MSE Seminar: “Healing of Stripe Boundary Defects in Direct Metal Laser Melting of Ti-64” – Kevin Chaput, Ph.D.

Date(s) - 10/08/2019
3:00 pm - 4:00 pm

Rhines Hall 125


Recently, an effort using intentionally abbreviated direct laser melting (DMLM) builds for a range of process conditions was completed to couple the topography of a printed layer and scan strategy to the severity and proclivity of persistent systematic defects within Ti-6Al-4V. During this effort one of the most severe and common defects observed was a periodic array of pores that coincided with stripe boundaries in the scan strategy. Evaluation of the abbreviated builds showed that these stripe boundary defects corresponded to a depression that formed as the laser turns off and changes vector at the end of a hatch. As a continuation of previously presented work which reported the effect of process parameters on the severity of these defects, this work examines the healing mechanism of these pores through the use of 3D characterization. Novel scan strategies, identified through modeling, were also be explored to aid in the healing process.