Physical Behaviors of Materials in Selective Laser Melting Process

The quality and strength of a product fabricated by selective laser melting (SLM) process depend upon the physical behaviors of materials occur at the time of fabrication.Hence, it is necessary for the researchers to know the physical behaviours and the processing parameters which influence those behaviors to fabricate a highquality product.Numerous thermal and physical behaviours occur in the SLM process where thermal behaviors affect the physical behaviours of materials during fabrication.The notable physical behaviours are melting of powder, molten pool formation, solidification, amalgamation, separation, vaporization, spattering of powder and liquid material, Marangoni effect, capillary effect, vortex, gaseous bubble entrapment, keyhole formation, metallic vapor entrapment, explosion of the molten pool, instability of the pool, presence of powder particles without melting, partially melting powder particles, re-melting, excess heating, reheating and cooling, microstructural phase transformation, bending and shrinking.The physical behaviors are highly influenced by the manufacturing parameters namely energy density, laser power, scanning speed, hatch spacing, layer thickness, and scanning strategy.The behaviours can be regulated by controlling the mentioned processing parameters.This chapter has emphasized the physical behaviours of materials as well as the processing parameters which influence those behaviours and their effects on the product quality.