The Ability of Antibacterial Stainless Steel
Antibacterial stainless steel uses stainless steel as a carrier, and some antibacterial metal elements are added as an antibacterial agent to make it have both corrosion resistance and excellent antibacterial properties of stainless steel. According to different manufacturing methods, antibacterial stainless steel is roughly divided into surface-coated antibacterial stainless, composite antibacterial stainless steel plate, surface modified antibacterial stainless steel, and alloy type antibacterial stainless with antibacterial metal elements. This article mainly introduces alloy-type antibacterial stainless which is widely used.
alloy type antibacterial stainless is made by adding antibacterial metal elements during steelmaking, and then undergoing special heat treatment so that the antibacterial stainless is evenly distributed from the surface to the inside of the precipitation phase of the antibacterial elements. According to the addition of antibacterial metal elements, it can be divided into copper-containing or silver-containing antibacterial stainless steel.
Copper-containing antibacterial stainless is added with a certain amount of copper more than conventional stainless steel during the smelting process, and then the stainless steel is subjected to special heat treatment so that the stainless steel matrix is evenly dispersed and distributed with copper precipitates that can produce good antibacterial effects. In the 1990s, Japan’s Nisshin Steel Corporation first successfully developed copper-containing ferritic antibacterial stainless steel, copper-containing martensitic antibacterial stainless steel, and copper-containing austenitic antibacterial stainless. Among them, the copper-containing ferritic antibacterial stainless has a good antibacterial effect on various bacteria, especially the sterilization rate of Staphylococcus aureus, Escherichia coli, and green membrane bacteria is as high as 99% to 100%.
The preparation process of silver-containing antibacterial stainless steel is different from that of copper-containing antibacterial stainless steel. It does not require special antibacterial heat treatment to ensure its antibacterial properties. Silver is a metal element with strong antibacterial properties, about 100 times that of copper. Adding a small amount of silver can make stainless steel have good antibacterial properties. However, the production of silver-containing stainless steel is difficult to control the stainless steel smelting process.
By adding alloys during the smelting process of stainless steel, Baosteel obtained silver-containing antibacterial stainless steel with excellent serviceability and antibacterial performance, and thus proposed another effective method to solve the smelting problem of silver-containing antibacterial stainless steel.
In recent years, Baosteel has also been actively researching and developing antibacterial stainless steels and has applied for a number of invention patents. In early 2009, it successfully realized the industrialized mass production of copper-containing ferritic antibacterial stainless steels and introduced the cold and hot ferritic antibacterial stainless steels. The rolled plate product has excellent antibacterial properties, and its various performances reach or exceed the same type of conventional stainless steel.
The preparation methods of antibacterial stainless have their own advantages and disadvantages, but they have high requirements for production equipment and preparation technology, which makes it difficult to achieve mass production, and the cost is relatively high. In addition, during the deep processing and use of the product, the antibacterial layer on the surface is easy to wear and fall off, and the antibacterial property is lost. Therefore, it is not suitable for use in high friction places, and the fall off of the antibacterial layer will damage the smoothness and cleanness of the stainless steel surface.
Alloy-type antibacterial stainless has antibacterial metal elements added to the whole matrix, although it increases the manufacturing cost, it has good antibacterial properties and maintains excellent antibacterial properties after abrasion. Its production process is similar to that of ordinary stainless steel and can be produced in larger sizes. And complex-shaped plates, wires, tubes, etc., can also be processed into products with complex structures, and the future market prospects are better.
Advantages of alloy-type antibacterial stainless products: Good sterilization effect on common bacteria such as Escherichia coli and Staphylococcus aureus; it maintains good antibacterial performance after long-term use and surface wear; it is fully compatible with food safety and human safety Relevant technical standards; mechanical, corrosion resistance, cold and hot processing, welding and other properties are basically equivalent to the original steel; compared with conventional stainless steel, the cost of copper-containing antibacterial stainless steel increases by about 10% to 20%, and the cost of silver-containing antibacterial stainless increases by about 20%. % To about 40%.
In recent years, antibacterial stainless has been used in tableware, home appliances, the food industry, medical equipment, etc., and its future development and application prospects will be very broad.