Repair and Remanufacturing by Laser-based Additive Manufacturing

Laser direct deposition provides an attractive and cost effective means for repairing or remanufacturing high value engineering components.  This study demonstrates the successful repair of several industrial parts.   The first one is the repair of defective voids in turbine airfoils made of Inconel 690 based on a new semi-automated geometric reconstruction algorithm and a laser direct deposition process.  A Boolean difference between the original defective model and the final reconstructed model yields a parameterized geometric representation of the repair volume. The second is remanufacturing of an industrial part made of H13 tool steel using laser deposition to determine the optimal operating parameters.   The experimental results demonstrate the effectiveness of laser direct deposition in remanufacturing and its potential to adapt to a wide range of part defects.  A Life Cycle Assessment (LCA) on the energy and environmental impacts by remanufacturing is also presented.   It was found that the ultimate tensile strength of laser deposited H13 steel is 15% to 30% higher than published values for commercial H13. A finite element model is developed to predict solid phase transformation, material hardness, and residual stresses produced by the laser deposition process based on the predicted temperature and geometry from a free-surface tracking laser deposition model. Predicted results provide a reasonable agreement with measured values.