Stainless Steel 304 / 1.4301 – UNS S30400

Grade: X5CrNi18-10
Number: 1.4301
Classification: Austenitic stainless steel
Density: 7.9 g/cm³

Standards

• EN 10088-2: 2005 – Technical delivery conditions for sheet/plate and strip
• EN 10088-3: 2005 – Semi-finished products, bars, rods, wire, sections
• EN 10028-7: 2007 – Flat products for pressure purposes
• EN 10222-5: 2000 – Steel forgings for pressure purposes
• EN 10151: 2003 – Stainless steel strip for springs
• EN 10216-5: 2014 – Seamless steel tubes for pressure purposes
• EN 10217-7: 2005 – Welded steel tubes for pressure purposes
• EN 10296-2: 2005 – Welded circular tubes for engineering
• EN 10253-3/4: 2008 – Butt-welding pipe fittings
• EN 10269: 1999 – Steels/nickel alloys for fasteners
• EN 10272: 2007 – Bars for pressure purposes
• EN 10263-5: 2001 – Cold heading/cold extrusion
• EN 10250-4: 2000 – Die forgings for engineering
• EN 10297-2: 2005 – Seamless circular tubes for mechanical use
• EN 10088-4/5: 2009 – Construction stainless standards

Applications

• Saucepans
• Springs, screws, nuts & bolts
• Sinks & splash backs
• Architectural panelling
• Tubing
• Brewery, food, dairy and pharmaceutical production equipment
• Sanitary ware and troughs

Supplied Forms

• UNS S30400 Sheet
• UNS S30400 Strip
• UNS S30400 Bar
• UNS S30400 Plate
• UNS S30400 Pipe
• UNS S30400 Tube
• UNS S30400 Coil
• UNS S30400 Fittings
• UNS S30400 Steel Butt Weld Pipe Fittings
• UNS S30400 Steel Socket Weld & Threaded Fittings
• UNS S30400 Steel Flanges
• UNS S30400 Steel Fasteners

Available Types

• UNS S30400 Elbows
• UNS S30400 Tees
• UNS S30400 Reducers
• UNS S30400 End Caps
• UNS S30400 Stud Ends
• UNS S30400 Crosses
• UNS S30400 Couplings
• UNS S30400 Plugs
• UNS S30400 Unions
• UNS S30400 Olets
• UNS S30400 Swage Nipples
• UNS S30400 Hex Nipples
• UNS S30400 Hex Bushings
• UNS S30400 Weld Neck Flanges
• UNS S30400 Slip On Flanges
• UNS S30400 Blind Flanges
• UNS S30400 Threaded Flanges
• UNS S30400 Socket Weld Flanges
• UNS S30400 Long Weld Neck Flanges
• UNS S30400 Spectacle Blind Flanges
• UNS S30400 Spade Flanges
• UNS S30400 Spacer Flanges
• UNS S30400 Stud Bolts
• UNS S30400 Hex Bolts
• UNS S30400 Nuts
• UNS S30400 Heavy Hex Nuts
• UNS S30400 Flat Washers

Alloy Designations

Stainless steel grade 1.4301/304 also corresponds to: S30400, 304S15, 304S16, 304S31 and EN58E.

Corrosion Resistance

304 has excellent corrosion resistance in many environments and when in contact with different corrosive media. Pitting and crevice corrosion can occur in environments containing chlorides. Stress corrosion cracking can occur above 60°C.

Heat Resistance

304 has good resistance to oxidation in intermittent service up to 870°C and in continuous service to 925°C. However, continuous use at 425-860°C is not recommended. In this instance 304L is recommended due to its resistance to carbide precipitation. Where high strength is required at temperatures above 500°C and up to 800°C, grade 304H is recommended. This material will retain aqueous corrosion resistance.

Fabrication

Fabrication of all stainless steels should be done only with tools dedicated to stainless steel materials. Tooling and work surfaces must be thoroughly cleaned before use to avoid cross contamination which may discolour the surface of the fabricated product.

Cold Working

304 stainless steel readily work hardens. Fabrication methods involving cold working may require an intermediate annealing stage. A full annealing operation should be performed at the end of fabrication to reduce internal stresses and optimise corrosion resistance.

Hot Working

Hot working such as forging should occur after uniform heating to 1149-1260°C followed by rapid cooling to ensure maximum corrosion resistance.

Machinability

304 has good machinability. Use sharp cutting tools to avoid work hardening, make deep cuts, and apply adequate coolants and lubricants due to its low thermal conductivity.

Heat Treatment

304 stainless steel cannot be hardened by heat treatment. Annealing can be done by heating to 1010-1120°C followed by rapid cooling.

Weldability

Fusion welding performance for type 304 stainless steel is excellent. Use grade 308 stainless steel filler rods or 308L for 304L. Post-weld annealing may be required for heavy sections. Use grade 321 if post-weld heat treatment is not feasible.

Chemical Composition

Mechanical Properties

Physical Properties