Grade Type UNS No.
    Related
    Spec
303 Austenitic S30300
304 Austenitic S30400
304L Austenitic S30403
316 Austenitic S31600
316L Austenitic S31603
316Ti Austenitic S31635
317L Austenitic S31703
310 Austenitic S31000
321 Austenitic S32100
253MA Austenitic S30815
     
904L Austenitic N08904
420C Martensitic S42000
431 Martensitic S43100
17-4 PH Martensitic S17400
(630)    
440C Martensitic S44004
444 Ferritic S44400
3CR12 Ferritic S41003
2101 Duplex S32101
2205 Duplex S31803
2304 Duplex S32304
2507 Duplex S32750

 

GradeTypical Chemical Composition
  
 CMnNiCrMoPSSiOther
303 .15 Max 2.0 Max 8-10 17-19 0.6 Max .20 Max .15 Min 1.0 Max  
304 .08 Max 2.0 Max 8-10.5 18-20   .045 Max .03 Max 1.0 Max  
304L .03 Max 2.0 Max 8-12 18-20   .045 Max .03 Max 1.0 Max  
316 .08 Max 2.0 Max 10-14 16-18 2-3 .045 Max .03 Max 1.0 Max  
316L .03 Max 2.0 Max 10-14 16-18 2-3 .045 Max .03 Max 1.0 Max  
316Ti .08 Max 2.0 Max 10-14 16-18 2-3 .045 Max .03 Max 1.0 Max Ti 0.5
317L .03 Max 2.0 Max 13.0 18-20 3-4 .045 Max .03 Max 1.0 Max  
310 .25 Max 2.0 Max 19-22 24-26   .045 Max 0.3 Max 1.5 Max  
321 .08 Max 2.0 Max 9-12 17-19   .045 Max .03 Max 1.0 Max Ti0.5 Min
253MA .10 Max 0.8 Max 10-12 20-22   0.04 Max .03 Max 2.0 Max N .18
                  Ce .15
904L .02 Max 2.0 Max 23-28 19-23 4-5 .045 Max .03 Max 1.0 Max Cu 1.5
420C .5 Max 1.0 Max   12-14   .04 Max .03 Max 1.0 Max  
431 .2 Max 1.0 Max 1.25-2.5 15-17   .04 Max .03 Max 1.0 Max  
17-4 PH .07 Max 1.0 Max 3-5 15-17.5   .04 Max .03 Max 1.0 Max Cu 4
(630)                 Nb + Ta .3
440C 1.2 Max 1.0 Max 1.0 Max 16-18 0.75 Max .04 Max .03 Max 1.0 Max  
444 .02 Max 1.0 Max 1.0 Max 17.5-19.5 1.7-2.5 .04 Max .03 Max 1.0 Max Ti 0.4
3CR12 .03 Max 1.5 Max 1.5 Max 10.5-12.5   .04 Max .03 Max 1.0 Max Ti 4(C+N)
2101 .04 Max 6.0 Max 1.35-1.7 21-22 0.1-0.8 .04 Max .03 Max 1.0 Max N 0.2 Cu0.45
2205 .03 Max 2.0 Max 4.5-6.5 21-23 2.5-3.5 .03 Max .02 Max 1.0 Max N 0.15
2304 .03 Max .03 3-5.5 21.5-24.5 .05-.6 .03 Max .02 Max 1.0 Max N 0.1
2507 .03 Max 1.2 Max 6-8 24-26 3-5 .035 Max .02 Max .08 Max N 0.3

 

GradeTypical Mecha-Properties
% Min
Condition
 YieldnicalHardnessTensile  
 StrengthUTS Elongation 
 MPaMPaBHNRb<1.2>1.2 
 MinMinMaxMaxmmmm 
303 240 585 160 84 50 50 Annealed
304 205 520 202 92 40 40 Annealed
304L 170 485 183 88 40 40 Annealed
316 205 520 219 95 40 40 Annealed
316L 170 485 217 95 40 40 Annealed
316Ti 205 520 217 95 40 40 Annealed
317L 205 515 217 95 40 40 Annealed
310 205 520 170 85 40 40 Annealed
321 205 520 217 95 40 40 Annealed
253MA 310 600 - - 40 40 Annealed
904L - - - - 40 40 Annealed
420C - S20 192 92   12 Hardenable
431   965 Max 262 10 - - Hardenable
17-4 PH 1000 1070 331 - 12 12 Solution Hardened
(630)              
440C - - 223 97 - - Hardenable
444 310 415 200 95 20 20 Annealed
3CR12 340 460 - 160 40 40 Annealed
2205 450 620 290 32RC 25 25 Annealed
2304 400 600 290 31RB 25 25 Annealed

 

Grade Common Applications
303 Free machining steel used where extensive machining is required. Corrosion resistance and weldability inferior to 302.
304 General purpose steel with good corrosion resistance for most applications. Used for architecture, food processing, domestic sinks and tubs and deep drawing applications.
304L Chemical plant and food processing equipment, where freedom from senitisation is required in plate.
316 Most commonly used s/s main applications ie. marine, chemical, food, mining.
316L A low carbon modification of 316 where heavy section weldments are required without the risk of intergranular corrosion.
316Ti A titanium stabilised version of 316. Excellent high temperature strength.
317L For chemical plant. Has greater corrosion resistance than 316L notably with brines and halogen salts.
310 Furnace parts and equipment. Resistant to temperatures 900ºC to 1100ºC.
321 Heavy weldments in chemical and other industries. Suitable for heat resisting applications to 800ºC. Not suitable for bright polishing.
253MA Furnace parts and equipment. Resistant to temperatures up to 1150ºC.
904L High resistance to: general corrosion in e.g. sulphuric and actic acids; crevice corrosion; stress corrosion cracking; pitting in chloride bearing solutions. Good weldabilty.
420C Developed for high hardness after heat treatment. Used for cutting tools, surgical knives, etc.
431 Used for pump shafts etc. Similar corrosion resistance to T302.
17-4 PH (630) Main applications: pump shafts, marine boat shafts, valve stems. Similar corrosion resistance to type 304.
440C Capable of being hardened to 60 Rc. Highest hardness and abrasion resistance of all the stainless steels. Corrosion resistance similar to 410.
444 Heat exchanger and hot water tanks, and in chloride containing waters. Not prone to chloride stress corrosion - superior resistance to pitting, crevice and intergranular corrosion. Possesses excellent deep drawing properties.
3CR12 Excellent wet abrasion resistance. Used in hoppers, bins, tanks etc.
2205 Superior corrosion resistance to 316L and 317L, combined with high strength. Excellent stress corrosion and abrasion resistance. Typically used in heat exchangers, gas scrubbers, fans, chemical tanks, flowlines, marine and refinery applications.
2304 Similar corrosion resistance to 316L. Higher yield strength, corrosion and stress-corrosion crackling resistance is required in marine, mining, chemical, food and power industries. Particularly useful in nitric acid.