Abstract
This paper reports a systematic investigation on the Laser Directed Energy Deposition (LDED) based additive
manufacturing of bulk Cu structures; and microstructural and mechanical characterisation of these structures.
Full factorial experiments are carried out by varying LDED process parameters for track deposition, and process
window is identified in terms of Laser Energy per unit Powder Feed (LEPF). Further, the bulk deposition is
carried out using three inter-layer processing schemes, like - constant LEPF, decreasing LEPF, and increasing
LEPF in successive layers during deposition. Cu block deposited using increasing LEPF scheme yields relative
density around 99.9% and X-ray diffraction reveals pure Cu phase with fine crystallites. Microstructural analysis
shows the dominance of equiaxed grains, with an average size of 24.47 μm. Further, an average microhardness of
77 HV0.98 N, yield strength of 135 – 152 MPa and ultimate tensile strength (UTS) of 277 – 288 MPa are obtained
for the deposited bulk Cu structures. The obtained UTS value is higher than the strength values available in the
literature for wrought, laser powder bed fusion and LDED built Cu samples. The present study paves a methodology towards the successful deployment of the LDED process for the potential fabrication of Cu components
and parts.
manufacturing of bulk Cu structures; and microstructural and mechanical characterisation of these structures.
Full factorial experiments are carried out by varying LDED process parameters for track deposition, and process
window is identified in terms of Laser Energy per unit Powder Feed (LEPF). Further, the bulk deposition is
carried out using three inter-layer processing schemes, like - constant LEPF, decreasing LEPF, and increasing
LEPF in successive layers during deposition. Cu block deposited using increasing LEPF scheme yields relative
density around 99.9% and X-ray diffraction reveals pure Cu phase with fine crystallites. Microstructural analysis
shows the dominance of equiaxed grains, with an average size of 24.47 μm. Further, an average microhardness of
77 HV0.98 N, yield strength of 135 – 152 MPa and ultimate tensile strength (UTS) of 277 – 288 MPa are obtained
for the deposited bulk Cu structures. The obtained UTS value is higher than the strength values available in the
literature for wrought, laser powder bed fusion and LDED built Cu samples. The present study paves a methodology towards the successful deployment of the LDED process for the potential fabrication of Cu components
and parts.
| Original language | English |
|---|---|
| Pages (from-to) | 984-997 |
| Journal | Journal of Manufacturing Processes |
| Volume | 58 |
| DOIs | |
| Publication status | Published - 15 Sept 2020 |