HASTELLOY® C-22® alloy - Haynes International, Inc.

ISOCORROSION DIAGRAMS*
The isocorrosion diagrams shown
on this page were plotted using
data obtained in laboratory tests in
reagent grade acids. These data
should be used only as a guide.
It is recommended that samples
be tested under actual plant
conditions.
Temperature, °F
200
150
100
Resistance to Nitric Acid
Corrosion rates in parentheses are in mm/year
Boiling Point Curve
5 mpy
(0.13)
20 mpy
(0.51)
0 10 20 30 40 50 60 70
Concentration, Weight Percent
Resistance to Hydrochloric Acid
Corrosion rates in parentheses are in mm/year
Boiling Point Curve
10
50
Temperature, °F
300
250
200
150
100
Resistance to Phosphoric Acid
Corrosion rates in parentheses are in mm/year
Region of corrosion rate instability
Boiling Point Curve
Resistance to Sulfuric Acid
5 mpy
(0.13)
20 mpy
(0.51)
0 10 20 30 40 50 60 70
Concentration, Weight Percent
80
150
100
50
Temperature, °C
100
Corrosion rates in parentheses are in mm/year
Temperature, °F
200
150
200 mpy
(5.1)
50 mpy
(1.3)
20 mpy
(0.51)
75
Temperature, °C
Temperature, °F
250
200
Boiling Point Curve
200 mpy
(5.1)
50 mpy
(1.3)
150
100
Temperature, °C
100
5 mpy
(0.13)
5 mpy
(0.13)
50
150
100
5 mpy
(0.13)
20 mpy
(0.51)
50
0 10 20 30 40
Concentration, Weight Percent
0 10 20 30 40 50 60 70
Concentration, Weight Percent
80
90 100
*All test specimens were heat-treated at 2050°F (1121°C), rapid quenched and in the unwelded condition.
HASTELLOY ® C-22 ® alloy 12