Effect of Annealing Process on Microstructure and Properties of Tin Bronze/Steel Bimetallic

Tin bronze/steel bimetallic is a widely utilized industrial material in the field of sliding bearing applications. Arc cladding technology represents an emerging method for fabricating tin bronze/steel bimetallic materials; however, research on their microstructure and mechanical properties remains limited. This study investigates the microstructural characteristics and mechanical behavior of tin bronze/steel bimetallic materials produced via the arc cladding process, with particular emphasis on the effects of annealing treatment on these properties. The tin bronze layer consists of a fine-grained zone, a columnar dendritic zone, and a freely dendritic zone. The tin bronze/steel bimetallic material exhibits high mechanical strength and strong interfacial bonding. Nevertheless, during three-point bending tests, cracks are observed in the tin bronze layer. When annealed at temperatures ranging from 300 °C to 700 °C, the tensile strength, shear strength, and hardness of the material decrease, while the elongation increases significantly. Moreover, no cracking occurs during three-point bending tests. Upon reaching an annealing temperature of 800 °C, the overall mechanical performance deteriorates rapidly. An annealing temperature of 300 °C is identified as an optimal parameter for achieving favorable mechanical properties.