Abstract
Selective laser melting (SLM) is an additive manufacturing (AM) process that is used to create complex geometries that are either impossible or cost prohibitive with conventional methods. This type of AM process is time consuming because a part must be printed a single layer at a time where each slice of the part is melted by a laser. New programmable laser technology is currently being implemented into SLM machines to reduce processing times. Beam energy density profiles can be changed in process depending on the need. Wider beam profiles can be used for rapidly melting internal fill areas, while small profiles are used for fine detail or external features. Process parameters such as laser power, scan speed and hatch distance are necessary to develop and optimize for each material and laser mode that a manufacturer will use. Using optimal process parameters ensures that the SLM process will produce a mechanically stable and repeatable part while reducing the processing time. In this thesis, process parameters for Ti-6Al-4V were developed for a DMG Mori LT 30 SLM US machine equipped with a nLight programmable laser. Mode 5 parameters were developed, and tensile tests were performed to compare strength and productivity to Mode 6. Tensile strength and modulus of elasticity for both laser profiles were within 1% of each other while Mode 5 achieved an approximately 7% increase in productivity over Mode 6.