Process And Properties Of Copper-Bearing Antibacterial Austenitic Stainless Steels

With the development of society and living standard of people, the people’s healthy consciousness rises. Due to the wide fatal infection incidents happened in recent years, antibacterial stainless steels were developed and have met the raised public awareness of hygiene. They have wide applications in many fields, such as food industry, hospitals, domestic appliances and public transportation. It is helpful for steel enterprises to be capable of preparing copper-bearing antibacterial austenitic stainless steel using actual stainless steel product line. Based on this objective, we studied the properties and microstructures of copper-bearing antibacterial austenitic stainless steels which have gone through different processes in this paper.In this paper, antibacterial stainless steels are prepared by vaccum melting, fogging, hot rolling and antibacterial heat treatment followed by cold rolling and short time annealing. Properties testing indicate that the materials exhibit both excellent antibacterial property and good corrosion resistance. In addition, this process can produce good surface quality and is suitable for actual stainless steel product line.Through investigation on relationship between composition and properties, good effects of copper were found. As copper content increases, the antibacterial property and corrosion resistance are improved. Therefore, it is better to increase the copper content in a certain range which does not affect hot formability. The addition of nitrogen can also improve antibacterial property and corrosion resisitance.The research on process shows that corrosion resistance increases sharply with the increase of solution treatment time when the solution treatment time is below 2min, while antibacterial property decreases slightly. Over 2min, corrosion resistance increases slightly but antibacterial property decreased sharply. Hence, in order to gain good properties, materials had better to be solution treated at 1050℃for 1~2min. TEM analysis indicates that carbides and copper based precipitates precipitate along defects at the same time, They form intergrowth precipitates.