of the effects of milling methods (up-milling and down-milling) and cooling strategies [emulsion cooling, minimum quantity lubrication (MQL), cryogenic cooling using liquid nitrogen (LN₂) and combined (MQL + LN₂)] on flank wear, chip morphology and surface roughness in peripheral high speed end-milling of Inconel-718. The experimental results show that down-milling generated lower maximum flank wear than up-milling for all cooling strategies, thus improves machinability. MQL cooling with down-milling generated lowest maximum flank wear of 0.072 mm after eight passes and is recommended for machining Inconel-718, whereas LN₂ cooling with up-milling generated highest flank wear of 1.984 mm after first pass only. Tool wear mechanism in up-milling is adhesion and failure modes are chipping and plastic deformation, causing rapid tool wear, while abrasion is the tool wear mechanism under down-milling causing progressive tool wear. Also, emulsion up-milling generated lowest surface roughness of 0.29 μm, whereas emulsion, MQL and combined (MQL + LN₂) cooling strategies with down-milling generated equal and second lowest surface roughness of 0.34 μm. Results show that using MQL cooling under down-milling for machining Inconel-718 can lead to significant cost saving and sustainable machining.

Online publication date: Fri, 01-Mar-2019

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

 
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Machining and Machinability of Materials (IJMMM):
Login with your Inderscience username and password:

Username:        Password:          Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email subs@inderscience.com