Abstract:

2205 duplex stainless steels containing 0.07% and 0.01% Ag were respectively prepared by adding Cu-Ag alloy particles. Meanwhile, the base material 2205 and Cu-bearing 2205 were prepared for comparison with Ag-bearing 2205. The microstructure, mechanical properties, corrosion resistance and antibacterial properties of the four materials were investigated by Optical Microscope(OM), Scanning Electron Microscope(SEM), tensile test, electrochemical workstation and film mulching method. Results reveale that the increase of Ag content increases the amount of α phase and decreases the amount of γ phase in the microstructure. Ag-containing phases exist in both Ag-containing materials. Ag-phases with particle sizes ranging from 1 to 6 μm are distributed at the interface of α matrix and in α/γ phase, while Ag-phases with particle sizes ranging from 80 to 400 nm are distributed in γ phase. Compared with base material 2205, adding of Cu can improve the tensile strength of the materials, but decrease its elongation. The tensile strength and elongation of the materials both increase with the Ag content. The material containing 0.1% Ag exhibits the best comprehensive mechanical properties. In 3.5% NaCl medium, Cu-bearing 2205 exhibits the best corrosion resistance. With the increase in Ag content, the stability and corrosion resistance of passivation film first increases and then decreases. The antibacterial rate of Ag-bearing 2205 materials increases with the contact time. The high Ag-bearing materials exhibit a good antibacterial property, and the base material 2205 and Cu-bearing 2205 do not have antibacterial properties.

Key words: material synthesis and processing technology, Ag-bearing 2205 duplex stainless steel, Ag-bearing phase, mechanical properties, corrosion resistance, antibacterial property