STAINLESS STEEL CHEMICAL COMPOSITION
S.S.
200
202
301
302
302B
303
303Se
304
304L
305
308
309
309s
310
310s
314
316
316L
317
321
347
 Carbon
0.12
0.12
0.15
0.15
0.15
0.15
0.15
0.08
0.03
0.12
0.08
0.20
0.08
0.25
0.08
0.25
0.08
0.03
0.08
0.08
0.08
 Manganese
7.5/10
5.5/7.5
2.00
2.00
2.00
2.00
2.002.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
2.00
 Silicone
0.9
0.9
1.00
1.00
2.0/3.0
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.5
1.5
1.5/3.0
1.00
1.00
1.00
1.00
1.00
 Chromium
14/16
16/18
16/18
17/19
17/19
17/19
17/19
18/20
18/02
17/19
19/21
22/24
22/24
24/26
24/26
24/26
23/26
16/18
18/20
17/19
17/19
 Nickel
0.5/2.0
0.5/4.0
6.0/8.0
8.0/10
8.0/10
8.0/10
8.0/10
8.0/12
8.0/12
10/13
10/12
12/15
12/15
19/22
19/22
19/22
10/14
10/14
11/15
9.0/12
9/13
 Molybdenum
0.2
0.2
                            
2.0/3.0
2.0/3.0
3.0/4.0
    
 Phosphorus
0.06
0.06
0.045
0.045
0.045
0.20
0.20
0.045
0.045
0.045
0.045
0.045
0.045
0.045
0.045
0.045
0.045
0.045
0.045
0.045
0.045
 Nitrogen
0.25
0.25
                                      
 Suiphur    
0.03
0.03
0.03
0.15MIN
-
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
0.03
 Selenium            
0.15MIN
                            
 Aluminium                                          
 Titanium                                      
5XC
  
 Cb+Ta                                        
10XC
 Tensile
 Strength 		105 105
110
90
95
90
90
85
60
85
85
90
90
95
95
100
85
78
90
87
92
 2% Yield
 Strength 		55 55
40
37
40
35
35
35
30
37
35
40
40
40
40
50
35
30
40
35
35
 Elongation
 in 2' 		55 55
60
55
50
50
50
55
55
55
55
45
45
45
45
45
55
55
50
55
50
 Rockwell 90 90
85
82
85
84
84
80
76
82
80
85
85
87
87
87
80
76
85
80
84
 Brinell 185 185
165
155
165
160
160
150
140
156
150
165
165
170
170
170
150
145
160
150
160
                                           
       
En58M
  
En58E
150-801C
                  
En58J&H
    
En58C
  
     
X12
CrNi17.7
X2
CrNi18.8
     
X5
CrNi18.9
X5
CrNi18.8
X12
CrNi18.8
           
x5
CrNiMo18.12
X2
CrNiMo19.1
X10
CrNiMo18.9
   
 
AUST.
  
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
AUST.
CHEMICAL COMPOSITION OF AISI WROUGHT STAINLESS STEELS
Physical corrosion resistance & other properties of important S.S.Grades
 S.S.Grade
201
202
301
302
304
304L
309
309S
310
310S
316
316L
321
347
409
430
434
410
 Density
7.9
7.9
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
8.0
7.7
7.8
7.8
7.8
 Sp.Elec. Resist 20C micro
72
72
72
72
72
72
78
78
78
78
74
74
72
73
60
60
60
57
 Sp. Heat (0-100c)
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
0.5
46
46
46
46
 Ther. Conductivity
16.3
16.3
16.3
16.3
16.3
16.3
14.2
14.2
14.2
14.2
16.3
16.3
16.3
16.3
25.1
26.0
26.0
25.1
 
15.7
18.4
17.0
17.2
17.3
17.3
15.0
15.0
15.9
15.9
15.9
15.9
16.6
16.6
11.7
10.4
11.9
9.9
 Mild water
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
 Industrial
X
X
X
X
X
X
X
X
X
X
X
X
X
X
  
X
X
  
 Marine
X
X
X
X
X
X
X
X
X
X
X
X
X
X
    
X
  
 Salt Water
                 
X
X
              
 Mild
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
 Oxidising
X
X
X
X
X
X
X
X
X
X
X
X
X
X
  
X
X
  
 Reducing
                    
X
X
            
 Abrasion Resistance
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
Good
 Cold Forming
Fair
Good
Good
Excel
Excel
Good
Good
Good
Good
Good
Good
Good
Good
Good
Fair
Fair
Fair
Fair
 Weldability
Good
Good
Excel
Excel
Excel
Excel
Good
Excel
Good
Excel
Excel
Excel
Excel
Excel
Fair
Fair
Fair
Fair
 Melting Flange
1400 1420
1400 1450
1370 1400
1400 1430
1430 1510
1480 1530
 Scaling Temp
800
800
800
900
900
900
1100
1100
1100
1100
900
900
900
900
700
800
800
700

 


Mechanical Properties
200 Series 300 Series
0.2% proof stress (kg/mm2)
35.5 26.7
Tensile Strength (kg/mm2) 77.2 59
Elongation 50.0 55.6
GSN 8-9 7.8
Hv 208 157
Erchsen value 12.5 12.9
Limited Drawing Limit 2.0 2.3 to 2.5

Corrosion Properties

Considering that the components manufactured out of these sheets are used in normal atmospheric conditions chromium level 14.5% to 15.5% is quiet to resist pitting corrosion.

Experiments carried out showed the following result

  • Kitchen utensils and cutleries retained their surface finish and luster similar to 304 Grade
  • Laboratories scaled experiments carried out under different media revealed the following data:

Corrosion Rates of the Stainless Steels Fully Immersed in
3% Sodium Chloride

Stainless
Steel
Temperature Duration Corrosion
Rate 		Visual Observation
°K °C (Hour) x 10^-2
mmpy
J 303±2 30±2 720 2.58 Localised
Attack
S 303±2 30±2 720 3.29 Localised
Attack
J 371±2 98±2 100 0.25 Material Remained Same
S 371±2 98±2 100 0.43 Material Remained Same

Corrosion Rates of the Stainless Steels Fully Immersed in Organic Acid Mixture (0.5% Citric Acid+0.5% Tartaric Acid)

Stainless
Steel
Temperature Duration Corrosion
Rate  		 Visual Observation  
°K °C (Hour) x10^-2
mmpy
J 303±2 30±2 720 0.44 Fungal growth
S 303±2 30±2 720 0.38 Fungal growth
J 371±2 98±2 100 0.34 Material Remained Same
S 371±2 98±2 100 0.17 Material Remained Same

Dissolution Behaviour of the three stainless steels in 3% NaCl on total Immersion

SS Temp
°C 		Duration
(hours) 		Elements estimated by AAS (ppm)
Fe Cr Cu Mn Ni Ti      
J 30±2 720 0.177 0.011 0.003 0.508 - -
S 30±2 720 0.157 0.048 0.024 0.048 - -
J 98±2 100 0.057 0.007 0.015 0.829 - -
S 98±2 100 0.010 0.012 0.028 0.035 - -

The above data suggest that the corrosion resistant as good as 304 Grade SS under normal atmospheric conditions

Formability

The blanks cut from the annealed sheets respond favorably to the commonly fabrication operations such as deep drawing ,spinning, welding ,bidding ,rib formation, embossing, electro deposition of metals like Copper and necking of cylindrical parts.

The quantified data on formability is given below: Limited Drawing Ration - 2
Percentage Stretch in Spinning - 30%
Erichsen Value - 12.5