Preparation and properties of Cu/Cu-Sn alloy cladding layers on titanium alloy by laser cladding

Titanium alloy is widely used in marine vessels and acoustic sounding equipment, but its application in ocean engineering is limited by marine biofouling. This can be addressed by applying a copper layer with strong adhesion and antimicrobial properties. However, integrating titanium and copper is challenging, and it is necessary to consider whether this combination will affect the sound transmission performance of acoustic sounding equipment when applied to its outer shell. In this study, pure Cu and Cu-Sn alloy (95 wt%Cu+5 wt%Sn) cladding layers were successfully synthesized on titanium alloy (TA3) surface using laser cladding with a 12000 W fiber laser. The process parameters included a laser scanning speed of 83.3-100.0 mm/s and a laser power of 1600-1820 W. The results show that the addition of Sn can improve the wettability between copper alloy powder and titanium alloy substrate. The bond strength of the Cu-Sn alloy cladding layer is 204.54 MPa, an 87.15 % increase compared to pure Cu (109.29 MPa). The quality of the cladding layer formation and the metallurgical bonding property were enhanced due to reduction of the formation of dendrite Ti-Cu brittle phases and the refined grain structure. Cu-Sn alloy cladding layers outperform pure Cu in sound transmission, with both coefficients exceeding 0.75. Laser cladding Cu-Sn alloy is more advantageous, which provides a novel strategy for the preparation of antifouling copper layers on titanium alloys applied to marine vessels and acoustic sounding equipment.