Bronze-on-steel deposition with blue light high-speed Laser Cladding and IR Laser Cladding, properties and differences

Abstract

Laser cladding could replace casting as a productive and efficient way to deposit lead-free bronze on steel. Bronzes, however, mostly reflect IR wavelength, usually used in LC. Therefore, bronze melting requires high powers, which can excessively heat the substrate, potentially leading to quality issues. Using blue light high-speed laser cladding (B-HSLC) can improve bronze light absorption and lower the heat input to the substrate, as most of the energy is coupled directly into the powder which is melted in flight. This work compares bronze-on-steel coatings made by IR laser cladding (IR-LC) and B-HSLC. B-HSLC coatings were produced with a higher single-layer surface deposition rate and a lower power input than IR-LC coatings. Microstructural appearance was assessed through optical and electronic microscopy. The B-HSLC samples displayed better quality, comparable dilution, and extremely reduced heat impact on the substrate. B-HSLC represents an effective alternative for lead-free bronze depositions on dissimilar substrates.