Understanding the Basics of Stainless Steel and its Applications
Stainless steel is a versatile and widely used material in various industries due to its unique properties and durability. Understanding the basics of stainless steel, including its composition and different grades, is essential for anyone working with or considering using this material.
One of the most commonly used stainless steel grades is SUS304. It is known for its excellent corrosion resistance, making it suitable for applications where exposure to moisture or harsh environments is expected. SUS201, on the other hand, offers lower corrosion resistance but has higher strength compared to SUS304.
The composition of stainless steel typically includes iron, chromium, and varying amounts of other elements such as nickel and molybdenum. These elements contribute to the material’s corrosion resistance, strength, and other desirable properties.
Different stainless steel grades are chosen based on their specific applications. For example, SUS304 is often used in kitchen appliances, food processing equipment, and architectural structures due to its hygienic properties and aesthetic appeal. Other grades may be preferred for applications requiring high temperature resistance or exceptional strength.
By understanding the basics of stainless steel composition and different grades available, individuals can make informed decisions about which type of stainless steel is best suited for their specific application needs. Whether it’s for construction projects or manufacturing processes, stainless steel continues to prove its versatility and reliability across various industries.
SUS304 is the most common stainless steel material with a density of 7.93 g/cm³; the main components are 18% chromium and 8% nickel, so it is also called 18/8 stainless steel, which means it contains more than 18% chromium and more than 8% nickel. ; High temperature resistance of 800°C, with good processing performance and high toughness. It is widely used in industry, furniture decoration industry, food and medical industry.
|11||ASTM A554-15a (MT-304)||0.08||2||0.045||0.03||1||18.0-20.0||8.0-11.0|
SUS201 stainless steel is a popular choice in various industries due to its unique composition and desirable properties. Understanding the composition and properties of SUS201 is crucial for engineers, manufacturers, and designers who rely on this material for their projects.
The composition of SUS201 stainless steel:
(C) Carbon: ≤0.15
(Si) Silicon: ≤0.75
(Mn) Manganese: 5.5～7.50
(Cr) Chromium: 16.0～18.0
(P) Phosphorus: ≤0.060
(Ni) Nickel: 3.5-5.5
See ASTM A666
The disadvantage of this material is that the chromium content below 18% cannot reach a balance with the low nickel content and ferrite is formed. For this reason, the chromium content in 200 series stainless steel is reduced to 13.5% to 15%. In some cases It has dropped to 13% to 14%, and its corrosion resistance cannot be compared with 304 and other similar steels. In addition, manganese and in some cases copper reduce the repassivation effect under the acidic conditions common in corrosion areas of deposits and crevices. 200 series steel destroys approximately 10-100 times faster than 304 stainless steel under these conditions. The residual sulfur and carbon content in these steels often cannot be controlled during production, and the materials cannot be traced, even during material recycling. If Cr-Mn steels are not accounted for, they become a dangerous scrap mix, resulting in castings containing unexpectedly high manganese content.
The difference between SUS304 and SUS201
1. Differences in chemical composition：
The compositions of 201 stainless steel and 304 stainless steel are different. Although both are chromium-nickel alloys, their specific compositions are different. The chromium content in 201 stainless steel is about 15%, while that in 304 stainless steel is 18%; similarly , the nickel content in 201 stainless steel is 5%, while 304 stainless steel contains more, about 9%; 201 stainless steel contains manganese, but 304 does not. Therefore, this also causes the appearance of the two to be different in color. The surface of 201 stainless steel is brighter, while the surface of 304 stainless steel has a matte effect.
2. The difference in corrosion resistance
Due to the different nickel content, the corrosion resistance of 201 stainless steel is not as good as that of 304 stainless steel, and the acid and alkali resistance of 201 stainless steel is not as good as that of 304 stainless steel. 304 stainless steel has good corrosion resistance to acid, alkaline solutions, high temperature oxidation and oxidizing chemicals; while the corrosion resistance of 201 stainless steel is significantly worse than 304 stainless steel and cannot withstand the corrosion of acidic solutions and seawater (under normal use , the corrosion resistance of SUS304 is more than 10 times that of SUS201).
3. The difference between strength and hardness
The strength and hardness of 304 stainless steel are better than 201 stainless steel. 201 stainless steel material is relatively soft and easier to process and manufacture than 304 stainless steel. 201 stainless steel can increase its strength and hardness after heat treatment, but its tensile strength and compressive strength are still weaker than 304 stainless steel. In addition, 304 stainless steel can increase its strength again after welding, but 201 stainless steel does not have this feature.
4. Differences in application fields
The corrosion resistance of 201 stainless steel is not high, but it has higher density and no pinholes inside, so it is suitable for dry environments. It is generally used in indoor decoration, such as decoration fields, industrial products, etc., and can meet the needs well. 304 stainless steel has better corrosion resistance, so it can be used in industry, home decoration, medical and other industries. It is also suitable for coastal or humid areas.
5. Price difference
Due to the complex composition of 304 stainless steel and the cumbersome manufacturing process, the price of SUS304 is twice as high as that of SUS201 stainless steel.
Summary: Although 201 stainless steel can be used in some fields that require processing and manufacturing, 304 stainless steel has obvious advantages in strength, hardness, corrosion resistance, surface treatment, etc. Therefore, we need to choose stainless steel materials according to specific usage scenarios and requirements.
How to identify the SUS201 & SUS304
When it comes to testing and identifying SUS201 and SUS304, the use of reagents is crucial. Reagents are substances or compounds that are added to a system to cause a chemical reaction or detect the presence of specific elements or compounds.
To test and identify SUS201 and SUS304, there are several reagents that can be used. One commonly used reagent is nitric acid. When nitric acid is applied to stainless steel, it reacts differently with SUS201 and SUS304 due to their varying chemical compositions.
When testing with nitric acid, SUS201 will show a strong reaction, resulting in the formation of a dark brown color. On the other hand, when applied to SUS304, nitric acid will produce a lighter or no reaction at all.
Another effective method to testing and identifying SUS201 and SUS304 is through the use of an XRF tester. This non-destructive testing technique allows for the analysis of the elemental composition of a material, making it ideal for identifying different stainless steel grades.
To begin the testing process, ensure that the XRF tester is calibrated and ready for use. Then, take a small sample or portion of the material being tested and place it in front of the XRF instrument.
Next, activate the XRF tester and direct its beam towards the sample. The instrument will emit high-energy X-rays that interact with the atoms in the material. As a result, characteristic fluorescent X-rays are emitted by each element present in the sample.
The XRF detector within the instrument will capture these fluorescent signals and convert them into measurable data. This data will then be analyzed by software within the device to determine which elements are present in the sample.
In order to identify whether a material is SUS201 or SUS304, compare its elemental composition to known standards for these stainless steel grades. SUS201 typically contains higher levels of manganese (Mn) compared to SUS304, while SUS304 has higher levels of chromium (Cr) and nickel (Ni).
By comparing these elemental concentrations obtained from your test sample with known standards for each grade, you can accurately identify whether it is SUS201 or SUS304.
Overall, utilizing an XRF tester provides a reliable and efficient method for testing and identifying different stainless steel grades such as SUS201 and SUS304.
What stainless steel material is used for water bottle from Ecoway Houseware
When it comes to choosing a stainless steel water bottle, the material used is of utmost importance. Ecoway Houseware understands this and ensures that their water bottles are made from high-quality stainless steel.
One of the commonly used stainless steel materials for water bottles is stainless steel 18-8, also known as SUS304. This particular grade of stainless steel is highly regarded for its durability, corrosion resistance, and ability to maintain the quality of the contents inside.
SUS304 stainless steel is widely recognized for its food-grade quality, making it a safe choice for storing beverages. It does not react with liquids or alter their taste, ensuring that your water remains fresh and pure.
Ecoway Houseware’s commitment to using SUS304 stainless steel in their water bottles highlights their dedication to providing customers with a reliable and long-lasting product. With this material, you can trust that your water bottle will withstand daily use and retain its quality over time.
Investing in a stainless steel water bottle from Ecoway Houseware means investing in a product that not only keeps your drinks at an optimal temperature but also prioritizes safety and durability. Choose Ecoway Houseware for a reliable and high-quality stainless steel water bottle experience.