What is 304 stainless steel?
AISI 304 stainless steel designates the first commercially available stainless steel grade. It belongs to the group of V2A steels, under which chromium nickel steel grades are summarized. It is the main representative of this group, and in some cases the terms 304 and V2A are also used synonymously. In European norm, it is specified under the number 1.4301. Its alloy code is X5CrNi18-10. It is known for its combination of corrosion resistance and good mechanical properties. It belongs to the group of austenitic steel grades.
Furthermore, it is the most widely used stainless steel alloy in the world today, accounting for one-third of total production.
Properties of 304 stainless steel
304 is characterized by its good weldability with electrical processes. Even without heat treatment, the steel is corrosion resistant, due to its low carbon content. For maximum corrosion resistance, however, post-weld treatment may be required. The carbon content must be below a percentage of 0.08, although values below 0.05% are now common in practice. It also has very good polishability and can be flexibly shaped. It is approved for temperature stresses up to 600 °C. Its high-quality appearance is also appreciated, especially in the polished state.
Summary of 304 Stainless Steel Properties
- Excellent Weldability: Easily welded using electrical processes.
- Corrosion Resistance: Naturally resistant to corrosion due to low carbon content; enhanced with post-weld treatments.
- Low Carbon Content: Carbon content is kept below 0.08%, with values below 0.05% becoming increasingly common.
- High Polishability: Offers a high-quality, polished appearance.
- Flexible Shaping: Can be shaped flexibly for various applications.
- Temperature Resistance: Suitable for use under temperature stresses up to 600 °C.
- Aesthetic Appeal: Valued for its high-quality appearance in polished form.
Variations of 304-grade stainless steel
304 is characterized by a chemical composition of 18 % of chromium, a nickel content of 8 %, and a maximum of 0.08 % of carbon. Variations of this grade differ in the amount of carbon.
304L
304L is the low carbon version of 304 and is restricted to a maximum of 0.03 % of carbon. This alloy does not need post-weld annealing. The material 304L is easy to polish and deep-draw. It is mainly used in the chemical, petroleum, petrochemical and automotive industries and for heavy gauge components.
304H
304H is characterized by a higher carbon content between 0.04 and 0.1 %. Therefore, it retains its strength at elevated temperatures. Further, it retains aqueous corrosion resistance at temperatures between 500° C and up to 800° C.
Applications of 304
304 has a wide range of applications. It is particularly useful when resistance in environments such as water, moisture or weak acids is required. It is used, among other things, in the construction of fittings, food industry, pharmaceutical industry or in mechanical engineering. Typical products for end consumers are, for example, pots or sinks.
Here are additional applications highlighting the widespread utility of 304 stainless steel:
- Architectural Panels and Railings: Its aesthetic appeal and corrosion resistance make it ideal for exterior and interior architectural features.
- Automotive Components: Used in automotive trim and exhaust systems due to its durability and resistance to corrosion.
- Medical Devices: Preferred for medical devices and surgical instruments because of its easy sterilization and corrosion resistance.
- Marine Hardware: Chosen for marine environments for its resistance to salt water corrosion.
- Chemical Containers: Utilized in the manufacture of tanks and containers for chemicals due to its resistance to a wide range of substances.
- Brewery and Dairy Equipment: Its resistance to organic acids and cleaning solutions makes it suitable for brewery tanks and dairy processing equipment.
- Water Treatment and Plumbing Systems: Employed in water treatment facilities and plumbing systems for its resistance to corrosion and water.
- Kitchen Appliances and Countertops: Valued for its hygienic properties and modern appearance in kitchen environments.
- Outdoor Grills and Equipment: Used in outdoor grills and cooking equipment due to its high temperature resistance and durability.
Hardening of 304
While 304 stainless steel is highly valued for its versatility and excellent polishability, it encounters limitations under certain conditions, such as a predisposition towards cold welding. A robust solution to this challenge is offered by the BORINOX® method, a specialized process developed by BorTec. This innovative approach not only enhances the hardness of the steel, thereby mitigating the risk of cold welding, but it also maintains the alloy’s inherent advantages, including its corrosion resistance. The BORINOX® process exemplifies how BorTec’s advanced technologies can elevate the performance of 304 stainless steel beyond its natural capabilities, ensuring it meets the rigorous demands of diverse applications.
For industries requiring further enhancements in wear resistance, Bortec’s portfolio of services, including BORINOX®, provides tailored solutions to strengthen materials like 304 stainless steel. This steel, known for its relative softness, can significantly benefit from the hardening capabilities of BORINOX®, particularly when an increase in scratch resistance is essential.
Explore more about BorTec’s cutting-edge services and how they can optimize your materials:
