| Material family | Austenitic chromium-nickel stainless steel | Combines corrosion resistance, toughness, weldability, and ease of forming. | Commonly supplied in annealed plate and sheet conditions. |
| Typical chemical composition | Cr: 18.0–20.0% Ni: 8.0–10.5% | Chromium supports passive-film formation, while nickel stabilizes the austenitic structure and improves toughness. | Typical ASTM A240 Type 304 composition limits; product specifications should be checked for each order. |
| Carbon content | Maximum 0.07% | Supports corrosion performance and helps maintain the standard 304 grade chemistry. | For more demanding welded corrosion-service conditions, 304L may be selected instead. |
| Tensile strength | Minimum 515 MPa | Provides a practical strength level for fabricated enclosures, tanks, frames, guards, and general process equipment. | Typical minimum requirement for annealed plate under ASTM A240; actual values vary by product and thickness. |
| Yield strength | Minimum 205 MPa | Offers useful resistance to permanent deformation in properly designed structures and fabricated components. | Typical 0.2% offset yield requirement for annealed plate. |
| Elongation | Minimum 40% in 50 mm | High ductility supports bending, deep drawing, rolling, flanging, and other cold-forming operations. | Typical minimum value for annealed plate; test direction and specimen requirements apply. |
| Hardness | Approximately 150–200 HV | Balances ease of cutting and forming with adequate resistance to handling damage and surface wear. | Indicative annealed range; hardness depends on cold work, thickness, heat treatment, and test method. ASTM A240 commonly specifies a maximum of 201 HB for Type 304. |
| Weldability | Excellent | Suitable for TIG, MIG/GMAW, manual metal arc, resistance, and laser welding when procedures are correctly controlled. | Preheating is generally not required. Excessive heat input and interpass temperature should be controlled to limit distortion and sensitization. |
| Post-weld treatment | Usually no post-weld heat treatment | Can reduce fabrication time and simplify field or workshop production. | Pickling, passivation, or mechanical cleaning may be used to restore the surface after welding, depending on service requirements. |
| Formability | High | Supports press braking, roll forming, bending, spinning, and drawing with appropriate tooling. | Work hardening is significant; use suitable tooling, adequate forming force, and generous radii for demanding bends. |
| Bending behavior | Good cold-bending capability | Enables production of channels, covers, brackets, tanks, ducting, panels, and formed profiles. | Minimum inside radius is application-specific and depends on thickness, grain direction, tooling, and bend method. |
| Density | Approximately 8.0 g/cm³ | Provides a predictable basis for weight estimation, shipping calculations, lifting plans, and structural design. | Use project-specific mill data for detailed mass calculations. |
| Thermal conductivity | Approximately 16.2 W/m·K at 100°C | Lower thermal conductivity than carbon steel can help reduce heat spreading but requires attention to welding heat control. | Thermal properties vary with temperature and material condition. |
| Coefficient of thermal expansion | Approximately 17.2 × 10−6/K from 20–100°C | Suitable for many thermal-service applications when expansion, contraction, and weld distortion are included in the design. | Expansion allowances are important in long runs, restrained joints, and dissimilar-metal assemblies. |
| Corrosion resistance | Good in many atmospheric and mildly corrosive environments | Reduces the need for coatings in suitable service conditions and supports long service life with proper maintenance. | Not recommended without specialist review for high-chloride, strongly reducing, or severe chemical environments. |
| Surface and hygiene suitability | Available in smooth, cleanable finishes | Useful for food-processing, architectural, pharmaceutical, commercial kitchen, and hygienic equipment applications. | Finish selection, cleaning practice, weld quality, and passivation affect final performance. |
| Global specification compatibility | Commonly designated as 304, UNS S30400, EN 1.4301, and X5CrNi18-10 | Widely recognized designations simplify international procurement, fabrication documentation, and material substitution reviews. | Equivalent designations are not automatically identical in every standard; verify the applicable specification and certification. |