what is sa 240 gr 304 material steel surface？

Overview of SA 240 GR 304 Material Steel Surface

The SA 240 GR 304 material steel surface refers to the finish or texture applied to the stainless steel plate, sheet, or strip, which affects its appearance, corrosion resistance, and suitability for specific applications. The ASME SA 240 specification focuses on the material's chemical and mechanical properties but does not mandate a particular surface finish; instead, finishes are specified per ASTM A480/A480M or customer requirements.

Common surface finishes for SA 240 GR 304 include 2B (smooth, cold-rolled), No.1 (hot-rolled, rough), and No.4 (brushed), each providing different aesthetics and functional benefits. SA 240 GR 304's surface is naturally corrosion-resistant due to its chromium content, forming a passive oxide layer that protects against rust in mild environments.

Gangsteel’s sa 240 gr 304 plates are available in various finishes like 2B, No.1, No.4, No.8 (mirror), brushed, checkered, embossed, hairline, sand blast, and etched.

Common Surface Finishes for SA 240 GR 304 Material

Surface finishes for SA 240 GR 304 are classified under ASTM A480, with options tailored for aesthetics, hygiene, or durability:

• No.1 and 2B: Standard mill finishes for industrial use, with 2B being smoother and more common for SA 240 GR 304.
• Polished Finishes (No.4, No.8): Enhance aesthetics and cleanability, ideal for food-grade applications.
• Custom Finishes: Gangsteel offers sand blasting, etching, and embossing for specific needs.

The surface of SA 240 GR 304 material is naturally silver-gray with a passive oxide layer that self-heals, providing corrosion resistance without additional coatings. For detailed specs, refer to our SS 304 data sheet.

Chemical Composition of SA 240 GR 304 Material

The chemical composition contributes to the surface's corrosion-resistant oxide layer:

• Chromium: Key to the passive oxide layer, ensuring the surface resists rust in mild environments.
• Nickel: Supports ductility and non-magnetic properties.

Mechanical Properties

The mechanical properties of SA 240 GR 304 for annealed plates (8-75 mm thick) support its use across various surface finishes:

Surface finishes like No.4 or No.8 do not affect bulk mechanical properties but can influence surface hardness slightly.

Physical Properties

• Density: 8.00 g/cm³, ideal for lightweight designs (e.g., a 1m x 1m x 3mm plate weighs ~24 kg).
• Melting Point: ~1400-1450°C.
• Thermal Conductivity: 16.2 W/m·K.
• Coefficient of Thermal Expansion: 17.2 × 10⁻⁶/K.

The surface oxide layer enhances corrosion resistance without altering physical properties.

Corrosion Resistance and Weldability

SA 240 GR 304 offers excellent corrosion resistance on its surface in:

• Atmospheric conditions, freshwater, and mild acids (food-grade applications).
• General environments, outperforming SS204 vs SS 304 due to higher nickel content.

The passive oxide layer self-heals, but finishes like 2B or No.4 can affect cleanability. Weldability is good with ER308 fillers, though SA 240 GR 304L is preferred for critical welds. For chloride-heavy environments, explore sa 240 gr 316l.

Applications of SA 240 GR 304 Material

SA 240 GR 304 material is used in:

• Food Processing: Tanks and equipment with 2B or No.4 surface for hygiene.
• Chemical Industry: Vessels and SA 240 GR 304 pipe with No.1 surface for rough use.
• Architecture: Decorative panels like plat stainless 304 with No.8 mirror surface.
• Automotive: Components with brushed or hairline surface for aesthetics.

For harsher environments, consider sa 240 gr 317l or sa 240 gr 321 for high-temperature stability.

Pricing and Availability at Gangsteel

As of October 15, 2025, SA 240 GR 304 plate prices for 2B surface (3-6mm thick) range from $1.55-$3.50/kg globally, influenced by nickel prices (~$15,325/t). Gangsteel offers competitive pricing starting at $1.60/kg FOB (MOQ 1 ton) for standard sizes (e.g., 4’x8’, 5’x10’) and custom cuts like plate 2 mm SUS 304, with various surface finishes like 2B, No.1, and No.4. Our SS 304 plate price is 5-10% below market averages, and dual-certified SA 240 TP 304/304L plates are available for flexibility. For pricing details, contact admin@gangsteel.com.

Why Choose Gangsteel?

Gangsteel provides certified SA 240 GR 304 plates with customizable surface finishes and competitive SA 240 304 plate price. Our 600+ ton inventory supports global delivery for applications from plat stainless 304 to heavy plates. For quotes or to learn more about SA 240 GR 304 material steel surface, visit our astm a 240 stainless plate page or email admin@gangsteel.com.