304 stainless steel is a very common, the industry also known as 18/8 stainless steel. Its corrosion resistance is better than 430, but the price surpasses 316 cheaper, it is widely used in life, for example: some of the high-grade stainless steel cutlery, outdoor stainless steel railings. [1] While this stainless steel in the country is very common, but "304" this call has come from the United States. Many people think that 304 is a Japanese model called, but strictly speaking, a formal call on 304 stainless steel in Japan is "SUS304". Currently on the market there is a common method of labeling 06Cr19Ni10, 304, SUS304 three, including 06Cr19Ni10 generally expressed GB standards, ASTM standards generally represents 304, SUS304 marked JIS standard. 304 is a versatile stainless steel, it is widely used to produce good overall performance (corrosion resistance and formability) of equipment and parts. To maintain the inherent corrosion resistance of stainless steel, the steel must contain at least 16% chromium, 8% nickel content. 304 stainless steel is a grade produced in accordance with the ASTM standard stainless steel. 304 It is the equivalent of our 06Cr18Ni9 [GB / T 20878-2007 been changed to 06Cr19Ni10] stainless steel. Basic information SUS304 or 18/8 stainless steel. GB grades 0Cr18Ni9. SUS304 is Japan's JIS standard materials, is a Japanese series of austenitic stainless steel SUS. Equivalent to China's 0Cr18Ni9, 304 U.S. chemical composition Carbon C: ≤ 0.07 Si Si: ≤ 1.00 Chromium Cr :18.00-20 .00 Manganese Mn: ≤ 2.00 Ni-Ni :8.00-11 .00 Phosphorus P: ≤ 0.035 Sulfur S: ≤ 0.030 Density Density to 7.93 g/cm3 for 304 stainless steel product standards is a very important parameter directly determines its corrosion resistance, but also determines its value. 304 is the most important element of Ni, Cr, but it is not limited to these two elements. Specific requirements set by the product standards. Industry common judgment case as long as Ni content of more than 8%, Cr content greater than 18%, it can be considered a 304 stainless steel. This is why this type of stainless steel industry will be called 18/8 stainless steel reasons. In fact, the relevant product standard 304 has a very clear requirements and standards of these products have some differences for different shapes of stainless steel. Performance System Description: 304 stainless steel is the most widely used chromium - nickel stainless steel, with good corrosion resistance, heat resistance, low temperature strength and mechanical properties. Corrosion in the atmosphere, if it is heavily polluted industrial atmosphere or region, you need to keep clean to avoid corrosion. Suitable for use in food processing, storage and transport. Has good processing properties and weldability. Plate heat exchanger, bellows, household goods, building materials, chemical, food industry and so on. 304 stainless steel is a nationally recognized food-grade stainless steel. International standard method of the American Iron and Steel Institute of stainless steel is marked with three numbers to mark a variety of standard grade wrought stainless steel. Of which: ① austenitic stainless steel with 200 and 300 series digital mark, ② ferritic and martensitic stainless steel with 400 series numbers. For example, some of the more common austenitic stainless steel is 201, 304, 316 and 310 marks, ③ ferritic stainless steel is marked 430 and 446, 410, 420 and 440C martensitic stainless steel is marked, ④ duplex (austenitic - ferritic), stainless steel, precipitation hardening stainless steel and high-alloy iron content of less than 50% usually uses proprietary name or trademark name. 4). Standard classification and grading 4-1 hierarchical classification: ① National Standard GB ② industry standard YB ③ ④ local standard enterprise standard Q / CB 4-2 Category: ① ② Packaging Products Standard Standard Standard ③ ④ basic standard method standard level 4-3 (of three): Y class: the international advanced level Class I: International general level H level: advanced level 4-4 GB GB1220-2007 stainless steel bar (I grade) GB4241-84 stainless steel welded plate Park (H level) GB4356 -2002 stainless steel welded plate Park (I-level) GB1270-80 stainless steel pipe (I class) GB12771-2000 stainless steel pipe (Y class) GB3280-2007 stainless steel cold (I grade) GB4237-2007 stainless steel hot plate (Class I) GB4239- 91 stainless steel cold strip (Class I) physical properties of tensile strength σb (MPa) ≥ 520 Conditions yield strength σ0.2 (MPa) ≥ 205 Elongation δ5 (%) ≥ 40 Reduction of area ψ (%) ≥ 60 Hardness: ≤ 187HB; ≤ 90HRB; ≤ 200HV 304 stainless steel rust reason rusting occurs, there may be several reasons: the presence of chloride ions chloride ions widespread, such as salt / sweat / sea / sea / soil, and so on. Stainless steel in the presence of chloride ions in the environment, the corrosion rapidly, even more than the ordinary low carbon steel. Therefore, the use of stainless steel environment requirements, and require frequent cleaning to remove dust, keep it clean and dry. (So ??that you can give him set a "misuse.") The United States has an example: a company with an oak containers of chlorine ions in a solution, the container has been used hundreds of years, plans to replace the nineties due to lack of modern oak material, the use of stainless steel replacement 16 days after the vessel due to corrosion leaks. No solution treated alloy elements dissolved substrate, resulting in tissue matrix alloy content is low, poor corrosion resistance. Intergranular corrosion of this material does not contain titanium and niobium have a tendency to intergranular corrosion. Adding titanium and niobium, together with the stabilization process can reduce intergranular corrosion. Corrosive chemicals in the air or in a high-alloy steel resistant to corrosion, stainless steel is a beautiful surface and good corrosion resistance, without going through the plated surface treatment, and play inherent in surface properties of stainless steel, for use in multi- An aspect of steel, stainless steel is often called. Representative of the performance of 13 chrome steel, 18-8 chrome-nickel steel alloy. From the perspective of metallographic analysis, because the stainless steel contains chromium chromium film formed on the surface leaving a thin, the membrane separating the oxygen from corrosion-resistant steel intrusive role. To maintain the inherent corrosion resistance of stainless steel, the steel must contain more than 12% chromium. The need for welding applications. Lower carbon content makes it close to the weld heat affected zone to minimize carbide precipitation, and carbide precipitation may lead to intergranular corrosion of stainless steel in certain environments (welding erosion). Typical uses most of the requirements is to maintain long-term building of the original appearance. In determining when to choose the type of stainless steel, the main consideration is the aesthetic standards required by the system to be used to clean corrosive and location of the atmosphere. However, a growing number of other applications, or just looking for the integrity of the structure is not permeable. For example, industrial building roof and side walls. In these applications, the construction cost of the owner may be more important than the aesthetic, surface and to be very clean. 304 stainless steel using a dry effect is quite good indoor environment. However, in rural and urban areas in order to maintain their appearance in the outdoors, they need regular cleaning. In heavily polluted industrial areas and coastal areas, the surface will be very dirty and even rust. But to get the aesthetic effect of the outdoor environment, it requires the use of nickel-containing stainless steel. So, 304 stainless steel is widely used in curtain wall, side walls, roofs and other construction purposes, but in severe erosion of industrial or marine atmosphere, the best use of 316 stainless steel. Stainless steel sliding door now, it has been fully aware of the use of stainless steel in structural applications superiority. There are several design criteria included 304 and 316 stainless steel. Because "duplex" 2205 has already good atmospheric corrosion resistance and high tensile strength and elastic limit of integration, so the European guidelines also include the steel. In fact the shape of the product, stainless steel is the full shape and size of a standard metal manufacturing, and there are many special shapes. The most commonly used product is made of sheet and strip, and plate production with special products, for example, the production of hot-rolled structural steel and structural steel extrusion. And there are round, oval, square, rectangular and hexagonal welded or seamless steel tubes and other forms of products, including profiles, rods, wire and castings. As the surface condition discussed later, in order to satisfy aesthetic requirements architects have developed a variety of commercial surface processing. For example, the surface can be highly reflective or matte; may be glossy, polished or embossed; may be colored, the color of the plating or etching a pattern on the surface of stainless steel, etc. can be brushed, designers to meet the various requirements of the appearance. Surface state is easy to maintain. Just the occasional rinse can remove dust. Because of good corrosion resistance, graffiti can be easily removed or contaminated surfaces other similar surface contamination. Edit this paragraph etching etching processing methods and processing methods, is a protective film on the stainless steel surface color screen printing acid, ferrous chloride solution and then etched to form artistic patterns. Color spray method is spray painted in the screen printing method jet pigment particles constitute Lipi sample surface to form artistic patterns. Process [1] stainless steel spray process color art processing methods are: stainless steel etching → → → silk screen printing alkali treatment → → → coloring alkali treatment → finished. Stainless steel etching process is the art processing method: stainless steel screen → → → alkali etching treatment → → finished coloring. Stainless steel spray process color art processing methods are: stainless steel etching → → → silk screen printing alkali treatment → → → coloring alkali treatment → finished. Stainless steel chemical coloring, dyes and pigments is not used, but the stainless steel was immersed in concentrated sulfuric acid solution was warmed in chromium, chemical coloring, which is characterized with good resistance to food. This processing method in which ink is used, there must be a very strong acid, generally with the treatment process using UV-curing inks compatible with specific properties.