Product Code: ICA12_302

Residual Stress Control in DMD Process
Authors:
Hyung Min Chae, NSF Center for Lasers and Plasmas in Advanced Manufacturing, Department of Mechanical Engineering, The Univ. of Michigan; Ann Arbor MI USA
Jyoti Mazumder, NSF Center for Lasers and Plasmas in Advanced Manufacturing, Department of Mechanical Engineering, Department of Materials Science and Engineering, The Univ. of Michigan; Ann Arbor MI
Presented at ICALEO 2012

The material fabricated by the Laser aided Direct Metal Deposition (DMD) process experiences extreme cyclic thermal loads during the process, which builds relatively high residual stress. The residual stress is directly related to fracture and fatigue behavior of the product; therefore, controlling residual stress in DMD process is essential. However, online monitoring of mechanical deformation is difficult and requires high costs. In this study, the numerical models developed in the Center for Laser Aided Intelligent Manufacturing (CLAIM) at University of Michigan have been used to find the techniques to control mechanical deformation in the stage of generating tool paths using CAD program. The numerical studies include the investigation of effects of scanning direction, the number of scanning for a given height of the layer, and the heat treatment by the second laser heat source on residual stress in DMD process.