Stainless Steel 321H Properties

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Stainless Steel 321H Properties

Stainless Steel 321H is a high-carbon, heat-resistant alloy that plays a vital role in numerous industrial applications due to its superior resistance to oxidation and corrosion at high temperatures. Known for its excellent welding properties and good mechanical strength, Stainless Steel 321H is a preferred material in industries such as aerospace, chemical processing, and power generation. In this article, we explore how Ferrobend, a leading manufacturer of stainless steel products, produces and supplies Stainless Steel 321H, and why it stands out as an optimal choice for various applications. Stainless Steel 321H is an austenitic stainless steel alloy containing high levels of chromium and nickel, combined with titanium for stabilization. The primary difference between 321 and 321H is the higher carbon content in 321H, which gives it enhanced high-temperature strength. This variant is particularly designed to resist carbide precipitation in the heat-affected zone, making it ideal for use in high-temperature environments where stress and thermal stability are paramount.

At Ferrobend, we take pride in offering high-quality stainless steel products that meet the rigorous demands of industrial applications. Our manufacturing process for Stainless Steel 321H is optimized to provide superior performance in all aspects of its production, ensuring that our customers receive a product that delivers long-term durability and strength. Ferrobend is committed to providing excellent customer service and support throughout the purchasing process. From initial inquiries to post-sales assistance, we ensure that every step is seamless and efficient. Our customer service team is available to provide technical advice, assist with product selection, and answer any questions related to Stainless Steel 321H.

One of the key advantages of choosing Stainless Steel 321H from Ferrobend is its performance in extreme environments. With high corrosion and oxidation resistance, 321H is ideal for use in industries that require materials that can withstand prolonged exposure to high temperatures. Whether it's a gas turbine or a chemical reactor, 321H offers the durability needed to maintain operational integrity. Ferrobend’s Stainless Steel 321H is engineered for easy welding, making it a perfect choice for industries that require complex structures or assemblies. The alloy’s excellent welding properties allow for secure and durable joints, even in the most demanding applications. While Stainless Steel 321H might have a slightly higher initial cost compared to other alloys, its durability and resistance to wear, tear, and corrosion translate into long-term savings. For industries like power generation and chemical processing, where the cost of downtime or maintenance is substantial, using high-quality materials like 321H significantly reduces the risk of failure and maintenance expenses.

Chemical Properties:

Elements Cr Ni C Si Mn P S Mo Fe
% min: 17.0 ,max:19.0 min: 8.0 ,max: 10.0 0.15 max 1.00 max 2.0 max 0.20 max 0.15 min 0.75 balance

Mechanical Properties:

Tensile Strength ksi (min.) Yield Strength 0.2% Offset ksi (min.) Elongation - % in 50 mm (min.) Hardness (Brinell) MAX Hardness (Rockwell B) MAX
75 30 35 228 -

Physical Properties:

Denstiy lbm/in3 Coefficient of Thermal Expansion (min/in)-°F Electrical Resistivity mW-in Thermal Conductivity BTU/hr-ft-°F Melting Range
at 68 °F at 68 – 212°F at 68 – 932°F at 68 – 1450°F at 68°F at 212°F at 392°F at 752°F at 1112°F at 1472°F at 68 – 212°F -
0.29 9.2 10.4 10.9 28.3 30.7 33.8 39.4 43.7 47.6 113.2 2552°F

Equivalent Grades and Designations:

SAE / AISI 303
UNS S30300
EN Material Number 1.4305
EN Material Name X8CrNiS18-9
DIN Material Name X8CrNiS18-9
JIS SUS 303
BS 202S 21 En58M

Heat Resistance:

  • Good oxidation resistance at temperatures up to 1700oF (927 oC)
  • Continuous use at temperatures above 1400oF (760oC) is not usually recommended due to carbide precipitation which can lead to irregular scaling
  • Does not have a low carbon content so it is also vulnerable to sensitization

Welding Characteristics:

  • Not generally recommended, but may be welded with some difficulty
  • May be welded with Alloy 310 electrodes
  • Should be annealed after welding to re-dissolve precipitated carbides

Machinability:

  • High machining rates can be obtained in the annealed condition with hardness in the range of 200 to 240 Brinell
  • Will work harden; therefore, it should be machined at reduced surface feet per minute and heavier feeds to prevent glazing at the tool interface.

Applications:

  • Nuts and bolts
  • Aircraft fittings
  • Gears
  • Screws
  • Shafts
  • Electrical switchgear components
  • Bushings