Alloy 20

Alloy 20 is a nickel-iron-chromium austenitic alloy that was developed for maximum resistance to acid attack, specifically sulfuric acid. This superalloy has excellent resistance to general corrosion, pitting, and crevice corrosion in chemicals containing chlorides and sulfuric, phosphoric, and nitric acids. It also contains niobium for stabilization against sensitization and resultant intergranular corrosion. Alloy 20 combines excellent corrosion resistance with elevated mechanical properties and relatively easy fabrication.

Chemical Composition

	Alloy 20
Ni	32 – 38
Fe	Bal
Cr	19 – 21
Cu	3 – 4
Mo	2 – 3
Nb	0.1 – 0.3
C	0.02 max
Mn	1 – 2
P	0.02 max
S	0.005 max
Si	0.7 max

Specifications

Standard	Alloy 20
UNS	N08020
Werkstoff Nr.	2.4660

Mechanical & Physical Properties – Alloy 20

Density	8.1 g/cm3
Melting Point	1443 °C (2430 °F)
Tensile Strength	Psi – 80000 , MPa – 551
Yield Strength (0.2%Offset)	Psi – 35000 , MPa – 241
Elongation	30 %