Alloy 20

Alloy 20 is one of the so-called "super" stainless steels that was designed for maximum resistance to acid attack. It's nickel, chromium, molybdenum and copper content contribute to its overall resistance to chloride-ion stress corrosion cracking and general pitting attack.

Technical Specification Alloy 20
Nominal Composition

Cr: 19.0 - 21

Ni: 32.0 - 38.0

Mo: 2.0 - 3.0

Cu: 3.0 - 4.0

Density

0.27 lb./in3

Modulus of Elasticity (E)

26 x 106 psi

Modulus of Rigidity (G)

10675 ksi

Coefficient of Expansion

8.16 µin/in.-°F (70°F)

Electrical Resistivity

65 ohm -cir mil/ft.

Thermal Conductivity

7.05 Btu/(hr/ft2/in/°F)

Min Size

0.018 in (0.47 mm)

Max Temp

537oC (1000oF)

Uses

Superior resistance to stress corrosion cracking in boiling 20 – 40% sulphuric acid