Laser Metal Deposition Additive Manufacturing of TiC Reinforced Inconel 625 Composites: Influence of the Additive TiC Particle and Its Starting Size

Abstract

In this study, laser metal deposition (LMD) additive manufacturing was used to deposit the pure Inconel 625 alloy and the TiC/Inconel 625 composites with different starting sizes of TiC particles, respectively. The influence of the additive TiC particle and its original size on the constitutional phases, microstructural features, and mechanical properties of the LMD-processed parts was studied. The incorporation of TiC particles significantly changed the prominent texture of Ni–Cr matrix phase from (200) to (100). The bottom and side parts of each deposited track showed mostly the columnar dendrites, while the cellular dendrites were prevailing in the microstructure of the central zone of the deposited track. As the nano-TiC particles were added, more columnar dendrites were observed in the solidified molten pool. The incorporation of nano-TiC particles induced the formation of the significantly refined columnar dendrites with the secondary dendrite arms developed considerably well. With the micro-TiC particles added, the columnar dendrites were relatively coarsened and highly degenerated, with the secondary dendrite growth being entirely suppressed. The cellular dendrites were obviously refined by the additive TiC particles. When the nano-TiC particles were added to reinforce the Inconel 625, the significantly improved microhardness, tensile property, and wear property were obtained without sacrificing the ductility of the composites.

Metal Additive Manufacturing by Powder Blown Beam Deposition Process

“…But it was observed columnar grains at low laser power [20]. The columnar dendrites were form due to the addition of TiC into the IN625, when processed by LMD [42]. The LENS processed SS316L and H13 melt pool size varies from 0.5mm-1.5mm [47].…”

A comparison framework to support the selection of the best additive manufacturing process for specific aerospace applications

“…These processes build the component by melting the raw material while it is being deposited in form of blown-powder (LMD) or wire (WAAM) (Uriondo et al 2015). In this case, both processes are assisted by shielding gas (normally argon) to minimise the oxygen presence when melting the feedstock (Gu et al 2017;Bhavar et al 2014). While WAAM uses an electric or plasma arc to melt the wire and deposit it at a controlled rate onto the previous layer (Zhang et al 2016;Wang et al 2013); LMD uses an integrated powder feeder system which directly deposits the blown powder, employing a high power laser of up to 3 kW (Graf et al 2012;Gu et al 2017).…”

A comparison framework to support the selection of the best additive manufacturing process for specific aerospace applications

“…These processes build the component by melting the raw material while it is being deposited in form of blown-powder (LMD) or wire (WAAM) (Uriondo et al 2015). In this case, both processes are assisted by shielding gas (normally argon) to minimise the oxygen presence when melting the feedstock (Gu et al 2017;Bhavar et al 2014).…”

“…Figure 3: Schematic of DED processes -LMD (Geyer 2016) While WAAM uses an electric or plasma arc to melt the wire and deposit it at a controlled rate onto the previous layer (Zhang et al 2016;Wang et al 2013); LMD uses an integrated powder feeder system which directly deposits the blown powder, employing a high power laser of up to 3 kW (Graf et al 2012;Gu et al 2017). Table 1 shows a comparison between powder-feed and wire-feed AM technology.…”