Critical depth of cut and asymptotic spindle speed for chatter in micro milling with process damping

A review on micro-milling: recent advances and future trends

“…Burr may be formed on the machined features of the material if the cutting tool plastically deforms the uncut material instead of removing them, which may be caused by the following main issues: (i) the uncut (theoretical) chip is not supported by any material or special supporting fixtures [100], (ii) the cutting edge radius and ploughing effect are relatively large [46,101] (iii) the tool run-out is significant [46,101], (iv) extensive and uncontrolled vibration (chatter) complicates the process [54,82,102], or (v) the type and position of the micro-particles of the part are unfavourable [62,103]. Micro-groove-milling induced burr occurrence can be seen in Fig.…”

“…In addition to the low stiffness of the tools, the high specific cutting force-at small depth of cut values-also makes the optimization of the micro-milling process more difficult [135]. However, the stability of the micro-milling process can be improved by (i) the increased process damping due to the ploughing phenomenon, and by (ii) the increased contact area of the clearance surface and the workpiece [102,136]. Cutting tool vibration can be modelled using springs and attenuations [137][138][139].…”

“…The Al7075-T6 is widely used in the aerospace industry because its specific material properties are excellent: it has a good volume-to-weight ratio, high strength and toughness and antioxidant [36]. Copper micromachining is also a highly researched field [40,102,110,120]. Inconel 718 [41,85,[158][159][160], a nickel-based superalloy, has been reported in several publications.…”

Finite element simulation of high speed micro milling in the presence of tool run-out with experimental validations

“…The tool diameter (AB ) can be fixed at 0.782 mm (i.e., the average of the measurements). As demonstrated in reference [10], by using the law of sines on triangle AOB (Fig. 4b), β and δ are determined.…”

“…In the recent decades, a large number of publications are dedicated to understand micro milling processes. These are mainly concerned with miniature machine tool development, process modeling to achieve a greater understanding about cutting force generation and mechanistic modeling [6][7][8][9], chatter vibrations [10], workpiece defects and surface quality, tool edge effects [11], tool run-out effects [12,13], thermal stability [14], and many other issues. Last several years, researchers also dealt with the possibility of implementing predictive process models with finite element (FE) simulations [13,[15][16][17][18], a useful capability to refine the knowledge about force generation and chip formation in micro milling.…”