An Assessment, Definition, and Determination of the Minimum Uncut Chip Thickness of Microcutting and Impact on Machining New Powder Metallurgy Nickel-Based Superalloys

Abstract

The uncut chip thickness is comparable to the cutting edge radius in micromachining. If the uncut chip thickness is less than a critical value, there will be no chip formation. This critical value is termed as the minimum uncut chip thickness (MUCT). Although minimum uncut chip thickness has been well defined in orthogonal cutting, it is often poorly understood in practical complex turning and milling processes. This paper presents an analysis of the state-of-art research on minimum uncut chip thickness in precision micro-machining. The numerical and experimental methods to determine MUCT values and their effects on process mechanics and surface integrity in microcutting will be critically assessed in this paper. A set of definitions of minimum uncut chip thickness for three-dimensional turning and milling processes are presented. In addition, a detailed discussion on the characteristics of different methods to determine minimum uncut chip thickness and several unsolved problems are proposed for the future work.