304 

 304 chemical grade for 0Cr19Ni10 17% chromium, 8% nickel. 304 is the most widely used stainless steel, heat-resistant steel. Equipment used in food production, general chemical equipment and nuclear energy. 304 stainless steel chemical composition specifications C Si Mn PS Cr Ni (Ni) Mo stainless steel SUS304 density of 7.93 g / cm 3 SUS304 chemical composition of ≤ 0.08 ≤ 1.00 ≤ 2.00 ≤ 0.05 ≤ 0.03 18.00-20.00 10.50 8.00 - - 
 Product Standards 
 For 304 stainless steel 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 provided by the product standards. Industry as long as the common determination of Ni content greater than 8%, Cr content greater than 18% can be considered to be 304 stainless steel. This is why the industry would call this type of stainless steel 18 / 8 stainless steel reasons. In actual fact, the relevant product standard 304 has a very clear requirement, and these product standards for different shapes of stainless steel have some differences. Here are some common product standards and testing. 
 304 to determine 
 To identify a material is 304 stainless steel, the product must meet the standards requirements of each element, as long as a does not meet, can not be called 304. 1, ASTM A276 (Standard Specification for Stainless Steel Bars Bars and Shapes profile) 304 C Mn PS Si Cr Ni 
 Requirement,% 0.08 2.00 0.045 0.030 1.00 18.0-20.0 8.0-11.0 
 2, ASTM A240 (Chromium and Chromium-Nickel Stainless Steel Plate Plate, Sheet Sheet, and Strip Strip for Pressure essels and for General Applications) 304 C Mn PS Si Cr Ni N 
 Requirement,% 0.07 2.00 0.10 0.045 0.030 0.075 17.5-19.5 8.0-10.5 
 3, JIS G4305 (cold-rolled sheet cold-rolled stainless steel plate, sheet sheet and strip strip) SUS 304 C Mn PS Si Cr Ni 
 Requirement,% 0.08 2.00 0.045 0.030 1.00 18.0-20.0 8.0-10.5 
 4, JIS G4303 (Stainless steel bars stainless steel bars) SUS 304 C Mn PS Si Cr Ni 
 Requirement,% 0.08 2.00 0.045 0.030 1.00 18.0-20.0 8.0-10.5 
 These four criteria are common to several standards, in fact, ASTM and JIS have mentioned more than 304 of these standards. In fact, each standard has different requirements for the 304, so in order to determine a material is not 304, correct expression should be a product that meets the requirements of the standard 304, the material certificates generally issued the following report types: 
 304 stainless steel SGS Report 
 Performance 
 System Description: 304 stainless steel is the most widely used of a chrome - nickel stainless steel with good corrosion resistance, heat resistance, low temperature strength and mechanical properties. Corrosion in the atmosphere, the atmosphere or if it is heavily polluted industrial areas, the need for timely clean to avoid corrosion. Suitable for food processing, storage and transportation. Has good processing properties and weldability. Plate heat exchanger, corrugated tube, household goods, building materials, chemical, food industry. 304 stainless steel for the state approved food grade stainless steel. 

 Larger standard 304 stainless steel 
 International Society of stainless steel marking method is to use the United States to mark a variety of standard three-digit level of malleable stainless steel. Including: ① austenitic stainless steel with 200 and 300 series digital mark, ② ferritic and martensitic stainless steel 400 series with a digital representation. For example, some of the more common austenitic stainless steel is 201, 304, 316 and 310 for the mark, ③ ferritic stainless steel is 430 and 446 for the tag, and 440C martensitic stainless steel is 410,420 for the mark, phase (austenite - ferrite), ④ stainless steel, precipitation hardening stainless steel and iron content of less than 50% of high-alloy is usually named using proprietary name or trademark. 4). Standard Classification and grading 4-1 grade category: ① the national standard GB ② industry standard YB ③ ④ local standard enterprise standard Q / CB 4-2 Category: ① ② product standard method of standard packaging standard ③ ④ basic standards 4-3 standard level (three levels): Y-class: the international advanced level I: the general level of international class H: advanced level national standard GB1220-2007 4-4 stainless steel rods (I grade) GB4241-84 stainless steel welded plate Park (H-level ) GB4356-2002 stainless steel welded plate garden (I grade) GB1270-80 stainless steel pipe (I grade) GB12771-2000 stainless steel pipe (Y class) GB3280-2007 stainless steel cold plate (I grade) GB4237-2007 stainless steel hot plate (I-level ) GB4239-91 stainless steel cold strip (I level) physical properties 304 
 Tensile strength σb (MPa) ≥ 520, the conditions yield strength σ0.2 (MPa) ≥ 205, elongation δ5 (%) ≥ 40, Reduction of ψ (%) ≥ 50, Hardness: ≤ 187HB; ≤ 90HRB; ≤ 200HV