%0 Journal Article
%T Applicability of Tool Condition Monitoring Methods Used for Conventional Milling in Micromilling: A Comparative Review
%A Soumen Mandal
%J Journal of Industrial Engineering
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/837390
%X Micromilling is a contact based material removal process in which a rotating tool with nose radius in microns is fed over a stationary workpiece. In the process small amount of material gets chipped off from the workpiece. Due to continuous contact between tool and workpiece significant damage occurs to the cutting tools. Mitigating tool damage to make micromilling systems more reliable for batch production is the current research trend. In macroscale or conventional milling process a number of methods have been proposed for tool condition monitoring. Few of them have been applied for micromilling. This paper reviews different methods proposed and used in last two decades for monitoring the condition of micromilling tools. Applicability of tool condition monitoring methods used in conventional milling has been compared with the similar ones proposed for micromilling. Further, the challenges and opportunities on the applicability issues have been discussed. 1. Introduction Micromilling process has achieved significant popularity in production industries due to its exceptional capability to generate precise holes to complex 3D features. Micromilling process involves removal of material from a workpiece by a rotating tool with nose radius in microns. The material removal process results in a host of effects such as tool wear, generation of contact machining forces leading to tool deformation, chatter and vibration, and tool stress causing tool breakage [1]. These stated effects heavily depend on type of milling operation (vertical, horizontal, ball end, and face) [2], operating conditions [3] (temperature [4] and tool-workpiece alignment), parameter selection (feed, rpm, and depth of cut) [5], tool (PCD, CVD, PCBN, and metallic) [6], and workpiece materials (metals, polymers, semicrystalline, and amorphous) [7]. Due to influence of tool condition on myriad parameters, monitoring the same seems to be a real time multivariate problem. It is a well-known fact that almost all CNC milling machine manufacturers state the optimum machining conditions in their industrial datasheets. Even on maintaining these conditions strictly, tool damage is prevalent in micromilling process as no datasheet can provide all combination of optimum machining parameters. In addition, micromilling process in total requires a number of critical steps. Tool positioning at beginning of the process demands dexterity of the machine operator as a slight error may lead to tool failure before any machining has taken place [8]. Due to miniature footprint of the tool, often a tool with broken
%U http://www.hindawi.com/journals/jie/2014/837390/