Simulation Analysis and Experimental Study on SLM Forming Titanium Alloy Milling Hole

Abstract

Using finite element analysis software and based on the Johnson–Cook failure criterion, a 3D printing workspace model with collapse, powder sticking, and cavity defects was established under the selective laser melting (SLM) forming process. The simulation analysis of milling holes was carried out, and the relationship between cutting speed and material-removal rate on tool wear and entrance burr was derived. The hole-milling experiment was carried out to verify the dimensional accuracy and surface appearance of the hole under the two processes of SLM direct forming and re-milling after forming; the inhibition effect of re-milling after forming on collapse, powder sticking, and cavity defects in hole forming were studied, and the formation mechanism of various defects such as burrs, scratches, and hole-wall cracks in the hole-milling process was analyzed. The Kistler9129A dynamometer was used to measure the cutting forces of re-milling holes and direct milling holes, and a comparative analysis was carried out. The influence of cutting speed, hole diameter, and material-removal rate on the axial force of milling holes was explored. The experiment results were consistent with the simulation cutting model, and the model’s accuracy was verified.