SUS 304 STAINLESS STEEL MATERIAL

304 stainless steel, which has a density of 7.93g/cm3, is a typical type of stainless steel. It is sometimes referred to as 18/8 stainless steel in the industry because it contains more than 18% chromium and more than 8% nickel. 800°C high temperature resistance, excellent processing performance, high toughness, and widespread usage in the food, medicinal, industrial, and furniture decoration industries. However, it should be noted that the content index for food grade 304 stainless steel is stricter than that of regular 304 stainless steel. For instance, the international definition of 304 stainless steel is primarily composed of chromium 18%-20% nickel 8%-10%, but food grade 304 stainless steel is composed of chromium 18% and nickel 8%, allows a specific range of fluctuations, and limits the concentration of certain heavy metals. In other words, 304 stainless steel need not be of the food grade variety.

In the market, common labeling techniques include 06Cr19Ni10 and SUS304, where 06Cr19Ni10 generally denotes manufacture to national standards, 304 generally denotes production to ASTM standards, and SUS304 generally denotes production to Japanese standards.

A type of universal stainless steel called 304 is frequently used to produce equipment and parts that have good all-around performance (corrosion resistance and formability). Steel must include at least 8% nickel and 18% chromium to preserve the intrinsic corrosion resistance of stainless steel. A type of stainless steel manufactured in accordance with ASTM specifications is called 304 stainless steel.

Physical property

Tensile strength σb (MPa)≥515-1035

Conditional yield strength σ0.2 (MPa)≥205

Elongation δ5 (%)≥40

Hardness: ≤201HBW;92 HRB or less;210 hv or less

Density (20℃, g/cm³) : 7.93

Melting point (℃) : 1398~1454

Specific heat capacity (0~100℃, KJ·kg-1K-1) : 0.50

Thermal conductivity (W·m-1·K-1) : (100℃) 16.3, (500℃) 21.5

Linear expansion coefficient (10-6·K-1) : (0~100℃) 17.2, (0~500℃) 18.4

Resistivity (20℃, 10-6Ω·m2/m) : 0.73

Longitudinal modulus of elasticity (20℃, KN/mm2) : 193

Product standard

The Ni element is a crucial component of stainless steel 304 and has a direct bearing on both the material's price and corrosion resistance.

Ni and Cr are the two most significant components in 304, albeit they are not the only ones. Product standards outline certain requirements. According to industry consensus, 304 stainless steel can be defined as having Ni content greater than 8% and Cr content larger than 18%. Because of this, this kind of stainless steel is referred to as 18/8 stainless steel in the industry. In actuality, there are minor variances in the applicable product standards for different forms of stainless steel and very clear rules for 304.Some typical product standards and tests are listed below.

If a material doesn't comply with the specifications for each component of the product standard, it cannot be referred to as 304 stainless steel .

1、ASTM A276（Standard Specification for Stainless Steel Bars and Shapes）

2、ASTM A240（Chromium and Chromium-Nickel Stainless Steel Plate,Sheet, and Strip for Pressure essels and for General Applications）

3、JIS G4305（cold-rolled stainless steel plate, sheet and strip）

4、JIS G4303 （Stainless steel bars）

The above four standards are only a few common standards. In fact, 304 is not the only one mentioned in ASTM and JIS.Each standard actually has different requirements for 304, so to determine whether a material is 304, the accurate expression should say whether it meets the requirements of 304 in a product standard.Material certificate generally to issue the following types of reports:

Detailed comparison of standard specifications: 

Scope of application

The most popular chrome-nickel stainless steel is 304, which has good mechanical, corrosion, and heat resistance capabilities as well as being the strongest at low temperatures. Heat treatment hardening does not occur during stamping, bending, or other hot processing (using temperature range of -196°C to 800°C). If the atmosphere is industrial or extremely contaminated, corrosion resistance in the atmosphere must be cleaned promptly to prevent corrosion. Ideal for processing, storing, and moving food. It can be worked with and welded well. Bellows, a plate heat exchanger, cabinets, indoor pipelines, water heaters, boilers, and bathtubs are examples of domestic items. Other examples include medical equipment, building supplies, chemicals, food industry, agricultural, and marine parts..The content of 304 stainless steel is strictly controlled, which can also be called food grade 304 stainless steel

The majority of the standards focus on keeping the building's original appearance for an extended period of time. The most important factors in choosing the type of stainless steel are the necessary aesthetic requirements, the corrosion of the site of the atmosphere, and the cleaning system to be employed. Yet, other applications increasingly simply look for impermeability or structural integrity. For instance, the side walls and roofs of commercial structures. Even though the surface is not extremely clean, in many instances the owner's building cost may be more significant than aesthetics. 304 stainless steel performs admirably in dry indoor settings. Yet, if it wants to keep up its appearance outside in urban and rural locations, it must wash frequently. In heavily polluted industrial areas and coastal areas, the surface can be very dirty and even rust.

However stainless steel containing nickel is required to create the desired visual appearance in an outdoor setting. As a result, 304 stainless steel is frequently used for curtain walls, side walls, roofs, and other architectural reasons. Nevertheless, 316 stainless steel works best in environments where there is a substantial risk of industrial or marine erosive environments. People now fully understand the benefits of using stainless steel in structural applications. Stainless steel grades 304 and 316 are mentioned in various design specifications. The "duplex" stainless steel 2205 is also included in the European recommendations because it combines good atmospheric corrosion resistance with high tensile strength and elastic limit strength. In actuality, stainless steel is produced in all common metal shapes and sizes, in addition to a wide variety of unique shapes.  Steel sheet and strip are the most often used materials, along with medium and thick plates for special products such hot rolled structural sections and extruded structural sections. Together with other product types including profiles, bars, wires, and castings, seamless steel pipe is also available in round, oval, square, rectangular, and hexagonal shapes.