Learn about the use of stainless steel in construction 　　

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What is stainless steel? The main alloying elements of stainless steel are chromium, molybdenum, nickel, and nitrogen. Chromium forms a passivating chromium oxide protective film, and the corrosion resistance of stainless steel stems from this surface oxide film. It is a ferritic stainless steel containing FeCr; examples of such steel grades include 430-type stainless steel ； Nickel stabilizes austenite, endowing it with ductility, toughness, and weldability; it is used to create austenitic stainless steels such as 304 stainless steel ； Molybdenum provides resistance to pitting and crevice corrosion; it is suitable for marine environments as well as industrial atmospheric conditions, with steel grades such as 316 stainless steel ； Nitrogen also provides stability to austenite, resistance to pitting and crevice corrosion, as well as improved strength properties; examples of steel grades include 2205 duplex stainless steel. 　　 Why is stainless steel used in construction? One reason is to meet the needs of modern society: it enhances the value of a product. The unique design or appearance of stainless steel allows it to occupy a specific position in the market. It requires minimal maintenance or refurbishment costs. Stainless steel also has the least impact on the environment during manufacturing, use, and disposal, and it can help increase profits as well. In terms of the properties of stainless steel itself: it is corrosion-resistant, does not require painting, has a high-quality appearance, comes in a variety of surface finishes and styles, possesses high strength, is easy to manufacture and weld, can be shaped into various complex forms, and can also be recycled 100%. Stainless steel is sometimes the most cost-effective option, usually with higher initial costs but lower life-cycle costs. 　　 The stainless steel grades used in construction and structures include: ferritic, austenitic, and duplex (ferritic-austenitic). Unlike carbon steel, stainless steel rarely fails due to uniform corrosion; if it does fail, it is as a result of localized corrosion, such as pitting and crevice corrosion. In construction, failure is usually of an aesthetic nature rather than structural, and a corrosion allowance is meaningless in this case. Technical considerations for stainless steel include: in terms of design, simple shapes should be used to facilitate cleaning; gaps should be avoided to prevent dirty water from splashing; cleaning access points should be incorporated; and adverse galvanic effects (contact between dissimilar metals) must be prevented ； Secondly, regarding the choice of steel grade, 430 or 304 is generally used for internal applications; for external applications where the requirements are not as strict (in rural areas), 316 can be used. In harsh marine or industrial environments, smooth 316 stainless steel that requires frequent cleaning is employed, as well as steel grades with higher alloy contents such as 317 stainless steel, 2205 duplex stainless steel, and 6% Mo stainless steel.