Effect of Laser Power on Mechanical Properties and Microstructure of 316L Stainless Steel Deposited by Direct Energy Deposition(DED)

Abstract

Laser power is the most directly relevant process parameter affecting the quality in Direct Energy Deposition (DED) process In this study we investigated laser power effect on mechanical properties and microstructure of multi-layer products after vertical deposition of 40 layers using 316L stainless steel powder The mechanical properties were analyzed by three-point bending test combined with digital image correlation (DIC) to obtain strain distribution The microstructure under tensile compressive stress and neutral regions were analyzed by EBSD Considering laser power from 800 W to 2000 W 800 W has the highest yield stress of 476 MPa and 1600 W the lowest yield stress of 407 MPa due to coarsening effect By analyzing strain distribution and Schmid factor 2000 W shows low strain value and low value of Schmid factor resulting in increasing yield stress of 454 MPa

Date of Award	2019
Original language	English
Supervisor	Jui-Chao Kuo (Supervisor)