Inhibition of cracking by grain boundary modification in a non-weldable nickel-based superalloy processed by laser powder bed fusion

A TiC nanoparticle modified non-weldable nickel-based superalloy Inconel 738LC has been fabricated via laser powder bed fusion. The formation of refined grains with a larger high angle grain boundary length density and zigzag grain boundaries inhibits the initiation and propagation of hot cracks, leading to a 97% reduction in cracking and improved mechanical properties.