Influences of Feed Rate and Machining Length in Micro-milling of P-20 Steel

Abstract

This study is focused on the influences of feed rate and machining length upon the significant machining parameters such as cutting force, surface roughness, burr size and microhardness. For this case study, micro-milling operation has been carried out for the combination of TiAlN-coated 0.5-mm flat end mill and P-20 steel in dry environment. To avoid the ploughing effect, experiments have been performed in shearing dominated region for three feed rates, viz. 1, 2 and 3 µm/tooth up to a machining length of 350 mm, each. The experimental results revealed that with increase in feed rate and machining length, the magnitude of machining parameters increases. The magnitude of cutting force and surface roughness increases with machining length due to tool wear effect, and microhardness value increases due to strain hardening. The magnitude of burr width also increases with increase in feed rate and machining length due to more chip load and deterioration of sharpness of the tool, respectively.