Chip Formation and Minimum Chip Thickness in Micro-milling

In the current context of miniaturization, micro-machining processes are in full expansion. One of them is micro-milling. Although micro-milling is based on the same principle as macro-milling, the phenomena of micro-cutting are not a simple scaling of macrocutting. A significant difference is the chip formation involving the phenomenon of minimum chip thickness. In micro-milling the depth of cut and the feed are very small, of the same order of magnitude as the tool radius and below a certain value no chip is formed. This paper reports the current state of the art of chip formation and minimum chip thickness in micro-milling from an experimental and numerical point of view. It presents the differences and difficulties of micro-milling compared to macro-milling on chip formation, as well as experimental and numerical work in this area. Finally, results of finite element simulations to quantify the minimum chip thickness and model the chip formation are presented.