Stainless Steel 321 / 321H Sheet & Plates

Suppliers, Traders, Exporters and Stockists of 321 Sheets & Plates, 321H Sheets & Plates

We at ARK Stainless are a supplier, stockist & trader of Stainless Steel 321-321h Sheets Plates in the Indian as well as international markets. We manufacture stainless steel sheets and plates in customised design using premium quality raw materials. We have an expert team that properly does their work and produce a high-quality product in terms of usability, reliability, and longevity. We offer a wide range of sheets and plates in a variety of sizes and dimensions. These products are subjected to various tests at each stage of production.

Features

• Corrosion resistant
• High tensile strength
• Dimensional accurate and Precise design

ASTM A240 321 Plate, Stainless Steel 321 is the stabilized version of Stainless Steel 304. The 18/8 blend of chromium and nickel is tempered with titanium to give type 321 protection from intergranular corrosion that can occur after heat treatment. It is protected from temperatures ranging from 800 to 1500° F. The metal displays high strength and resistance to various forms of corrosion, including that from aqueous environments. Type 321 finds application in heavy welding components, along with dynamic environments that are subject to changes.

However, the addition of titanium limits the application of 321 in terms of working. The metal is not recommended for certain welding techniques as it is not consumable. Beyond this, stainless steel 321 has excellent forming characteristics, does not require annealing after being welded, and displays toughness in a range of temperatures. The metal shows strength even when exposed to cryogenic temperatures. Additionally, it is often chosen over Type 304 for its increased resistance to creep and rupture. Both metals may be susceptible to stress corrosion cracking.

Stainless Steel 321H is the higher-carbon modification of stainless steel 321. In addition, 321H is stabilized by an addition of niobium to resist intergranular corrosion. It is also able to withstand higher temperatures than type 321, due to its elevated carbon levels. While 321H displays the same welding and forming characteristics of type 321, the metal cannot be hardened by heat treatment. It is utilized in situations where type 321 cannot withstand the high temperatures, typically those exceeding 1000° F. Type 321H displays better resistance against creep than both 321 and 304 stainless steels.

321H also shows resistance against acid corrosion in a variety of environments. Lower temperatures provide better resistance, but the metal can withstand up to a 10% acid solution, that has been diluted, at elevated temperatures. However, the metal shows very little resistance against chlorine or sulfuric solutions at any given temperature.

Given their similar composition and characteristics, it is possible for stainless steels 321 and 321H to become dually certified.

What is the difference between 321 and 321H stainless steel sheet & plate?

321 and 321H stainless steel sheet / plate offer different levels of strength and corrosion resistance. 321 is a non-heat treatable type of stainless steel that is typically used for applications that require weldability and toughness. On the other hand, 321H is a heat-treated version of 321 stainless steel that exhibits higher strength at elevated temperatures and offers better formability. It's often used in more demanding environments where its ability to withstand high temperatures makes it a preferred choice. Ultimately, selecting the correct grade for an application will depend upon the application's requirements regarding temperature, strength, corrosion resistance, and formability.

What is 321 stainless steel sheet/plate made of?

321 stainless steel sheet/plate is an alloy composed of chromium, nickel, and titanium and has excellent corrosion resistance as well as heat resistance. It is a preferred choice for high-temperature applications because it won't distort or harden in extreme temperatures. The high chromium and titanium content also gives 321 stainless steel its unique design and aesthetic that is attractive for indoor or outdoor applications. This premium grade of steel has been used by a variety of industries, including aerospace, to enable complex projects that require strength, precision, and durability.

Specifications of Stainless Steel 321 & 321H Sheets/Plates

• Standard : 321 / 1.4541
• Size : 1/4" to 4"
• Finish : Cold rolled sheet (CR), 2B, 2D, BA NO(8), Hot rolled plate (HR), SATIN (Met with Plastic Coated)
• Thickness: 4.0mm - 100mm
• Form: Coils, Foils, Rolls, Plain Sheet, Shim Sheet, Perforated Sheet, Chequered Plate, Strip, Flats, Blank(Circle), Ring(Flange)
• Hardness : Soft, Hard, Half Hard, Quarter Hard, Spring Hard etc.

Stainless Steel 321 and 321H

Stainless Steel 321 and 321H are austenitic stainless steels that are stabilized with titanium, which makes them resistant to sensitization and intergranular corrosion. While they share many similarities, the main difference between the two is the carbon content. Stainless Steel 321H has a higher carbon content compared to 321, making it suitable for high-temperature applications. Here are some key features of Stainless Steel 321 and 321H sheet and plate.

Corrosion Resistance

• Exhibits excellent corrosion resistance, particularly against acidic and chloride-containing environments.
• Resistant to intergranular corrosion due to the addition of titanium.

Heat Resistance

• Maintains good performance at elevated temperatures.
• Suitable for high-temperature applications, making it useful in industries such as aerospace, chemical processing, and petrochemical.

Stabilization

• Stabilized with titanium to prevent sensitization during welding, which can lead to intergranular corrosion.

Formability

• Exhibits good formability and can be easily welded and fabricated.

Strength

• Possesses good strength and toughness, making it suitable for structural applications.

Higher Carbon Content

• Stainless Steel 321H has a higher carbon content compared to 321, which improves its high-temperature strength.

Creep Resistance

• The higher carbon content in 321H provides enhanced creep resistance, making it suitable for applications involving prolonged exposure to elevated temperatures.

Applications

Chemical Processing

• Used in chemical processing equipment where corrosion resistance is crucial.

Aerospace

• Commonly employed in aerospace applications due to its high-temperature stability.

Petrochemical Industry

• Widely used in the petrochemical industry for equipment such as pressure vessels and piping systems.

Heat Exchangers

• Suitable for manufacturing heat exchangers and similar equipment.

High-Temperature Environments

• Well-suited for applications requiring resistance to high temperatures, such as furnace components and exhaust systems.

Surface Finishes

Cold Rolled or Hot Rolled

• Available in both cold-rolled and hot-rolled forms.

Polished or Mill Finish

• Can be supplied with a polished surface finish or in a mill finish.

Standards and Specifications

• ASTM A240 : Common specification for chromium and chromium-nickel stainless steel plate, sheet, and strip.
• ASME SA240 : ASME standard that covers the same scope as ASTM A240.

Composition ranges for 321 grade stainless steel Sheets & Plates

Grade		C	Mn	Si	P	S	Cr	Mo	Ni	N	Other
321	min. max	- 0.08	2.00	0.75	0.045	0.030	17.0 19.0	-	9.0 12.0	0.10	Ti=5(C+N) 0.70
321H	min. max	0.04 0.10	2.00	0.75	0.045	0.030	17.0 19.0	-	9.0 12.0	-	Ti=4(C+N) 0.70

Mechanical properties of 321 grade stainless steel Plates & Sheeets

Grade	Tensile Strength (MPa) min	Yield Strength 0.2% Proof (MPa) min	Elongation (% in 50mm) min	Hardness
				Rockwell B (HR B) max	Brinell (HB) max
321	515	205	40	95	217
321H	515	205	40	95	217

Physical properties of 321 grade stainless steel in the annealed condition

Grade	Density (kg/m3)	Elastic Modulus (GPa)	Mean Coefficient of Thermal Expansion (μm/m/°C)			Thermal Conductivity (W/m.K)		Specific Heat 0-100°C (J/kg.K)	Electrical Resistivity (nΩ.m)
			0-100°C	0-315°C	0-538°C	at 100°C	at 500°C
321	8027	193	16.6	17.2	18.6	16.1	22.2	500	720

Grade specifications for 321 grade stainless steel

Grade	UNS No	Old British		Euronorm		Swedish SS	Japanese JIS
		BS	En	No	Name
321	S32100	321S31	58B, 58C	1.4541	X6CrNiTi18-10	2337	SUS 321
321H	S32109	321S51	-	1.4878	X10CrNiTi18-10	-	SUS 321H

Possible alternative grades to 321 grade stainless steel

Grade	Why it might be chosen instead of 321
304L	The requirement is for resistance to intergranular corrosion, not for high temperature strength
3CR12	Only mild "high temperature" environment is present… up to about 600°C.
304H	Only mild "high temperature" environment is present… up to about 800°C.
310	The temperature of the operating environment is up to about 1100°C - too high for 321 or 321H.
S30815 (253MA)	The temperature of the operating environment is up to about 1150°C- too high for 321 or 321H.