A comparative analysis of trochoidal toolpath with traditional toolpaths used in wire arc-based directed energy deposition process

The properties of the Wire Arc-based Directed Energy Deposition (WADED) fabricated parts are mostly influenced by the toolpath trajectory followed by the deposition head. Improper toolpath often leads to anisotropy and an increase in built time. Therefore, in this work, a novel trochoidal (TR) trajectory-based toolpath has been implemented for deposition using the WADED process. The effect of the toolpath on the deposited component is thoroughly investigated and is compared with three traditional toolpaths i.e., zigzag, weaving and spiral strategy. The layer thickness of the TR toolpath is found to be a maximum of 2.18 times higher than that of the traditional toolpath. This helps in reducing the built time and required number of layers for fabricating large mechanical components. The surface roughness of the weaving (transverse zigzag) toolpath and TR toolpath are observed to be comparable. The reheating nature of the TR toolpath promotes the formation of fine equiaxed grains throughout the deposited component resulting significant reduction in the anisotropy in mechanical properties along the deposition and the build directions. The proposed TR toolpath can minimize the built time by 82.44%, 62.41% and 42.04% in contrast to spiral, transverse zigzag and longitudinal zigzag toolpaths, respectively. Moreover, wear analysis reveals a reduction of 78.5% and 55.4% in the specific wear rate of the samples deposited through the TR toolpath as compared to the traditional zigzag toolpath. Therefore, the former toolpath has the potential in enhancing the efficiency and the effectiveness of WADED process with improved mechanical properties.