Materials

AISI 3211.4541/1.4878 – UNS S32100 – X6CrNiTi 18 10

Type 321 is a stabilized austenitic stainless steel similar to Type 304 but with a titanium addition of at least five times the carbon content. This titanium addition reduces or prevents carbide precipitation during welding and in 800 – 1500F(427 – 816C) service. It also improves the elevated temperature properties ofthe alloy. Type 321 provides excellent resistance to oxidation and corrosion and possesses good creep strength. It is used primarily in applications involving continuous and intermittent service temperatures within the carbide precipitation range of 800 – 1500F (427 – 816C). Applications include annealing covers, high-temperature tempering equipment, diesel and heavy duty automotive exhaust systems, firewalls, stack liners,boiler casings, welded pressure vessels, jet aircraft components, radiant super-heaters, bellows and oil refinery equipment.

Products

AISI 321
Availability
seamless-pipe Seamless Tubes

 stock
welded-pipe Welded Tubes
plate Plates  stock
bar Bars  stock
flanges Flanges  stock
accessories Fittings  stock

Applications

  • Thermal oxidizers
  • Aircraft piston engine manifolds
  • Expansion joints
  • Refinery equipment
  • High temperature chemical process equipment

General characteristics

  • Immune to intergranular corrosion when heated within the carbide precipitation range.
  • Titanium addition eliminates the formation of chromium carbides at the grain boundaries by tying up the carbon
  • and nitrogen as titanium carbides or nitrides
  • Better high temperature properties than 304 or 304L
  • Excellent weldability in field

Technical information

Specifications

 

321 – UNS S32100
Products Norm ASTM
Seamless Tubes A-213 A-312
Welded Tubes A-249 A-312
Plates A-240
Bars A-276 A-479
Flanges A-182
Fittings A-403

Chemical specifications %

 

321 – UNS S32100
Element Simbol Maximum
Carbon C 0,08
Manganese Mn 2,00
Phosphorus P 0,045
Sulfur S 0,030
Silicon Si 1,00
Nickel Ni 9,0-12,0
Chrome Cr 17,0-19,0
Nitrogen N 0,00
Titanium Ti >5x(C+N)
Otros

Mechanical Properties

321 – UNS S32100
Norm Rm min. Rp 0,2% min. E4d min.% Z min.% T.I.(J) HR B HB
A-182 75 (515) 30 (205) 30 50
A-213 75 (515) 30 (205) 35 90 192 HBW 100 HV
A-240 75 (515) 30 (205) 40 95 217
A-249 75 (515) 30 (205) 35 90
A-276 75 (515) 30 (205) 30 40
A-312( 75 (515) 30 (205)
A-312(>3/8 inch.) 70 (485) 25 (170)
A-403 75 (515) 30 (205)
A-479 75 (515) 30 (205) 30 40