Stainless Steel Round Bar: Types and Properties

Stainless steel round bar is a versatile material that finds applications across various industries. With its corrosion resistance, durability, and unique aesthetic properties, it has become a go-to choice for a range of manufacturing and engineering needs. In this article, we delve into the different types of stainless steel round bars and their distinctive properties, highlighting their benefits and uses in various industries.

What’s stainless steel round bar?

SS round bar is also called stainless steel rod. It belongs to the category of long materials and also belongs to the category of rod materials. The so-called stainless steel round bar refers to a long material with a uniform circular cross section, generally about four meters long. It can be divided into bright round and black rod.

The so-called bright round refers to the surface that is smooth and processed by precise rolling; and the so-called black rod refers to the surface that is black and rough, directly hot rolled. It has excellent corrosion resistance and good corrosion resistance to alkali solutions, most organic acids, and inorganic acids. The stainless steel round bar has strong oxidation resistance and high strength at high temperatures; due to the addition of Mo element, the stainless steel round bar has a certain degree of austenite structure, and the grain refinement significantly reduces the effect of cold work hardening.

Stainless Steel Round Bars: Common Types and Properties

Common types of stainless steel round bars include 301, 304, 303, 316, 316L, 304L, 321, 2520, 201, 202, etc. They are denoted by diameter, such as “50”, indicating a round bar with a diameter of 50mm. Round bars are divided into hot-rolled, forged, and cold-drawn categories. The specifications for hot-rolled round bars range from 5.5-250mm.

1. 310S ss round bar.

Characteristics: 310S stainless steel is an austenitic chrome-nickel stainless steel with good oxidation resistance and corrosion resistance. Due to the high percentage of chromium and nickel, 310S has better creep strength, can work continuously at high temperatures, and has good high-temperature resistance.

2. 316L ss round bar.

Characteristics: The cold-rolled products have good appearance and aesthetics; excellent corrosion resistance due to the addition of molybdenum, especially excellent pitting resistance; excellent high-temperature strength; excellent processing quenching property (weak magnetic after processing); non-magnetic in solid solution state.

3. 316 ss round bar.

Characteristics: 316 stainless steel is the second most widely used steel species after 304, mainly used in food industries and surgical instruments. Due to the addition of molybdenum, it has excellent corrosion resistance, atmospheric corrosion resistance, and high-temperature strength, making it suitable for use in harsh conditions. Excellent processability (non-magnetic).

4. 321 ss round bar.

Characteristics: Adding Ti to 304 steel to prevent intergranular corrosion, suitable for use at temperatures of 430℃-900℃. In addition to adding titanium to reduce the risk of welding corrosion, other properties are similar to 304.

5. 304L ss round bar.

Performance: 304L stainless steel round bar is a variant of low-carbon 304 stainless steel, used in welding applications. The lower carbon content results in less carbide precipitation in the heat-affected zone near the weld, which may lead to intergranular corrosion (weld corrosion) in some environments.

6. 304 ss round bar.

Characteristics: 304 stainless steel is a widely used chromium-nickel stainless steel with good corrosion resistance, heat resistance, low-temperature strength, and mechanical properties. It has good corrosion resistance in the atmosphere. If it is used in industrial atmospheres or heavily polluted areas, it needs to be cleaned regularly to avoid corrosion.

Treatment of Oxide Scale on Stainless Steel Round Bars

(1) Sandblasting (or shot blasting): This method mainly uses micro glass beads to remove the surface black oxide scale.

(2) Chemical method: Using a pollution-free pickling passivation paste and a cleaning solution with inorganic additives that are non-toxic at room temperature for immersion cleaning. This achieves the whitening treatment of the original color of the stainless steel. After processing, the appearance is basically non-reflective. This method is more suitable for large and complex products.

Corrosion of Stainless Steel Round Bars

The surface attached dust particles can promote corrosion of stainless steel. When surface dust particles exist, gaps are formed at the locations of dust deposition, which easily maintain water films containing chloride ions, preventing oxygen replenishment and leading to damage of the passive film. In addition, this dissolution zone and the adjacent passive zone form a closed circuit battery, which accelerates the formation and development of pitting corrosion pits.

Execution Standards for Stainless Steel Round Bars：

National standard for stainless steel round bars: GB/T14975-2002, GB/T14976-2002, GB/T13296-91

American standard: ASTM A312/A312M, ASTM A213/213A, ASTM A269/269M

Application Fields of Stainless Steel Round Bars

The application prospects of stainless steel round bars are broad, and they are widely used in building and decoration industries such as hardware, shipbuilding, petrochemicals, machinery, medicine, food, electricity, energy, aerospace, and more. They are also used in production equipment such as sea-water equipment, chemicals, dyes, paper making, oxalic acid, fertilizers, and more.

Conclusion

Thank you for reading our article and we hope it can help you to have a better understanding of the types and properties of stainless steel round bars. If you want to find more information about stainless steel round bars, we’d advise you to visit Sino Stainless Steel.

As a leading supplier of stainless steel products across the world, Sino Stainless Steel provides customers with high-quality stainless steel products such as stainless steel strips, stainless steel coils, stainless steel plates, stainless steel sheets, stainless steel bars, and stainless steel wires at a very competitive price.