Burr size investigation in micro milling of stainless steel 316L

Abstract

Deburring of micro-parts is one of most complicated operations used in manufacturing of micro sized components. Therefore, restriction of burr formation is one of main objectives of micro-cutting processes. To achieve the aim, basic understanding of micro-cutting mechanism and selection of optimized parameter are required. In the present work, an attempt was made to study burr size in microgroove cutting process. Here, effect of parameters such as spindle speed, feed rate and depth of cut on burr height and thickness are studied under two types of micro-milling process i.e. up-milling and down-milling. The obtained results revealed that the type of milling process significantly influenced the values of burr height; where, application of up-milling causes a mean reduction of 100% in burr height with respect to down-milling process. It is also found from the results that irrespective to type of micro-cutting process, the burr height increases by increase of spindle (up to 2000 RPM) speed and depth of cut (up to 0.3 mm). However, feed rate shows different behavior, where increase of feed rate (up to 5 mm/tooth) causes further burr height in down-milling and less bur height in up-milling. About the burr thickness, the result revealed that the irrespective to variation of process parameters, up-milling process cause about 20% increase in burr thickness. On the other hand, it is found that irrespective to type of micro-milling process, the burr thickness increases by increase of spindle speed and it decreases by increase of feed rate. Moreover, the thickness shows a falling and rising behavior as the depth of cut increases from 2 to 5 mm/tooth.